Caterpillar GP40 Lift Trucks Service Manuals - PDF DOWNLOAD

®

Lift Trucks

Service Manual Engine 4G15 4G63 4G64 6G72

For use with GP15-35, GP15K-35K, GP40, GPL40, GC15-30, GC15K-30K, GC35K-70K Lift Trucks

99719-34130

INTRODUCTION LP-gas lift trucks are superior to gasoline lift trucks in many ways including cleaner emissions and higher fuel efficiency.

LP-gas is, however, more dangerous than gasoline when handled improperly.

This Shop Manual contains operating instructions and maintenance procedures for the LP-gas ® device of Caterpillar gasoline/LP-gas lift trucks. To ensure safety and maximize the superb features of your lift truck, read this manual thoroughly.

The following mark and designation are used in this manual to call your attention to important instructions and cautions.

< Warning Indication >

Caution

Indicates items that users must always observe in orderto prevent injuries and damage to the vehicle and surrounding area.

Note

Supplementary explanation

99719-34130

STRUCTURE AND FUNCTION Gasoline/LP-gas converter 1 Converter (vaporizer) 2 LP-gas solenoid valve A LP-gas from filter B LP-gas to carburetor C Hot water from engine D Hot water to engine

2

A

1

D B

C 205402

1 2 À 3 4 5 À 6 7 8 9 10 À 11 12 13 À 14 À 15 16 17

Screw Secondary cover Secondary diaphragm Screw Secondary seat lever Secondary seat Secondary pin Fulcrum pin Spring Converter body Primary valve seat Gasket Cover plate Spring Primary valve pin Primary diaphragm Primary cover Screw

À COMPONENTS INCLUDED IN THE REPAIR KIT.

1 2 3À 4 5 6À 7 8 9 10

Parts indicated with an asterisk (À) are included in the repair kit.

11À 12 13 14À 15À 16 17

205132

11

STRUCTURE AND FUNCTION Carburetor 1 Air horn À 2 Air valve À 3 Air valve sealing 4 Air valve spring À 5 Check valve plate À 6 Gasket 7 Adapter À 8 Screw À

1

2À

Components included in the Repair Kit. 3À

4

5À

6À

7 8À 205131A

4.5 Solenoid valves (electromagnetic valves) Solenoid valves are installed in the LP-gas and gasoline lines. These solenoid valves open and close the passages of fuel lines. They are operated by the selector switch. The valve opens when an electric current is supplied.

When an electric current flows to the coil in the solenoid valve, the generated electromagnetic force pushes up the plunger valve located inside the coil against the force of the return spring, opening the passage for the fuel to flow. When there is no electric current supplied, the force of the return spring pushes the plunger and presses it against the seat, thus closing the fuel passage.

The operating electric power is supplied from the starter switch for linked operation.

2 3

1

4

A 1 Return spring 2 Coil 3 Plunger valve

12

201287

4 Cylinder flange A Use bolt for grounding cord connection

OPERATING INSTRUCTIONS FOR GASOLINE/LP-GAS LIFT TRUCKS 1. Starting engine on LP-gas (1) Inspection before starting engine on LP-gas (pre-operation inspection) (a) Make sure that the charge valve on the LP-gas tank is closed. (b) Check the level gauge to make sure that the tank contains LP-gas. Open the gas outlet valve (red).

Inspect the tank mounting bolts and bands for tightness. (c) Check the joints in the LP-gas line (between LP-gas tank and converter) for gas leaks by using a gas detector or soapy solution.

Note: The LP-gas line located between the converter and LP-gas carburetor is checked after the engine starts operating. (d) Check the joints in hot-water hoses for water leaks. (e) Inspect wires for damaged sheaths.

CLOSE

206702

– CAUTION Check wires carefully for possible spark generation. (f) Conduct other pre-operation inspection steps specified for standard vehicles.

(2) Starting engine on LP-gas in extremely cold weather (when engine does not start on LPgas) Note: If it is difficult to start the engine on LP-gas due to low temperatures, use gasoline to start the engine. After the engine reaches a normal operating temperature, switch to LP-gas. (a) Set the gasoline/LPG selector switch to the [GASOLINE] position. (b) Pull the choke button. (c) Turn the starter switch to the [START] position to start the engine. (d) Let the engine operate for about five minutes to warm up. When the engine operation stabilizes, press the choke button to the original position. (e) Set the gasoline/LPG selector switch to [OFF], and wait until the engine stops by itself (thus using the gasoline in the float chamber of the gasoline carburetor).

206703

13

OPERATING INSTRUCTIONS FOR GASOLINE/LP-GAS LIFT TRUCKS (f) Set the gasoline/LPG selector switch to the [LPG] position.

206704

(g) Check to make sure that the choke button is pressed all the way. (h) Press the accelerator to a half-throttle position.

Note: Pumping the accelerator pedal or pressing it to full-throttle position does not feed LP-gas to the engine. (i) Turn the starter switch to the [START] position to start the engine.

1/2

201314

(3) Starting the engine on LP-gas in ordinary temperature Start the engine by following the steps from (f) to (i).

Note: Operating the vehicle when the cooling water temperature is low can cause detonation in the exhaust pipe, failure to rev up or stalling of the engine. Low cooling temperature also causes a shortage of heat supply in the converter for proper vaporization of LP-gas, and this results in freezing of LP-gas. To prevent these problems, be sure to conduct a warm-up operation.

201316

14

OPERATING INSTRUCTIONS FOR GASOLINE/LP-GAS LIFT TRUCKS 2. Stopping engine operating on LP-gas (a) With the engine running, close the gas outlet valve (red) on the LP-gas tank to use all LP-gas in the line.

CLOSE

206702

(b) When the engine stops after using all LP-gas in the line, set the gasoline/LPG selector switch to the [OFF] position.

(c) Turn the starter switch to the [OFF] position.

– CAUTION After operation, remove the key and store in a designated place.

3. Starting engine on gasoline Except the steps described below, the starting procedure is the same as that for standard vehicles. (a) Set the gasoline/LPG selector switch to the [GASOLINE] position. (b) Pull the choke button. (c) Turn the starter switch to the [START] position to start the engine.

206703

15

OPERATING INSTRUCTIONS FOR GASOLINE/LP-GAS LIFT TRUCKS 6.

Caution for using lift truck in extremely cold weather (1) General caution items (a) Make sure that the battery is properly charged. (Specific gravity: 1.26 or higher) (b) Use coolant in the engine cooling water, and make sure that the freezing point of the cooling water is -20°C [-4°F] or lower. (c) Use engine oil with lower viscosity than specified. (Oil viscosity becomes higher during use.)

4. Switching fuel source 4.1 Switching from [LP-gas] to [gasoline] (1) Close the gas outlet valve (red) on the LPgas tank.

(2) After the engine stops by itself, set the gasoline/LPG selector switch to the [GASOLINE] position.

Note: If fuel has not reached the float chamber in the gasoline carburetor during the above step, it is necessary to continue cranking the engine.

4.2 Switching from [gasoline] to [LP-gas] (1) Set the gasoline/LPG selector switch to the [OFF] position, and wait until the engine stops by itself.

(2) Action to take in the event of converter freezing If the converter freezes and becomes covered with white frost, the LP-gas mixture becomes too rich and causes the engine to stall. When this happens, start the engine on gasoline. After the engine warms up sufficiently, switch to [LP-gas].

An attempt to start the engine with a frozen converter or operating the vehicle when the cooling water temperature is low can cause freezing of the converter’s internal parts and result in damage.

If the converter freezes or the converter temperature drops suddenly after the fuel is switched to [LP-gas], inspect the hot water circuit.

Note: If the float chamber of the gasoline carburetor still contains gasoline when the engine is started on LP-gas, excessive fuel (gasoline and LP-gas mixture) enters the engine, making it difficult to start the engine.

(2) Open the gas outlet valve (red) on the LPgas tank.

(3) Set the gasoline/LPG selector switch to the LPG position, and restart the engine.

5. Parking and storing (1) If the vehicle is not operated for an extended period of time, close the gas outlet valve on the LP-gas tank.

(2) Before stopping the engine to park or store, close the gas outlet valve on the LP-gas tank while the engine is running to use all gas in the line.

– CAUTION If the vehicle is not operated for an extended period of time, cover the LPgas tank to protect it from direct sunlight, and ensure that the surface temperature of the tank does not exceed 40°C [104°F].

16

OPERATING INSTRUCTIONS FOR GASOLINE/LP-GAS LIFT TRUCKS 7. Relocating tank bracket (1) Pull the stopper forward to disengage it from the tank bracket.

(2) Tilt the tank bracket all the way back.

– CAUTION ←

Be careful not to allow the tank bracket to contact people or objects in the surrounding area when relocating.

STOPPER

206776

8. Charging LP-gas (1) Move the vehicle to the specified location, stop the engine and follow the instructions of the operator of the LP-gas supply equipment.

(2) Do not request the operator to charge more than the specified amount.

(3) Do not use any flame in the LP-gas refill area.

9. Exchanging LP-gas tank

– CAUTION

← BAND

The tank must be exchanged in a wellventilated area. Make sure there is no flame in the area.

(1) Close the gas outlet valve on the LP-gas tank.

(2) Disconnect the LP-gas hose from the gas outlet valve.

(3) Remove the clamps and the bands that secure the LP-gas tank in place. Then, dismount the LP-gas tank.

17

CLAMP

→ 206777

ACTIONS TO BE TAKEN IN THE EVENT OF A FAILURE (1) When you smell the gas or notice something wrong with the LP-gas equipment during operation, immediately stop the lift truck in a safe area, turn the starter switch to “OFF” position, close the service valve (RED) of LP-gas tank, and try to find the cause. (It is advisable to have a test kit on hand for detecting gas leakage in the event of the failure.)

(2) If the internal pressure of LP-gas tank rises too high for one reason or another to cause the safety valve to open and let out the excess pressure, sprinkle water over the tank and, at the same time, extinguish the fire burning near the lift truck, if any, and ventilate the working area to rarefy the leakage gas.

(3) When gas leakage is evident, extinguish the fire burning near by and close the service valve (RED) of the tank as soon as possible, then take a split-second action.

(4) If there is a possibility of fire in the event of collision or overturning of the lift truck, close the service valve (RED) of the tank as soon as possible.

(5) The LP-gas tank installed in correct position will not explode even if it is in a blaze.

What to do in the event of emergency is to remove inflammable material from around the tank quickly.

(6) Use a dry-chemical (powder) type or carbon dioxide type extinguisher. Never use water. It is a good practice, however to sprinkle a large quantity of water over the LP-gas tank for cooling it down while extinguishing the fire.

(7) Only trained and authorized personnel should fill or exchange LP-gas tanks.

(8) Personnel engaged in filling of LP-gas tanks should wear protective clothing such as a face shield, long sleeves and gauntlet gloves.

(9) Do not refuel or store LP-gas powered lift trucks near any underground entrances, elevator shafts, or any other place where LP-gas could collect in a pocket causing a potentially dangerous condition.

(10) Do not leave the lift truck, for even a short period of time, in the vicinity of objects with high temperatures, such as ovens and furnaces. The heat may raise the pressure of the fuel and open the relief valve.

(11) Close the service valve on the tank when LP-gas fueled lift trucks are parked overnight or stored for a long period of time indoors with the fuel tank in place.

(12) Close the valves on empty tanks.

(13) Examine all LP-gas tanks before filling again before reuse, for damage to the valves, liquid gauge, fitting and hand wheels.

(14) Check for dents, scrapes or other damage to the pressure vessel and for dirt or debris in the openings.

(15) All defective or damaged LP-gas tanks must be removed from service.

(16) The careless handling of LP-gas tanks can result in a serious accident. Extreme care should be exercised when transporting tanks so that the tanks are not damaged.

(17) The storage and handling of liquid fuels in the U.S.A., should be in accordance with the NFPA No.30, “Flammable and Combustion Code.” Outside the U.S.A. store and handle in accordance with local regulations.

(18) The lift truck should be refueled only at designated safe locations. Safe outdoor locations are preferable to those indoors.

18

ACTIONS TO BE TAKEN IN THE EVENT OF A FAILURE (19) DO not completely fill the tank. The fuel expands when it gets warm and it may overflow. This will create a fire hazard.

(20) Only trained and authorized personnel should fill or exchange LP-gas tanks.

(21) Do not drop, throw, roll or drag LP-gas tanks. Do not strike LP-gas tanks or any associated parts of the tanks or fuel systems.

(22) Check the LP-gas tank for secure mounting. Loose tanks can cause pressure fuel lines to leak, resulting in personal injury.

(23) Carefully read the caution labels.

“MAINTENANCE” DECAL

‘DUAL FUEL SYSTEM” DECAL “L.P.G.” DECAL

“FUEL” DECAL

“KNOB INST” DECAL

“DUAL FUEL INST” DECAL 207419

19

TROUBLESHOOTING Engine does not start even though there is no equipment abnormality.

Difficulty in starting or failure to start

Repeated attempts to start engine with LP-gas or gasoline fed too much fuel to engine.

No LP-gas in tank

Refill LP-gas tank.

Be sure to open gas outlet valve on LP-gas tank.

Improper operating procedure

Do no use choke.

Do not press accelerator pedal all the way.

Rich fuel mixture

Wait for a while and try again. If gasoline remains in float chamber of gasoline carburetor, start engine using gasoline, then switch to LP-gas.

Malfunction of LP-gas solenoid valve

Check to see that solenoid valve produces an operating sound when a wire is connected between positive (+) terminal (red lead wire) of LP-gas solenoid and positive (+) terminal of battery.

If no operating sound is produced, inspect wiring. If no abnormality is found in wiring, replace solenoid valve.

Overactivation of excess flow valve in gas outlet valve on LPgas tank

Close gas outlet valve (red handle) on LP-gas tank, and leave in that condition for about 1 minute. When gas pressure stabilizes and valve deactivates, open gas outlet valve.

Clogged filter

Disassemble and clean filter.

No LP-gas is supplied to converter.

Replace filter and screen.

Engine starts immediately.

but

Improper idle speed adjustment

Adjust idle fuel mixture adjustment screw on LP-gas carburetor.

Excessively low cooling water temperature

Use coolant (start engine using gasoline).

Check for clogs in cooling water hoses and thermostat damage.

Faulty gasoline solenoid valve feeding gasoline and LP-gas at the same time

Check for dust adhesion on valve seat in gasoline solenoid valve, and clean it, if necessary.

If cleaning does not solve the problem, replace.

Insufficient gas pressure due to low temperature

If LP-gas tank pressure is lower than 98 kPa (1 kgf/cm2) [14.2 psi], increase propane content of LPgas. (Ambient temperature: 0°C [32°F])

Malfunction of LP-gas carburetor

Check for sticking of air valve.

stalls

Others

If air valve sealing ring is worn, replace.

Mixing of air due to faulty connection of air hose to LP-gas carburetor

20

Use hose clamp to tighten the connection.

TROUBLESHOOTING Improper setting of idle fuel mixture adjustment screw on LP-gas carburetor

Make adjustment.

Accumulation of rubber particles, oil and metal particles inside converter

Disassemble and clean.

Torn diaphragm in converter

Replace diaphragm.

Faulty secondary valve seat in converter

If valve does not completely rest on seat, replace seat.

Primary pressure exceeding 14.7 kPa (0.15 kgf/cm2) [2.1 psi] and, causing rich fuel mixture. (Damaged primary valve seat)

Replace primary valve seat.

Engine power decreases gradually during operation, and engine speed does not increase.

No LP-gas

Refill with LP-gas. Exchange LP-gas tank.

Engine vibrates and emits thick exhaust smoke.

Faulty gasoline solenoid valve feeding gasoline and LP-gas at the same time

Check for dust adhesion on valve seat in gasoline solenoid valve, and clean it, if necessary.

If cleaning does not solve the problem, replace.

Freezing of converter Hot water (engine cooling water) temperature is too low, or insufficient LP-gas

Remove hot-water hose at outlet to check if hot water is properly circulating (clogged hose).

Start engine with gasoline, then switch to LP-gas when indicator of water temperature gauge moves to white zone.

Gas leaks from damaged LP-gas hose

Repair damaged hose.

Torn primary diaphragm in converter

Stop operation immediately, and replace primary diaphragm.

Broken wire

Inspect electrical wires and grounding wires.

Damaged solenoid valve coil

Replace solenoid valve.

Accumulation of solenoid valve

Clean. After cleaning, shake solenoid valve and listen for the sound of moving valve unit.

Faulty idling operation

Engine operation stops or is unstable at idle speed, or idle speed is too high.

Poor engine performance or stalling of engine

Others

Engine stalls a short time after startup.

Strong gas smell

Solenoid valve does not produce operating sound when switch is turned ON.

dust

21

inside

Poor acceleration

TROUBLESHOOTING Damaged primary valve seat in converter

Replace primary valve seat.

Improper adjustment of power fuel mixture adjustment valve on LP-gas carburetor

Adjust power fuel mixture adjustment valve until appropriate acceleration performance is achieved.

Internal contamination of converter

Disassemble converter and clean internal parts.

Torn secondary diaphragm in converter

Replace diaphragm.

Power fuel mixture adjustment valve opening too large

Turn power fuel mixture adjustment valve slightly to (L) side.

Torn primary diaphragm in converter

Replace diaphragm.

Excessive tightening of power fuel mixture adjustment valve

Adjust power fuel mixture adjustment valve by turning to (R) side.

Insufficient opening (due to swelling of rubber in most cases) of solenoid valve

Replace solenoid valve.

Internal contamination of converter

Disassemble converter and clean internal parts.

Torn secondary diaphragm in converter.

Replace diaphragm.

Leaks in hose

Repair leaks.

Torn primary valve seat

Replace primary valve seat.

Insufficient power (gas mixture too rich or too lean)

Adjust power fuel mixture adjustment valve.

Insufficient power

Excessive gas

Excessive fuel consumption

Insufficient gas

Strong gas smell

Others

22

DISASSEMBLY AND REASSEMBLY 1. Main components of LP-gas device (4G15) Disassembly 3 8

4

7

6

2 5 1 10 13

11 9

14

12 13

206707

Disassembly sequence 1 Hot-water hose 2 Hot-water hose 3 Pipe 4 LP-gas hose 5 LP-gas hose 6 Vacuum hose 7 LP-gas converter and solenoid valve

8 9 10 11 12 13 14 23

Filter Blow-by hose Air hose Air hose Carburetor Fuel pipe (Gasoline) Solenoid valve (Gasoline)

DISASSEMBLY AND REASSEMBLY 2. Main components of LP-gas device (4G63, 4G64) Disassembly

3 8

4

7

6

2 5 1

10

13

14

11 9

12

13

206708

Disassembly sequence 1 Hot-water hose 2 Hot-water hose 3 Pipe 4 LP-gas hose 5 LP-gas hose 6 Vacuum hose 7 LP-gas converter and solenoid valve

8 9 10 11 12 13 14 24

Filter Blow-up hose Air hose Air hose Carburetor Fuel pipe (Gasoline) Solenoid valve (Gasoline)

DISASSEMBLY AND REASSEMBLY 3. Main components of LP-gas device (6G72) Disassembly

4

3 7 8 10 1 5 2

11 13

6

9

12

207418

Disassembly sequence 1 Hot-water hose 2 Hot-water hose 3 Filter 4 LP-gas hose

5 6 7 8

LP-gas hose Vacuum hose Pipe Conveter and solenoid valve 25

9 10 11 12 13

Cable Harness Air hose Air hose Carburetor

DISASSEMBLY AND REASSEMBLY 4. Disassembly and reassembly of LP-gas carburetor Disassembly Disassembly sequence 1 Screw (4) 2 Adapter 3 Gasket 4 Check valve plate 5 Air valve spring 6 Air valve sealing ring 7 Air valve 8 Air horn

8

7

Notes: (1) Parts indicated with an asterisk (À) are included in the repair kit.

(2) When carburetor is disassembled, be sure to replace gasket 3 with a new one during reassembly.

6

5

À

4

3

2

1 205131A

(1) With the LP-gas carburetor dismounted from the engine, remove four screws that mount the adapter on the air horn.

205408

26

DISASSEMBLY AND REASSEMBLY (2) Remove adapter.

205409

(3) Remove gasket.

205410

(4) Remove check valve plate and air valve spring.

Separate air valve from air horn.

205411

(5) Wash air horn with kerosene or high flesh point solvent.

– CAUTION Do not use LP-gas carburetor cleaner since it erodes synthetic rubber seals.

206709

27

DISASSEMBLY AND REASSEMBLY Reassembly (1) Take out parts from the repair kit.

Screws (4) Gasket (1) Check valve plate (1) Air valve sealing ring (1) Air valve (1) (2) Install sealing ring in piston groove.

(C)

– CAUTION Insert one end of sealing ring into piston groove, then coax the ring with a spiral movement to avoid breaking or creasing the ring.

Apply molybdenum disulfide grease on sections (A), (B) and (C) for smooth air valve movement.

(A)

206710

(3) Mount air valve on air horn.

Tilt air valve slightly to insert one end of the split sealing ring into the cylinder of air horn.

Then, using the tip of a pencil or other pointed tool, press the circumference of sealing ring to firmly mount the sealing ring and air valve on air horn.

(B)

206711

(4) Install air valve spring and check valve plate in the air horn.

206712

28

DISASSEMBLY AND REASSEMBLY (5) Position gasket in place, and press idle cutoff piston into the recess with thumb.

205412

(6) While holding gasket in place, insert adapter.

Be careful not to cover check valve with the gasket.

205413

(7) Lower adapter gently onto air horn. With adapter flush on the air horn, align holes and mount four screws tightly.

205414

(8) When assembly is complete, insert index finger into the air horn of carburetor and lift air valve several times to check its freedom of movement.

Air valve should lift easily and return slowly to the original position due to the action of check valve.

205416

29

DISASSEMBLY AND REASSEMBLY 5. Disassembly and reassembly of converter (vaporizer)

À COMPONENTS INCLUDED IN THE REPAIR KIT.

Disassembly 1

Disassembly sequence 1 Screw (6) 2 Secondary cover 3 Secondary diaphragm 4 Screw (1) 5 Secondary seat lever 6 Secondary seat Secondary seat pin 7 Fulcrum pin 8 Spring 9 Screw (7) 10 Primary cover 11 Primary diaphragm 12 Primary valve pin 13 Spring 14 Cover plate 15 Gasket 16 Primary valve seat 17 Converter body

2 3 4 5 6 7 8 17 À

16 15 14

Note: (1) Parts indicated with an asterisk (À) are included in the repair kit.

(2) When converter is disassembled, be sure to replace gasket 15 with a new one during reassembly.

13 12 11 10 9

205132

(1) Repair kit contains all necessary replacement parts to replace components subject to deterioration. All components in the repair kit should be used when overhauling converter or when converter has not been used for an extended period of time.

Converter gaskets and diaphragms deteriorate if converter is stored for a prolonged period after being used.

30

DISASSEMBLY AND REASSEMBLY (2) Start disassembly by removing secondary cover. Take out six screws, and tap the perimeter of the cover with the plastic handle of a screwdriver to loosen secondary cover from its mounting position.

206713

(3) Remove secondary diaphragm.

Slide secondary diaphragm toward gas inlet side to disengage diaphragm link from secondary seat lever.

206714

(4) At this stage, secondary seat lever is still positioned in link slot. Move secondary diaphragm to clear the slot.

206715

(5) Remove screw, and dismount secondary seat lever, secondary seat, secondary seat pin, fulcrum pin and spring from converter body.

Note that locating tabs for spring are provided on both sides of lever. These tabs, together with the tab on the top of lever, retain the spring in proper position and prevent it from slipping out of place.

206716

31

DISASSEMBLY AND REASSEMBLY (6) Take out seven screws, and remove primary cover and primary diaphragm.

Note rectangular lever riveted to primary diaphragm. This lever is supported on the upper side by a fulcrum cast in the cover.

The lever rocks on the fulcrum to depress primary valve pin and spring. In photo, the pencil points to pressure sensing port.

206717

(7) Primary valve is operated by primary valve pin that moves through a boss in the cover plate of converter body. This prevents diaphragm from contacting LP-gas, thus preventing diaphragm stiffening caused by refrigeration.

206718

(8) Illustration on the right shows converter with cover plate and gasket removed.

Located inside the body are serrated vaporizing chamber and heat exchange circuit which heats vaporized LP-gas.

206719

(9) In Illustration, the pencil points to aluminum alloy backing of primary valve in vaporizing chamber.

Viton sheet is bonded to this backing.

(10) Remove gasket from cover plate of converter body.

206720

32

DISASSEMBLY AND REASSEMBLY Reassembly (1) Take out parts from the repair kit.

Secondary diaphragm (1) Secondary seat (1) Secondary seat pin (1) Gasket (1) Primary valve pin (1) Primary diaphragm (1)

(2) Position gasket and cover plate of converter in place, and mount primary valve pin and spring.

206721

(3) Position primary cover, diaphragm and converter body cover plate in place, and tighten seven screws until they contact the cover. Then, tighten screws in a diagonal sequence until all screws are tightened evenly.

Note: Primary cover has marks that indicate positions of gas inlet, hot water inlet and outlet, and primary pressure check plug. Orifice located below the bottom mark is a vent for primary diaphragm.

206722

(4) Bend or straighten old secondary seat pin and remove secondary seat (right).

Replace with new secondary seat and secondary seat pin.

206723

33

DISASSEMBLY AND REASSEMBLY (5) Draw pin through secondary seat lever.

Pull the pin until the head of the pin contacts seat, but leave it loose enough so that seat can tilt to allow alignment with secondary jet.

206724

(6) Bend pin and hold seat in place.

Cut off excess part of the pin.

206725

(7) Install spring, and mount secondary seat lever with screw.

206726

(8) When installing secondary seat lever, insert secondary seat lever and fulcrum pin into the locating groove, and tighten screw to secure the parts in place.

206727

34

DISASSEMBLY AND REASSEMBLY (9) Align diaphragm link slot to the end section of secondary seat lever.

Gap from which link is punched should face gas inlet.

Refer to steps (3) and (4) of the disassembly procedure.

206728

(10) Position secondary diaphragm in place, and mount secondary cover with six screws.

Tighten screws until they contact secondary cover. Then, tighten screws from one side to the other until all screws are tightened evenly.

– CAUTION Use only brass fittings in the hot water inlet and outlet passages. Steel fittings cause casting to deteriorate due to electrolysis.

206729

– CAUTION After assembly in complete, conduct a pressure test using a soapy solution or testing solution to make sure there is no leak.

35

DISASSEMBLY AND REASSEMBLY 6. Disassembly and reassembly of LP-gas filter

– CAUTION 1. DO NOT use Teflon thread tape on any of the NPT pipe-thread fittings where fuel travels. Use a suitable fuelresistant joint compound.

2. Be sure to leak-check all fittings and covers for fuel tanks, using a soapy solution.

3. Be sure to use proper mounting bolts to secure the lockoff. Bolts which are too long may cause severe damage to the lockoff.

Disassembly

À COMPONENTS INCLUDED IN THE REPAIR KIT.

Disassembly sequence 1 Screw (10) 2 Filter cover 3 Gasket 4 Filter 5 Screen 6 Screw (1) 7 Valve spring 8 Valve seat 9 Valve operating pin 10 Retaining washer 11 O-ring lip seal 12 Screw (6) 13 Diaphragm cover 14 Diaphragm 15 Screw (2) 16 Fulcrum 17 Valve operating lever 18 Valve body

12 13 14 15 16 17 10

À

18 11 9 8 7 6 5 4 3 2 1 205399

36

DISASSEMBLY AND REASSEMBLY (1) Take out ten screws, and remove filter cover and gasket.

206732

(2) Remove filter and screen.

206733

(3) Take out screw, and remove valve spring.

(4) Remove valve seat and valve operating pin.

206730 206731

37

DISASSEMBLY AND REASSEMBLY (5) Diagram on the right shows the relationship of valve spring, valve seat, valve operating pin, seat retaining washer and O-ring.

When valve operating pin is removed, seat retaining washer can be taken out through the “Fuel Out” opening.

206734

(6) Insert wire through the “Fuel Out” jet hole, hook the wire on retaining washer, then pull it out.

206735

(7) Using the same wire, take out O-ring lip seal through the hole from which valve operating pin is removed in step (4).

Wash body, cover and jet as needed, using kerosene or cleaning oil. Do not use carburetor cleaner since it erodes synthetic rubber seals.

206736

(8) Take out six screws on diaphragm side, and remove diaphragm cover and diaphragm.

Wash parts as needed, using kerosene or cleaning oil.

Do not remove fulcrum or valve activating lever on diaphragm side.

206737

38

DISASSEMBLY AND REASSEMBLY Reassembly (1) Seat holder (H1-14236) should be positioned as shown in illustration (bottom tool).

Note that the hole in which the O-ring lip seal is installed is tapered, and that the wider end of the opening faces up.

Replacement seal must be coated with silicone grease before it is inserted into holder.

Place greased O-ring lip seal into the holder using installation pin (P1-14235), and re-coat seal with silicone grease.

The seal must be in the position shown in illustration, with groove facing up and visible.

Seal is tapered to match the hole in the holder.

Note: “H1-14236” and “P1-14235” are special tool numbers of Impco Company.

(2) With O-ring lip seal in the holder, groove visible and facing up, slide holder (with Oring lip seal) into the body.

Look through the fuel hole to check positioning of the seal. The seal must be positioned above the cavity of the seal recess.

Coat installation pin with silicone grease, and push seal through holder and into the seal recess of the body.

Remove installation pin, and look through the fuel hole to check for proper installation.

The seal should be seated in the seal recess, and groove should be visible.

INSTALLATION PIN

SEAT HOLDER

206738

206739

(3) Use needle nose pliers to install retaining washer through the “Fuel Out” opening.

Refer to the cross-sectional diagram for step (5) of the disassembly procedure.

206740

39

DISASSEMBLY AND REASSEMBLY (4) Coat valve operating pin with silicone grease, and insert in the body, so that pin passes through retaining washer and Oring lip seal. Rotate pin slowly to ease passage through washer and O-ring.

206741

(5) Place valve seat on top of the head of operating pin, with aluminum side facing up.

Make sure that Viton side is positioned towards the head of the pin.

206742

(6) Mount valve spring with screw. Lift valve spring slightly to confirm its freedom of movement.

206743

(7) Install screen and filter, place gasket, then mount filter cover with screws.

206744

40

DISASSEMBLY AND REASSEMBLY (8) Reassembly of diaphragm side Check valve operating lever for freedom of movement.

Use silicone grease to coat the surface of the gasket that contacts the body. Note that holes align only when the gasket is installed correctly.

Rivet heads on diaphragm should be on the cover side, not the body side.

206745

(9) Install diaphragm to the body, and mount diaphragm cover with screws.

Tighten screws evenly.

206746

41

INSPECTION AND ADJUSTMENT 1. LP-gas tank inspection Disassembly of components that are subject to high pressure, such as container, valve, level indicator device, must be performed by persons legally qualified and in shops certified under regulations. Request a certified shop to inspect the LP-gas tank.

2. Filter inspection (1) It is not necessary to check the filter unless the solenoid valve is defective. However, disassemble and clean the filter at least once a year.

(2) Parts replacement after filter disassembly With the parts contained in the repair kit, replace the filter, screen, gasket and other parts.

(3) Tighten the cover securely during the reassembly process.

After reassembly, check to make sure that there is no gas leak.

1 2 3 4 5 6 8

Components included in the Repair Kit. 1 Screw 3 Diaphragm 8 Retaining washer 9 O-ring lip seal 10 Valve operating pin 11 Valve seat 14 Screen 15 Filter 16 Gasket 18 Screw

À

À

7 9 10 11 12 13 14 15 16

3. Solenoid valve inspection (1) Start the engine. With the engine running, move the gasoline/LPG selector switch to a different position, and listen for a clicking sound. If no clicking sound is produced, clean or replace the solenoid valve.

17 18 205399

42

INSPECTION AND ADJUSTMENT 4. Converter (vaporizer) inspection and adjustment (1) Hot-water hose inspection The converter uses heat supplied by the engine cooling water to vaporize fuel.

Inspect the hot-water hoses for damage.

(2) Bleeding converter If hot water does not circulate properly, bleed the converter to remove air trapped in the water core.

To bleed the converter, remove the air vent plug on the side of the converter, and let the engine idle.

After making sure that intermittent flows of coolant with air from the plug hole have changed to a smooth flow, install the plug.

(Apply ThreeBond No. 1142 or equivalent sealant on plug threads.)

(3) Primary chamber pressure measurement Remove the plug located on the back side of the converter. Mount an R (PT) 1/4 connector and a pressure gauge to the pressure measuring port. Operate the engine with LP-gas. If the pressure indication shows a value from 9.8 to 14.7 kPa (0.1 to 0.15 kgf/cm2) [1.4 to 2.1 psi], it is normal.

If the pressure is less than 9.8 kPa (0.1 kgf/cm2) [1.4 psi], the engine lacks power on an upgrade inclination. If the pressure is higher than 14.7 kPa (0.15 kgf/cm2) [2.1 psi], the engine produces high output power but fuel consumption increases.

If the measured pressure is outside the specified range, disassemble the converter and replace the secondary seat.

43

AIR VENT PLUG

205134

REMOVE PLUG

205135

INSPECTION AND ADJUSTMENT 5. Idle speed adjustment After sufficient engine warm-up operation, adjust the idle fuel mixture adjustment screw of the LP-gas carburetor so that the engine idles at 650 to 700 rpm.

(1) Connect a tachometer.

Connect the positive (+) lead wire of the tachometer to the negative (-) terminal of the ignition coil, and the negative (-) lead wire to the vehicle chassis.

(2) Let engine idle.

(3) Set speed adjusting screw of the gasoline carburetor so that the engine runs at a speed of 600 to 650 rpm.

IGNITION COIL

202327

(4) Turn the idle fuel mixture adjustment screw of the LP-gas carburetor to the right until the engine operation becomes most stable.

Idle fuel mixture adjustment screw Open (turn to the left)

Fuel mixture condition

Engine condition

Lean

Unstable idling

Rich

High fuel consumption (Increases CO discharge and LP-gas smell)

Close (turn clockwise)

205136A

6. Output power adjustment Adjust the power fuel mixture adjustment valve on the LP-gas carburetor by following the procedure below.

(1) Turn the power fuel mixture adjustment valve toward the “L” side when the engine is operating under full load or working load.

(2) Turn the power fuel mixture adjustment valve slowly toward the “R” side. From the position at which the engine speed increases, further turn the power fuel mixture adjustment valve by 1 mm (0.039 in.) towards the “R” side.

Power fuel mixture adjustment valve

LP-gas

Turn toward “L” side

Lean

Turn toward “R” side

Rich

205137A

44

INSPECTION AND ADJUSTMENT 7. Ignition timing adjustment The combustion speed is different for gasoline and LP-gas. Therefore, the optimum ignition timing also differs.

When the engine operates mostly on LPgas, advance the ignition timing by 5° or 6° from the ignition timing for gasoline operation. This provides improved performance and better fuel economy.

8. Valve clearance adjustment For LP-gas operation, increase the clearance of the exhaust valves by 0.01 mm (0.00039 in.) from the standard value to compensate for greater heat expansion in exhaust valves resulting from the higher octane number of LP-gas.

Since high temperatures cause wearing of valves, the valve clearance changes over time. Adjust the valve clearance at least once every six months.

Note: In the engines (4G63, 4G64) of the 2 thru 3 ton class models, the valve clearance cannot be adjusted due to mechanical structure.

9. Gas leak check procedure (1) Open the gas outlet valve on the LP-gas tank.

(2) Set the gasoline/LPG selector to the [LPG] position.

(3) Turn the starter switch to the [START] position to start the engine.

(4) Use a gas leak tester or soapy solution to check the pipe joints for leaks.

45

Valve clearance (at operating temperature)

Intake

0.25 mm (0.00985 in.)

Exhaust

0.26 mm (0.0102 in.)

Periodic inspection interval

Every 6 months

INSPECTION AND ADJUSTMENT

Solenoid valve (dual fuel type)

Converter (Vaporizer)

LP-gas carburetor Low-pressure hoses (gas hoses) Hot-water hoses Engine

Every 4800 service hours or 2 years

LP-gas filter

Every 2400 service hours or 1 year

High-pressure hoses

Every 1200 service hours or 6 months

LP-gas tank and bracket

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Every 10 service hours or daily (pre-start)

item

Every 200 service hours or monthly

10. Periodic inspection schedule

service

Check bracket for installation.

Check bands for tightness.

Check valves and gauge for leaks.

Check hoses and fittings for damage.

Replace hoses.

Check for installation.

Check fuel lines for leaks.

Replace kit parts.

Check for installation.

Check fuel lines for leaks.

Check for function.

Remove tar.

Check connectors for tightness.

Check fuel lines for leaks.

Replace kit parts.

Check for installation.

Check fuel lines for leaks.

Replace kit parts.

Check for installation.

Check bands for tightness.

Check for damage.

Check bands for tightness.

Idling and acceleration CO measurement

46

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®

Lift Trucks

Service Manual Liquefied Petroleum Gas Supplement 4G63 4G64 6G72

AA0001-ZZ9999 AA0001-ZZ9999 0A0001-0Z9999

For use with 4G63, 4G64 & 6G72 Engine Service Manuals.

99729-85100

INTRODUCTION LP-gas (Liquefied Petroleum gas) lift trucks are superior to gasoline lift trucks in many ways including cleaner emissions and higher fuel efficiency.

LP-gas is, however, more dangerous than gasoline when handled improperly.

This Service Manual contains operating instructions and maintenance procedures for the LP-gas device of Caterpillar LP-gas fuel lift trucks. To ensure safety and maximize the superb features of your lift truck, read this manual thoroughly.

The following mark and designation are used in this manual to call your attention to important instructions and cautions.

< Warning indication > CAUTION

Note

Indicates items that users must always observe in order to prevent injuries and damage to the vehicle and surrounding area.

Supplementary explanation

99729-85100

TABLE OF CONTENTS Types of LP-gas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1 Guideline for selecting LP-gas for lift-truck engines . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1 LP-gas knock rating and octane number . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2 Adverse effects of olefins on LP-gas fuel system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2 Vapor pressure vs. temperature for mixture of propane and normal butane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2 Structure and Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4 1. Outline of LP-gas device . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4 2. LP-gas device layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5 3. Main component structures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6 3.1. LP-gas tank . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6 3.1.1. Pressure relief valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6 3.1.2. Fixed liquid level gauge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7 3.1.3. Service valve (LP-gas outlet valve) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7 3.1.4. Fuel level indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8 3.2. Filter (Vacuum fuel lock filter) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9 3.3. Hydrostatic relief valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10 3.4. Converter (vaporizer) and LP-gas carburetor . . . . . . . . . . . . . . . . . . . . . . . . . .11 3.4.1. Converter (vaporizer) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11 3.4..2. LP-gas carburetor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11 Actions to be taken in the event of a failure

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Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14 Disassembly and reassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17 1. Main components of LP-gas device (4G63, 4G64) . . . . . . . . . . . . . . . . . . . . . . . . . . . .17 2. Main components of LP-gas device (6G72) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18 3. Disassembly and reassembly of LP-gas carburetor /mixer . . . . . . . . . . . . . . . . . . . . . . .19 4. Disassembly and reassembly of converter/regulator (vaporizer) . . . . . . . . . . . . . . . . . .21 5. Disassembly and reassembly of LP-gas filter, Fuel lock . . . . . . . . . . . . . . . . . . . . . . . .27 Inspection and adjustment . . . . . . . . . .

1. LP-gas tank inspection . . . . . . . . . .

2. Filter inspection . . . . . . . . . . . . . . .

3. Converter (vaporizer) inspection and 4. Idle speed adjustment . . . . . . . . . .

5. Output power adjustment . . . . . . . .

6. Gas leak check procedure . . . . . . .

......... ......... ......... adjustment ......... ......... ......... i

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.33 .33 .33 .34 .35 .36 .36

CARB Tier 1 Emissions Control System (S-15G, 2001-2002 Model Year) Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1. Outline of CARB Tier 1 LP-gas system . . . . . . . . . . . . .

2. CARB Tier 1 LP-gas layout . . . . . . . . . . . . . . . . . . . . . .

3. Main Component Illustrations . . . . . . . . . . . . . . . . . . . .

3.1. Electronic Control Units (ECU) (Version 1 & 2) . . .

3.2. Electronic Control Unit Illustration . . . . . . . . . . . . .

3.3. Oxygen Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . .

3.4. Pedal Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3.5. Engine Block Temperature Sensor . . . . . . . . . . . .

3.6. Mixer and Throttle Body Illustration . . . . . . . . . . . .

3.7. Three Way Catalytic Convertor . . . . . . . . . . . . . . .

3.8. Dash Light Illustration . . . . . . . . . . . . . . . . . . . . . .

3.9. Exploded view for use with Pneumatic type models 3.10. Exploded view for use with cushion type models . .

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Systems Operations 1. Explanation of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46 Sub-system Operating Principles 1. Fuel Control . . . . . . . . . . . . . . .

2. Fuel Control Operation . . . . . . .

3. Throttle and Governor . . . . . . . .

4. Throttle and Governor Operation 5. Operating Specifications . . . . . .

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.46 .48 .49 .50 .50

System Adjustments 1. Diagnostic Kit Installation . . .

2. Adjustments . . . . . . . . . . . . .

3. S15G Screen Layout . . . . . . .

3.1 Adjustment Details . . . . .

3.2 Diagnostic Screen Layout

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.51 .51 .54 .55 .56

S-15G Troubleshooting 1. Troubleshooting Problem Detail .

2. Troubleshooting Tree Detail . . . .

3. Check Engine Light Blink Codes 4. System Fault Codes . . . . . . . . .

5. Effects of Fault Conditions . . . .

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ii

Vacuum System Diagram and Wiring Schematics 1. Vacuum System Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .65 2. S-15G Fuel System Wiring Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .66 3. ECU Pin Location and Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .67 Inspection and Adjustment 1. Periodic Inspection Schedule . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68

iii

TYPES OF LP-GAS LP-gases are commercial fuels. They are supplied in liquid form, so that they can be conveniently trans-ported, stored and used. They are mixtures of hydrocarbons, liquefied by pressurization. Though commercially classified as propane LP-gas, butane LP-gas and propanebutane mixture LP-gas, they contain other hydrocarbons (methane, ethane, ethylene, etc.) in small quantities. They are high in calorific value and, as fuel for automotive engines, can take the place of gasoline mainly because of their high octane number.

The simplest one is methane whose basic structure is composed of one carbon atom and four hydrogen atoms (C1H4); it is the first member of the paraffin series. The second is ethane (C2H6); the third, propane. (C3H8); the fourth, butane (C4H10); the fifth, pentane (C5H12), and so on. This series, otherwise called the alkane series, increases the number of hydrogen and carbon atoms according to the general formula CnH2n+2.

The olefin series is another: it starts out with ethylene (C2H4); followed by propylene (C3H6); butylene (C4H8); and so on, the general formula being CnH2n. For use as fuel, olefins are undesirable compounds for the reasons to be stated later.

Hydrocarbons, or compounds of hydrogen (H) with valence of 1 and carbon (C) with valence of 4, are truly many in kind.

STRUCTURE OF ETHYLENE (AN OLEFIN)

STRUCTURE OF METHANE (AN ALKANE)

206353

1. Be sure that the selected LP-gas is satisfactory with respect to vapor pressure*.

Since butane is a major hydrocarbon for LPgas, it may be well to note here that this alkane occurs in two molecular structures: one is normal butane with a boiling point of 0.6 °C (33.1 °F), and the other is isobutane with a b.p. of -10 °C (14.0 °F). Obviously the latter is more volatile.

2. Make sure that the selected LP-gas contains no olefins (unsaturated hydrocarbons) and, if it does, that the percent olefin content does not exceed the prescribed limit.

3. Make sure that the selected LP-gas contains no impurities

Guideline for selecting LP-gas for lifttruck engines

* We have seen that not all LP-gases are fit for use as engine fuel, and that ambient temperature has a great deal to do with LP-gas selection. The rules of thumbs are these:

1

“Vapor pressure” is a function of temperature and may be defined, Ioosely, as the pressure at or below which the liquid can turn to gas where its temperature is given. The v.p. of water at 0 °C (32.0 °F) is 0.5 mmHg (0.020 in.Hg), at 100 °C (212 °F), it is 760 mmHg (29.9 in.Hg) (=1 atm). This means that even a water of 0 °C (32.0 °F) can turn to vapor if the pressure acting on it is reduced to and under 0.5 mmHg (0.020 in.Hg).

TYPES OF LP-GAS Gasoline is volatile, so must be the LP-gas.

The yardstick of volatility is the vapor pressure.

Here resides the reason why the maximum vapor pressure is specified for each grade of LP-gas.

The LP-gas is contained in the supply tank at a pressure sufficiently higher than that of the atmosphere, so that, when its outlet valve is opened, it will flow out by its own pressure: this is one of the reasons why a pump is not used to forward it to the engine. Imagine a tank containing mostly butane and suppose that the tank gets chilled deep to drastically lower the temperature of its LP-gas inside. Then, the inside pressure will fall and the LP-gas might not flow out by its own pressure. Even if the butane came out, it might not turn to gas because its vapor pressure at low temperatures is low. The remedy in such a case is to use a more volatile LP-gas.

is called “addition reaction.” Ethylene molecules can combine to form a larger molecule, polyethylene, through “polymerization reaction.”

Propylene (C3H6) and butylene (C4H8), both olefins, are more reactive than ethylene and, if present in the LP-gas, are likely to form tar-like and rubbery substances and thus foul up the vaporizer, an important device in the LP-gas fuel system. Moreover, they are erosive: eroded diaphragms in the vaporizer are often explained by the presence of these olefins in the LP-gas.

Water and compounds of sulfur or sulfides as impurities can play the serious mischief with metal surfaces in the LP-gas fuel system by their corrosive action and also with the engine exhaust line by giving rise to sulfureous acid gas in the outgoing gases.

LP-gas knock rating and octane number As compared with gasoline, LP-gases are generally high in terms of anti-knock value and hence octane number. An LP-gas of nearly 100% propane is reported to have an octane number of well over 100; the octane number of the 100% butane is reported to range from 97 to 98, a level not far from that of what is sold as “premium gasoline” today.

The octane number of a fuel for the spark-ignition engine is a measure of its anti-knock quality: the higher the octane number, the less is the tendency of the fuel to knock.

Adverse effects of oleflns on LP-gas fuel system Olefins (unsaturated hydrocarbons) are trouble-makers: they are more prone to undergo chemical reactions. Take ethylene, the first and therefore simplest olefin of the series, for example: it can combine with chlorine gas (Cl2) to form ethylene dichloride through what 2

TYPES OF LP-GAS Vapor pressure vs. temperature for mixture of propane and normal butane The statement made earlier to the effect that “vapor pressure” of a liquid is a function of its temperature is graphically illustrated, below, for eleven mixtures of propane and normal butane in varied proportions.

Vapor pressure as gauge pressure MPa (kgf/cm2) [psi]

1.3 (13) [185] Propane C3H8

1.2 (12) [171]

Normal butane

C4H10

1.1 (11) [156]

1.0 (10) [142]

0.9 (9) [128]

0.8 (8) [114]

0.7 (7) [96]

0.6 (6) [85]

0.5 (5) [71]

0.4 (4) [57]

0.3 (3) [43]

0.2 (2) [28]

0.1 (1) [14]

0

-30 (-22)

-20 (-4)

-10 (14)

0 (32)

10 (50)

20 (68)

30 (86)

40 (104)

50 (122)

60 (140)

Temperature °C (°F) 202307

Vapor pressure vs. temperature 3

STRUCTURE AND FUNCTION 1. Outline of LP-gas device 1 5

3

2 4 Hot water

Hot water

Liquid LP-gas Vaporized LP-gas

8 6

7

Air (from air cleaner)

LP-gas + air

1 2 3 4

LP-gas tank LP-gas charge valve LP-gas outlet valve Vacuum fuel lock filter

5 6 7 8

Converter (vaporizer) LP-gas carburetor Vacuum hose LP Thermostat

4

205393A

STRUCTURE AND FUNCTION 2. LP-gas device layout

1

2

9

3

6 10

8

5 4

7 207150

1 LP-gas tank 2 LP-gas charge valve 3 LP-gas outlet valve

4 Vacuum fuel lock filter 5 Converter (vaporizer) 6 LP-gas carburetor

5

7 8 9 10

Hot-water hose Gas outlet hose Tank bracket Relief valve hydrostatic

STRUCTURE AND FUNCTION 3. Main component structures 3.1 LP-gas tank This tank is constructed as shown below. It has a service valve, a sight gauge, an elbow adapter with a raincap, a pressure relief valve, and a fixed liquid level gauge.

The tank is fastened securely to the bracket and needs to be covered to avoid its exposure to direct sunlight. Its fastening bands can be loosened to remove the tank when the engine is serviced.

2

3

1

4

5 206356

206367

“Exact version may vary depending on tank fitted.”

1 Service valve (liquid) 2 Elbow adapter with raincap and pressure relief valve

3 Fixed liquid level gauge 4 Plug (vapor) 5 Sight gauge

3.1.1 Pressure relief valve This relief valve is of fully internal “popaction” type and is located between the elbow adapter and tank body. This valve serves as a primary relief valve and reduces the possibility of foreign material which can prevent proper functioning of the relief mechanism. Its guide, stem and adjusting components are located within the tank — not exposed directly to foreign materials and debris from the atmosphere.

206358

6

STRUCTURE AND FUNCTION 3.1.2 Fixed liquid level gauge Having No. 54 drill size orifice, this gauge is for the LP-gas tank having a dip tube welded in the tank. It is also used where the tank is mounted at the maximum allowable filling level.

206359

3.1.3 Service valve (LP-gas outlet valve) The excess flow check valve located at the inlet consists of a spring, a valve disk complete with a stem, and a nozzle having a seat for the disk.

When the fuel flow rate is normal, the pressure acting on the face of the disk due to fuel velocity is not high, so that the spring keeps the disk pushed off the seat formed of the nozzle.

In the event of an excess flow rate caused, for instance, by failure of a hose connection, the pressure acting on the disk will be so high as to push in the disk against the force of the spring, thereby closing the nozzle to limit the flow of the fuel. This limiting action is due to the equalizing nozzle built in the disk.

The disk pushed against the nozzle will remain seated when a small amount of the fuel is flowing out through the equalizing nozzle but, as the pressure difference across the disk decreases and disappears, the spring will force the disk off to its normal lifted position.

7

206360

STRUCTURE AND FUNCTION 3.1.4 Fuel level indicator Just as the fuel gauge has a float in the gasoline tank, this indicator operates with its float in the LP-Gas tank. As the fuel level in the tank rises or falls, the float also rises or falls. This vertical movement of the float causes the sector shaft to rotate by an amount corresponding to the float movement.

In the head section of the indicator, which is secured to the tank shell, there are two permanent magnets. The one outside of the dial scale carries a needle, and the other is mounted on the end of the drive shaft. These magnets, between which lies a non-magnetic flange, are in such a position that, as the magnet on the drive shaft turns, the magnet on the dial scale turns by the same amount. The scale is calibrated to translate the position of the float into a percentage of the fuel in the tank. Thus, when the fuel level is halfway up, the needle will be at “50” to mean that the tank is 50% full.

6 1 3 5 2 4 206361

4 Float 5 Float rod 6 Counterweight

1 Plexiglas crystal 2 Head 3 Drive shaft

8

PRE CARB SYSTEM STRUCTURE AND FUNCTION 3.2 Filter (Vacuum fuel lock filter) The filter removes impurities contained in liquid LP-gas.

The filter can be removed for cleaning and replacement.

The hose connecting the filter and carburetor supplies negative pressure to the filter.

The valve provided on the filter opens when it receives negative pressure during engine startup, allowing LP-gas to flow.

When the engine is not operating, the lack of negative pressure closes the valve, thus stopping the LP-gas flow.

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

1 2 3 4 5 6 8 7

Screw (6) Diaphragm cover Diaphragm Screw (2) Fulcrum Valve operating lever Valve body Retaining washer O-ring lip seal Valve operating pin Valve seat Valve spring Screw (1) Screen Filter Gasket Filter cover Screw (10)

9 10 11 12 13 14 15 16 17 18 205399

9

STRUCTURE AND FUNCTION 3.3 Hydrostatic relief valve The hydrostatic relief valve is a simple spring loaded valve which is normally closed. A hydrostatic relief valve must be present in all fuel transfer lines between shutoffs. The hydrostatic relief valve must have a dust cap covering the outlet to prevent contamination of the valve.

The purpose of the hydrostatic relief valve is to protect the fuel transfer line from over pressure of not less than 400 psi/2.8 mPa and not more than 500 psi/3.5 mPa. When the pressure in the fuel transfer line exceeds the operating pressure of the hydrostatic relief valve, the valve is forced off of it’s seat allowing LPG to escape thus reducing the pressure in the fuel transfer line. When the pressure drops below the opening pressure of the hydrostatic relief valve, the valve closes.

10

PRE CARB SYSTEM STRUCTURE AND FUNCTION 3.4 Converter (vaporizer) and LP-gas carburetor 3.4.1 Converter (vaporizer) This converter is a water-heated, two-stage vaporizer. Fuel enters the converter at tank pressure as a liquid and its pressure is reduced to 9.8 to 14.7 kPa (0.1 to 0.15 kgf/cm2) [1.4 to 2.1 psi] within the primary or vaporizing chamber where it is converted from liquid to a gas.

Heat for vaporization is supplied from the engine cooling system.

3.4.2 LP-gas carburetor The LP-gas carburetor is a mixing valve that mixes the vaporized fuel and air. The gas metering valve is connected directly to the air valve so that the accurate gas-air ratios are maintained.

The purpose of the idle fuel mixture adjustment screw is to adjust the gas-air ratio for idling run of the engine. The power fuel mixture adjustment valve controls the gas flow through the LP-gas carburetor when the engine is loaded.

Gas then passes through the secondary valve which is controlled by the secondary diaphragm and flows into the secondary chamber where it is drawn off through the gas outlet to the LP-gas carburetor.

Liquid LP-gas

Primary seat Primary chamber LPgas pressure: 9.8 kPa (0.1 kgf/cm2) [1.4 psi]

Converter

Secondary diaphragm Water chamber Manual primer Atmospheric vent Secondary seat

Atmospheric vent

Air valve spring Air valve

Diaphragm

Secondary chamber

Primary diaphragm

Vaporized LP-gas Air (from air cleaner)

Idle fuel mixture adjustment screw

Power fuel mixture adjustment valve Idle fuel mixture adjustment valve

Power fuel mixture adjustment valve

Gas + air LP-gas carburetor 205397

11

ACTIONS TO BE TAKEN IN THE EVENT OF A FAILURE (1) When you smell the gas or notice something wrong with the LP-gas equipment during operation, immediately stop the lift truck in a safe area, turn the starter switch to “OFF” position, close the service valve (RED) of LP-gas tank, and try to find the cause. (It is advisable to have a test kit on hand for detecting gas leakage in the event of the failure.)

(2) If the internal pressure of LP-gas tank rises too high for one reason or another to cause the safety valve to open and let out the excess pressure, sprinkle water over the tank and, at the same time, extinguish the fire burning near the lift truck, if any, and ventilate the working area to rarefy the leakage gas.

(3) When gas leakage is evident, extinguish the fire burning near by and close the service valve (RED) of the tank as soon as possible.

(4) If there is a possibility of fire in the event of collision or overturning of the lift truck, close the service valve (RED) of the tank as soon as possible.

(5) The LP-gas tank installed in correct position will not explode even if it is in a blaze.

What to do in the event of emergency is to remove inflammable material from around the tank quickly.

(6) Use a dry-chemical (powder) type or carbon dioxide type extinguisher. Never use water. It is a good practice, however to sprinkle a large quantity of water over the LP-gas tank for cooling it down while extinguishing the fire.

(7) Only trained and authorized personnel should fill or exchange LP-gas tanks.

(8) Personnel engaged in filling of LP-gas tanks should wear protective clothing such as a face shield, long sleeves and gauntlet gloves.

(9) Do not refuel or store LP-gas powered lift trucks near any underground entrances, elevator shafts, or any other place where LP-gas could collect in a pocket causing a potentially dangerous condition.

(10) Do not leave the lift truck, for even a short period of time, in the vicinity of objects with high temperatures, such as ovens and furnaces. The heat may raise the pressure of the fuel and open the relief valve.

(11) Close the service valve on the tank when LP-gas fueled lift trucks are parked overnight or stored for a long period of time indoors with the fuel tank in place.

(12) Close the valves on empty tanks.

(13) Examine all LP-gas tanks before filling again before reuse, for damage to the valves, liquid gauge, fitting and hand wheels.

(14) Check for dents, scrapes or other damage to the pressure vessel and for dirt or debris in the openings.

(15) All defective or damaged LP-gas tanks must be removed from service.

(16) The careless handling of LP-gas tanks can result in a serious accident. Extreme care should be exercised when transporting tanks so that the tanks are not damaged.

(17) The storage and handling of liquid fuels in the U.S.A., should be in accordance with the NFPA No.30, “Flammable and Combustion Code.” Outside the U.S.A. store and handle in accordance with local regulations.

(18) The lift truck should be refueled only at designated safe locations. Safe outdoor locations are preferable to those indoors.

12

ACTIONS TO BE TAKEN IN THE EVENT OF A FAILURE (19) DO not completely fill the tank. The fuel expands when it gets warm and it may overflow. This will create a fire hazard.

(20) Only trained and authorized personnel should fill or exchange LP-gas tanks.

(21) Do not drop, throw, roll or drag LP-gas tanks. Do not strike LP-gas tanks or any associated parts of the tanks or fuel systems.

(22) Check the LP-gas tank for secure mount ing. Loose tanks can cause pressure fuel lines to leak, resulting in personal injury.

(23) Carefully read the caution labels.

(MCFA only)

“FUEL GAUGE” DECAL

“MAINTENANCE” DECAL

“L.P.G.” DECAL

“FUEL” DECAL 207151

13

PRE CARB TROUBLESHOOTING Engine does not start even though there is no equipment abnormality.

No LP-gas in tank

Refill LP-gas tank.

Be sure to open gas outlet valve on LP-gas tank.

Improper operating procedure

Do no use choke.

Do not press accelerator pedal all the way.

Overactivation of excess flow valve in gas outlet valve on LPgas tank

Close gas outlet valve (red handle) on LP-gas tank, and leave in that condition for about 1 minute. When gas pressure stabilizes and valve deactivates, open gas outlet valve.

Clogged filter

Disassemble and clean filter.

Difficulty in starting or failure to start

No LP-gas is supplied to converter.

Replace filter and screen.

Engine starts immediately.

but

Improper idle speed adjustment

Adjust idle fuel mixture adjustment screw on LP-gas carburetor.

Excessively low cooling water temperature

Use coolant.

Check for clogs in cooling water hoses and thermostat damage.

Insufficient gas pressure due to low temperature

If LP-gas tank pressure is lower than 98 kPa (1 kgf/cm2) [14.2 psi], increase propane content of LP-gas. (Ambient temperature: 0°C (32°F))

Malfunction of LP-gas carburetor

Check for sticking of air valve.

stalls

Others

If air valve sealing ring is worn, replace.

Mixing of air due to faulty connection of air hose to LP-gas carburetor

14

Use hose clamp to tighten the connection.

PRE CARB TROUBLESHOOTING

Faulty idling operation

Engine operation stops or is unstable at idle speed, or idle speed is too high.

Poor engine performance or stalling of engine

Others

Engine power decreases gradually during operation, and engine speed does not increase.

Engine stalls a short time after startup.

Strong gas smell

Improper setting of idle fuel mixture adjustment screw on LP-gas carburetor

Make adjustment.

Accumulation of rubber particles, oil and metal particles inside converter

Disassemble and clean.

Torn diaphragm in converter

Replace diaphragm.

Faulty secondary valve seat in converter

If valve does not completely rest on seat, replace seat.

Primary pressure exceeding 14.7 kPa (0.15 kgf/cm2) [2.1 psi] and, causing rich fuel mixture. (Damaged primary valve seat)

Replace primary valve seat.

No LP-gas

Refill with LP-gas. Exchange LP-gas tank.

Freezing of converter Hot water (engine cooling water) temperature is too low, or insufficient LP-gas

Remove hot-water hose at outlet to check if hot water is properly circulating (clogged hose).

Gas leaks from damaged LP-gas hose

Repair damaged hose.

Torn primary diaphragm in converter

Stop operation immediately, and replace primary diaphragm.

15

Poor acceleration

PRE CARB TROUBLESHOOTING Damaged primary valve seat in converter

Replace primary valve seat.

Improper adjustment of power fuel mixture adjustment valve on LP-gas carburetor

Adjust power fuel mixture adjustment valve until appropriate acceleration performance is achieved.

Internal contamination of converter

Disassemble converter and clean internal parts.

Torn secondary diaphragm in converter

Replace diaphragm.

Power fuel mixture adjustment valve opening too large

Turn power fuel mixture adjustment valve slightly to (L) side.

Torn primary diaphragm in converter

Replace diaphragm.

Excessive tightening of power fuel mixture adjustment valve

Adjust power fuel mixture adjustment valve by turning to (R) side.

Internal contamination of converter

Disassemble converter and clean internal parts.

Torn secondary diaphragm in converter.

Replace diaphragm.

Leaks in hose

Repair leaks.

Torn primary valve seat

Replace primary valve seat.

Insufficient power (gas mixture too rich or too lean)

Adjust power fuel mixture adjustment valve.

Insufficient power

Excessive gas

Excessive fuel consumption

Insufficient gas

Strong gas smell

Others

16

PRE CARB DISASSEMBLY AND REASSEMBLY 1. Main components of LP-gas device (4G63, 4G64) Disassembly 3

9 4

11 7 8 12 6 10

5 1

2

Hoses and other minor specifications are different for MCFE. 207152A

Disassembly sequence 1 Hot-water hose 2 Hot-water hose 3 Pipe 4 LP-gas hose 5 LP-gas hose 6 Vacuum hose

7 8 9 10 11 12

17

Vacuum hose LP-gas converter Filter Air hose Carburetor Thermostat

DISASSEMBLY AND REASSEMBLY 2. Main components of LP-gas device (6G72) Disassembly

12

4 3

13 8

7

6

5 10

11 1

2

9

10

207417

Disassembly sequence 1 Hot-water hose 2 Hot-water hose 3 Pipe 4 LP-gas hose 5 LP-gas hose 6 Vacuum hose

7 8 9 10 11 12 13 18

LP-gas converter Filter Air hose Blow-by hose Carburetor Hydrostatic relief valve LP-Gas hose to LPG tank

PRE CARB DISASSEMBLY AND REASSEMBLY 3. Disassembly and reassembly of LP-gas carburetor/ mixer (CAIOO) * COMPONENTS INCLUDED IN THE REPAIR KIT. DISASSEMBLY AND REASSEMBLY (1) Remove the air valve cover and retaining screw. Place a chalk mark on the air valve diaphragm and the mixer body. This mark will allow correct positioning during reassembly.

1 2

(2) Lift out and replace the air valve assembly in the mixer body.

3 4

(3) Press the air valve down until it bottoms into the body.

5

(4) Align the chalk mark on the air valve diaphragm with the chalk mark on the mixer body. Reassemble the air valve cover and install retaining screws.

6

* 7 8

13 10 12 11

9

14 15

14

16

205403

19

DISASSEMBLY AND REASSEMBLY (1) Remove the air valve cover and retaining screw. Place a chalk mark on the air valve diaphragm and the mixer body. This mark will allow correct positioning during reassembly.

Chalk mark

205404

(2) Lift out and replace the air valve assembly in the mixer body.

205405

(3) Press the air valve down until it bottoms into the body.

205406

(4) Align the chalk mark on the air valve diaphragm with the chalk mark on the mixer body. Reassemble the air valve cover and install retaining screws.

205407

20

PRE CARB DISASSEMBLY AND REASSEMBLY 4. Disassembly and reassembly of converter/ regulator (J) (vaporizer)

* COMPONENTS INCLUDED IN THE REPAIR KIT.

Disassembly 1 Disassembly sequence 1 Screw (6) 2 Secondary cover 3 Secondary diaphragm 4 Screw (1) 5 Secondary seat lever 6 Secondary seat Secondary seat pin 7 Fulcrum pin 8 Spring 9 Screw (7) 10 Primary cover 11 Primary diaphragm 12 Primary valve pin 13 Spring 14 Cover plate 15 Gasket 16 Primary valve seat 17 Converter body

2 3 4 5 6 7 8 17 ✱

16 15 14

Note

(1) Parts indicated with an asterisk (✱) are included in the repair kit.

(2) When converter is disassembled, be sure to replace gasket 15 with a new one during reassembly.

13 12 11 10 9 205132

(1) Repair kit contains all necessary replacement parts to replace components subject to deterioration. All components in the repair kit should be used when overhauling converter or when converter has not been used for an extended period of time.

Converter gaskets and diaphragms deteriorate if converter is stored for a prolonged period after being used.

21

DISASSEMBLY AND REASSEMBLY (2) Start disassembly by removing secondary cover. Take out six screws, and tap the perimeter of the cover with the plastic handle of a screwdriver to loosen secondary cover from its mounting position.

206713

(3) Remove secondary diaphragm.

Slide secondary diaphragm toward gas inlet side to disengage diaphragm link from secondary seat lever.

206714

(4) At this stage, secondary seat lever is still positioned in link slot. Move secondary diaphragm to clear the slot.

206715

(5) Remove screw, and dismount secondary seat lever, secondary seat, secondary seat pin, fulcrum pin and spring from converter body.

Note that locating tabs for spring are provided on both sides of lever. These tabs, together with the tab on the top of lever, retain the spring in proper position and prevent it from slipping out of place.

206716

22

DISASSEMBLY AND REASSEMBLY (6) Take out seven screws, and remove primary cover and primary diaphragm.

Note rectangular lever riveted to primary diaphragm. This lever is supported on the upper side by a fulcrum cast in the cover.

The lever rocks on the fulcrum to depress primary valve pin and spring. In illustration, the pencil points to pressure sensing port.

206717

(7) Primary valve is operated by primary valve pin that moves through a boss in the cover plate of converter body. This prevents diaphragm from contacting LP-gas, thus preventing diaphragm stiffening caused by refrigeration.

206718

(8) Illustration on the right shows converter with cover plate and gasket removed.

Located inside the body are serrated vaporizing chamber and heat exchange circuit which heats vaporized LP-gas.

206719

(9) In illustration, the pencil points to aluminum alloy backing of primary valve in vaporizing chamber.

Viton sheet is bonded to this backing.

(10) Remove gasket from cover plate of converter body.

206720

23

DISASSEMBLY AND REASSEMBLY Reassembly (1) Take out parts from the repair kit.

Secondary diaphragm (1) Secondary seat (1) Secondary seat pin (1) Gasket (1) Primary valve pin (1) Primary diaphragm (1)

(2) Position gasket and cover plate of converter in place, and mount primary valve pin and spring.

206721

(3) Position primary cover, diaphragm and converter body cover plate in place, and tighten seven screws until they contact the cover. Then, tighten screws in a diagonal sequence until all screws are tightened evenly.

Note: Primary cover has marks that indicate positions of gas inlet, hot water inlet and outlet, and primary pressure check plug. Orifice located below the bottom mark is a vent for primary diaphragm.

206722

(4) Bend or straighten old secondary seat pin and remove secondary seat (right).

Replace with new secondary seat and secondary seat pin.

206723

24

DISASSEMBLY AND REASSEMBLY (5) Draw pin through secondary seat lever.

Pull the pin until the head of the pin contacts seat, but leave it loose enough so that seat can tilt to allow alignment with secondary jet.

206724

(6) Bend pin and hold seat in place.

Cut off excess part of the pin.

206725

(7) Install spring, and mount secondary seat lever with screw.

206726

(8) When installing secondary seat lever, insert secondary seat lever and fulcrum pin into the locating groove, and tighten screw to secure the parts in place.

206727

25

DISASSEMBLY AND REASSEMBLY (9) Align diaphragm link slot to the end section of secondary seat lever.

Gap from which link is punched should face gas inlet.

Refer to steps (3) and (4) of the disassembly procedure.

206728

(10) Position secondary diaphragm in place, and mount secondary cover with six screws.

Tighten screws until they contact secondary cover. Then, tighten screws from one side to the other until all screws are tightened evenly.

CAUTION

Use only brass fittings in the hot water inlet and outlet passages. Steel fittings cause casting to deteriorate due to electrolysis.

206729

CAUTION

After assembly in complete, conduct a pressure test using a soapy solution or testing solution to make sure there is no leak.

26

PRE CARB DISASSEMBLY AND REASSEMBLY 5. Disassembly and reassembly of LP-gas filter, fuel lock (VFF30)

CAUTION 1. DO NOT use Teflon thread tape on any of the NPT pipe-thread fittings where fuel travels. Use a suitable fuel resistant joint compound.

2. Be sure to leak-check all fittings and covers for fuel tanks, using a soapy solution.

3. Be sure to use proper mounting bolts to secure the lockoff. Bolts which are too long may cause severe damage to the lockoff.

Disassembly * COMPONENTS INCLUDED IN THE REPAIR KIT.

Disassembly sequence 1 Screw (10) 2 Filter cover 3 Gasket 4 Filter 5 Screen 6 Screw (1) 7 Valve spring 8 Valve seat 9 Valve operating pin 10 Retaining washer 11 O-ring lip seal 12 Screw (6) 13 Diaphragm cover 14 Diaphragm 15 Screw (2) 16 Fulcrum 17 Valve operating lever 18 Valve body

12 13 14 15 16 17 10

✱

18 11 9 8 7 6 5 4 3 2 1 205399

27

DISASSEMBLY AND REASSEMBLY (1) Take out ten screws, and remove filter cover and gasket.

206730

(2) Remove filter and screen.

206731

(3) Take out screw, and remove valve spring.

206732

(4) Remove valve seat and valve operating pin.

206733

28

DISASSEMBLY AND REASSEMBLY (5) Diagram on the right shows the relationship of valve spring, valve seat, valve operating pin, seat retaining washer and O-ring.

When valve operating pin is removed, seat retaining washer can be taken out through the “Fuel Out” opening.

206734

(6) Insert wire through the “Fuel Out” jet hole, hook the wire on retaining washer, then pull it out.

206735

(7) Using the same wire, take out O-ring lip seal through the hole from which valve operating pin is removed in step (4).

Wash body, cover and jet as needed, using kerosene or cleaning oil. Do not use carburetor cleaner since it erodes synthetic rubber seals.

206736

(8) Take out six screws on diaphragm side, and remove diaphragm cover and diaphragm.

Wash parts as needed, using kerosene or cleaning oil.

Do not remove fulcrum or valve activating lever on diaphragm side.

206737

29

DISASSEMBLY AND REASSEMBLY Reassembly (1) Seat holder (H1-14236) should be positioned as shown in illustration (bottom tool).

Note that the hole in which the O-ring lip seal is installed is tapered, and that the wider end of the opening faces up.

Replacement seal must be coated with silicone grease before it is inserted into holder.

Place greased O-ring lip seal into the holder using installation pin (P1-14235), and re-coat seal with silicone grease.

The seal must be in the position shown in illustration, with groove facing up and visible. Seal is tapered to match the hole in the holder.

Note

INSTALLATION PIN

SEAT HOLDER

206738

“H1-14236” and “P1-14235” are special tool numbers of Impco Company.

(2) With O-ring lip seal in the holder, groove visible and facing up, slide holder (with Oring lip seal) into the body.

Look through the fuel hole to check positioning of the seal. The seal must be positioned above the cavity of the seal recess.

Coat installation pin with silicone grease, and push seal through holder and into the seal recess of the body.

Remove installation pin, and look through the fuel hole to check for proper installation.

The seal should be seated in the seal recess, and groove should be visible.

206739

(3) Use needle nose pliers to install retaining washer through the “Fuel Out” opening.

Refer to the cross-sectional diagram for step (5) of the disassembly procedure.

206740

30

DISASSEMBLY AND REASSEMBLY (4) Coat valve operating pin with silicone grease, and insert in the body, so that pin passes through retaining washer and Oring lip seal. Rotate pin slowly to ease passage through washer and O-ring.

206741

(5) Place valve seat on top of the head of operating pin, with aluminum side facing up.

Make sure that Viton side is positioned towards the head of the pin.

206742

(6) Mount valve spring with screw. Lift valve spring slightly to confirm its freedom of movement.

206743

(7) Install screen and filter, place gasket, then mount filter cover with screws.

206744

31

DISASSEMBLY AND REASSEMBLY (8) Reassembly of diaphragm side Check valve operating lever for freedom of movement.

Use silicone grease to coat the surface of the gasket that contacts the body. Note that holes align only when the gasket is installed correctly.

Rivet heads on diaphragm should be on the cover side, not the body side.

206745

(9) Install diaphragm to the body, and mount diaphragm cover with screws.

Tighten screws evenly.

206746

32

PRE CARB INSPECTION AND ADJUSTMENT 1. LP-gas tank inspection Disassembly of components that are subject to high pressure, such as container, valve, level indicator device, must be performed by persons legally qualified and in shops certified under regulations. Request a certified shop to inspect the LP-gas tank.

2. Filter inspection (1) Parts replacement after filter disassembly With the parts contained in the repair kit, replace the filter, screen, gasket and other parts.

(2) Tighten the cover securely during the reassembly process.

After reassembly, check to make sure that there is no gas leak.

1 2 3 4 5 6 8

* Components included in the Repair Kit. 1 Screw 3 Diaphragm 8 Retaining washer 9 O-ring lip seal 10 Valve operating pin 11 Valve seat 14 Screen 15 Filter 16 Gasket 18 Screw

✱

7 9 10 11 12 13 14 15 16 17 18 205399

33

INSPECTION AND ADJUSTMENT 3. Converter (vaporizer) inspection and adjustment (1) Hot-water hose inspection The converter uses heat supplied by the engine cooling water to vaporize fuel.

Inspect the hot-water hoses for damage.

(2) Bleeding converter If hot water does not circulate properly, bleed the converter to remove air trapped in the water core.

To bleed the converter, remove the air vent plug on the side of the converter, and let the engine idle.

After making sure that intermittent flows of coolant with air from the plug hole have changed to a smooth flow, install the plug.

(Apply ThreeBond No. 1142 or equivalent sealant on plug threads.)

AIR VENT PLUG

205134

(3) Primary chamber pressure measurement Remove the plug located on the back side of the converter. Mount an R (PT) 1/4 connector and a pressure gauge to the pressure measuring port. Operate the engine with LP-gas. If the pressure indication shows a value from 9.8 to 14.7 kPa (0.1 to 0.15 kgf/cm2) [1.4 to 2.1 psi], it is normal.

If the pressure is less than 9.8 kPa (0.1 kgf/cm2) [1.4 psi], the engine lacks power on an upgrade inclination. If the pressure is higher than 14.7 kPa (0.15 kgf/cm2) [2.1 psi], the engine produces high output power but fuel consumption increases.

If the measured pressure is outside the specified range, disassemble the converter and replace the secondary seat.

REMOVE PLUG

205135

34

INSPECTION AND ADJUSTMENT 4. Idle speed adjustment After sufficient engine warm-up operation, adjust the idle fuel mixture adjustment screw of the LP-gas carburetor so that the engine idles at 650 to 700 rpm.

(1) Connect a tachometer.

Connect the positive (+) lead wire of the tachometer to the negative (-) terminal of the ignition coil, and the negative (-) lead wire to the vehicle chassis.

IGNITION COIL

202327

(2) Let engine idle.

(3) Turn the idle fuel mixture adjustment screw of the LP-gas carburetor to the right until the engine operation becomes most stable.

Idle fuel mixture adjustment screw Open (turn to the left)

Fuel mixture condition

Engine condition

Lean

Unstable idling

Close (turn clockwise)

Rich

High fuel consumption (Increases CO discharge and LP-gas smell)

PRELIMINARY POWER VALVE SETTING

205398

ENGINE

TIMING BTDC

LOW IDLE RPM %CO

STALL RPM %CO

4G63

9° ± 1°

4G63 Optional 4G64

@ 650˜

1920 ± 100

4G64

700 RPM

1920 ± 100

4G63

9° ± 1°

2080 ± 100

4G63 Optional 4G64

@ 650˜

1910 ± 100

4G64

700 RPM

1910 ± 100

6G72

9° ± 1° @ 650˜ 700 RPM

HIGH IDLE RPM %CO

2070 ± 100 650 ˜ 700

650 ˜ 700

0.2 ˜ 0.8%

0.2 ˜ 0.8%

1740 ± 100 0.3 ˜ 0.8%

1730 ± 100 0.3 ˜ 0.8%

2550 ˜ 2700

0.8% MAX.

2550 ˜ 2700

0.8% MAX.

650 ˜ 700 0.05 ˜ 0.25% 1800 ± 100 0.4 ˜ 0.9% 2550 ˜ 2600

35

0.9% MAX.

INSPECTION AND ADJUSTMENT 5. Output power adjustment Set the power fuel mixture adjustment valve as shown below.

(1) If the power fuel mixture adjustment valve is turned toward “L” side, the power mixture becomes lean, resulting in lack of power.

(2) If the power fuel mixture adjustment valve is turned toward the “R” side, the power mixture becomes rich, resulting in excessive exhaust gases and CO and lack of power.

Power fuel mixture adjustment valve

205398A

6. Gas leak check procedure (1) Open the gas outlet valve on the LP-gas tank.

(2) Turn the starter switch to the START position to start the engine.

(3) Use a gas leak tester or soapy solution to check the pipe joints for leaks.

36

STRUCTURE AND FUNCTION

CARB T ier 1 Emissions C ontrol S ystem The California Air the state’s state’s environThe California AirResources Resources Board Board (CARB) (CARB) is is the mental regulatory agency. agency.

CARB has issued emissions regulations environmental regulatory CARB has issued emissions for certain types of industrial not already covered regulations for certain typesequipment of industrial equipment not by existalready by existing EPAregulation regulations.

This new regu- using ing EPAcovered regulations.

This new impacts vehicles lation impacts vehicles using “large “large spark-ignited” engines above spark-ignited” 25 horsepower,engines including lift above 25 horsepower, including lift trucks.

The term “sparktrucks.

The term “sparkignited” includes all engines using gasoline, ignited” includes all engines using gasoline, LP, and related LP, and related fuel types, such as Compressed Natural Gas. The fuel types, applies such asonly Compressed Natural Gas. The regulation regulation to new equipment, starting with units proapplies only to new equipment, starting with units produced duced in year 2001, and does not require existing equipment to be in year 2001, and does not require existing equipment to be modified to meet the new emissions standards. modified to meet the new emissions standards.

The CARB regulations regulations require require lift lift truck The CARB truck manufacturers manufacturerstotomodify a percentage of the trucks sold into California, in year 2001, modify a percentage of the trucks sold intobeginning California, to incorporate an emissions control system (ECS) which will achieve beginning in year 2001, to incorporate an emissions control system (ECS) whichlevels will achieve emissions levels exhaust emissions defined exhaust within the regulations.

In the foldefinedyears, within regulations.

In thesold following years, the lowing thethe percentage of trucks with emissions reduction percentage of trucks sold with emissions reduction technology technology must increase each year until 2004, when the entire must increaseengine each year when thecompliant. entire sparksparkignited line until must 2004, be emissions This initial ignited engine line must be emissions compliant.

This initial phase-in period is designated “Tier 1”, and defines exhaust emisphase-in period which is designated 1”, and defines exhaust at the sions standards must be “Tier achieved by the manufacturer emissions standards which“Tier must achievedwill by take the manutime of shipment.

In 2004, 2” be regulations effect, with a facturer at the time of shipment. In 2004, “Tier 2” regulations proposal by the EPA to adopt this as a nationally-legislated standard. will take effect, with a proposal by the EPA to adopt this as a The emissions standards and phase-in percentages are and shown in nationally-legislated standard.

The emissions standards the chart below. phase-in percentages are shown in the chart below.

Effective Date Emissions Limits CO (g/hp-hr) HC + NOx Useful Life / Durability Testing Emissions Limits (g/hp-hr)

Tier 1 CARB

Tier 2 CARB

Jan 2001 to Dec 2003 37 3

Jan 2004 to Dec 2006 37 3 3500hr/5yr 50 CO 4 HC + NOx

N/A

Warranty Period- Components

Phase-In % Production Line Testing In-Use Testing System Adjustment Tampering

< $400 > $400 2001 2002 2003

1500hr / 2yr 1500hr / 2yr 25% CA Sales 50% CA Sales 75% CA Sales Required N/A Resistant

37

2500hr / 3yr 3500hr / 5yr 100% USA Required Required Tamper-Proof

STRUCTURE AND FUNCTION

1. Outline of CARB Tier 1 LP-gas system

Function of components

38

STRUCTURE AND FUNCTION 2. CARB Tier 1 LP-gas layout (2001-2002 Model Year)

Mixer Throttle Body LP Filter

FCSV

Fuel Lock 0ff Vaporizer

Location of components on truck

CARB Label

39

STRUCTURE AND FUNCTION 3. Main Component Illustrations 3.1 Electronic Control Unit (ECU) Identification of ECU is shown in examples below

version 1

version 2

3.2. Electronic Control Unit (ECU)

40

STRUCTURE AND FUNCTION 3.3. Oxygen sensor mounted in exhaust manifold

3.4. Pedal Sensor

3.5 Engine Block Temperature Sensor

41

STRUCTURE AND FUNCTION 3.6. Mixer and Throttle Body Illustration LP GAS VALVE CARBURETOR INTERNAL GAS FLOW PART LOAD METERING VALVE NON ADJUSTABLE Pressure Transfer holes Metering Spring Diaphragm FCSV Air Measuring Valve Fuel Metering Valve LP Gas (Vapor) From Regulator

Air

IDLE AIR ORIFICE NON ADJUSTABLE

Vacuum Advance Port

Map Electronic Throttle body

3.7. Three Way Catalytic Converter

42

STRUCTURE AND FUNCTION 3.8 Dash Light Illustration

Transmission Fluid level Low Oil Charging System Oil Temp Brake Pressure

43

Check Engine

STRUCTURE AND FUNCTION 3.9. Exploded view for use with Pneumatic type models

1 2 3 4

LPG Converter Fuel Lock Filter Fuel Control Solenoid Valve ECU

5 6 7 8 44

Mixer Oxygen Sensor Throttle Body Vacuum Lines

STRUCTURE AND FUNCTION 3.10 Exploded view for use with cushion type models

1 2 3 4

LPG Converter Vacuum Lines Fuel Lock Filter Fuel Control Solenoid Valve

5 6 7 8 45

ECU Throttle Body Mixer Oxygen Sensor

STRUCTURE AND FUNCTION 2. Terminology Engine management systems use a variety of acronyms and system specific terms. The following list of terms and acronyms are used in the CARB 1 Tier 1 system. (Reference SAE J1330 terminology.)

Systems Operation 1. Explanation of Operation 4G63 (2.0 L.) & 4G64 (2.4 L.) LPG closed loop fuel control system with 3 way catalyst.

Regulatory Background: MCFA has developed an emissions-compliant control system. The control system is a closedloop system with a 3-way catalytic converter as standard. It utilizes electronic fuel delivery with "drive-by-wire" throttle and governor control. The key system component is the Electronic Control Unit (ECU) that monitors various sensors on the truck, and controls engine performance to pre-programmed specifications. The two main sub-systems are: • Fuel control • Throttle and governor control The benefit to the user is a vast improvement in indoor air quality, engine drivability and performance, maintenance and fuel economy.

A/F BAT CAT ECU EGO ET

Air Fuel Mixture Battery Voltage Catalytic Converter Electric Control Unit Exhaust Gas Oxygen Sensor Engine Temperature (Engine block temp.)

FCSV Fuel Control Solenoid Valve MAP Manifold Absolute Pressure OXY Oxygen RPM Engine Revolutions per Min. SFL System Fault Light SFC System Fault Code

Sub-system Operating Principles 1. Fuel Control: The fuel control system utilizes a "closed loop" fuel control strategy. The "Closed loop" method is used to calculate the correct air and fuel mixture ratio (A/F) based on ECU programming using data collected from sensor inputs while the engine is operating. This sub-system monitors four engine parameters and transmits this information to the ECU. The ECU is able to adjust the fuel supply by varying the output to the fuel control solenoid valve (FCSV). The inputs and output for this subsystem are as follows: 1) Engine manifold pressure (MAP) is an indicator of engine load. Higher loads result in a numerically higher MAP value.

2) Engine speed to indicate current engine revolutions per minute (RPM)

46

STRUCTURE AND FUNCTION 2. Terminology Engine management systems use a variety of acronyms and system specific terms. The following list of terms and acronyms are used in the CARB 1 Tier 1 system. (Reference SAE J1330 terminology.)

Systems Operation 1. Explanation of Operation 4G63 (2.0 L.) & 4G64 (2.4 L.) LPG closed loop fuel control system with 3 way catalyst.

Regulatory Background: MCFA has developed an emissions-compliant control system. The control system is a closedloop system with a 3-way catalytic converter as standard. It utilizes electronic fuel delivery with "drive-by-wire" throttle and governor control. The key system component is the Electronic Control Unit (ECU) that monitors various sensors on the truck, and controls engine performance to pre-programmed specifications. The two main sub-systems are: • Fuel control • Throttle and governor control The benefit to the user is a vast improvement in indoor air quality, engine drivability and performance, maintenance and fuel economy.

A/F BAT CAT ECU EGO ET

Air Fuel Mixture Battery Voltage Catalytic Converter Electric Control Unit Exhaust Gas Oxygen Sensor Engine Temperature (Engine block temp.)

FCSV Fuel Control Solenoid Valve MAP Manifold Absolute Pressure OXY Oxygen RPM Engine Revolutions per Min. SFL System Fault Light SFC System Fault Code

Sub-system Operating Principles 1. Fuel Control: The fuel control system utilizes a "closed loop" fuel control strategy. The "Closed loop" method is used to calculate the correct air and fuel mixture ratio (A/F) based on ECU programming using data collected from sensor inputs while the engine is operating. This sub-system monitors four engine parameters and transmits this information to the ECU. The ECU is able to adjust the fuel supply by varying the output to the fuel control solenoid valve (FCSV). The inputs and output for this subsystem are as follows: 1) Engine manifold pressure (MAP) is an indicator of engine load. Higher loads result in a numerically higher MAP value.

2) Engine speed to indicate current engine revolutions per minute (RPM)

46

STRUCTURE AND FUNCTION 3)

4)

Oxygen sensor mounted in the exhaust manifold. This sensor produces a voltage, based on the oxygen content of the exhaust stream, to indicate the current A/F. Engine temperature to indicate the fuel requirements for cold starting, general operation, and as a monitor of proper engine functional condition.

Note: These parameters can be monitored during engine operation using the diagnostic tools, as described in the troubleshooting section.

INPUT (To ECU) MAP (Manifold Absolute Pressure) RPM (Engine RPM) OXY (Oxygen Sensor Voltage) ET (Engine Block Temperature)

OUTPUT (From ECU) FCSV (Fuel Control Solenoid Valve)

Note: See Wiring Schematic section for wiring locations and wire colors.

47

STRUCTURE AND FUNCTION 2. Fuel Control Operation: When the operator turns the key to start the engine, the ECU power supply is activated.

After the engine starts the distributor provides a signal to the ECU by a connection in the wiring harness that provides the current RPM. Once the ECU detects a RPM, a ground circuit is activated to the electronic LP lock off, to "open" the valve and allows the LP gas to begin flowing. The electronic LP lock off is normally closed when the engine is not running.

Upon start-up the ECU monitors for engine temperature and will adjust the air-fuel control valve rich to compensate for the cold engine.

The idle RPM is increased (over the base idle set speed of 700RPM) during the warm-up period. During the warm-up period, the A/F ratio is determined by presets in the ECU and not influenced by the oxygen sensor. This is called “Open Loop mode”. The engine will NOT operate in "closed loop" fuel control until the following conditions have occurred.

1) Engine must be warmed to operating temperature.

2) The operator must have applied accelerator input causing the engine RPMs to exceed 2000 RPMs for a brief period of time.

Once the engine is operating in closed loop mode, the ECU will begin to actively adjust the fuel flow to keep the A/F ratio at stoichiometric.

Stoichiometric is the A/F ratio that allows maximum combustion efficiency and allows the catalytic converter to minimize the exhaust pollutants. If the A/F ratio is not kept at stoichiometic, the catalyst will not operate correctly. If the ECU detects that the closed loop control system is not operating correctly and the A/F ratio is not in the normal range for longer than 90 continuous seconds, the check engine light will illuminate and a "limp home" feature is activated and the maximum engine RPM is limited to 1800. If the engine is operated at high RPMs and high hydraulic use or intense driving demands while the closed loop fuel control system is not operating properly, damage to 48

the catalyst may result. When the ignition switch is turned off, the error recorded by the ECU is reset. The S-15G ECU does not store error codes. Upon restart, the engine will operate normally unless an error is again detected.

Periodic illumination of the check engine light does not necessarily indicate a fuel control system malfunction. Poor fuel quality, improper system operation and running an LP tank dry can also cause a "closed loop" error which will be displayed on the diagnostic monitors as an "OXY" code.

By monitoring changes in MAP and RPM the ECU can determine the engine load, if the engine is accelerating or decelerating the ECU will calculate a suitable increase or decrease in A/F to match the engine condition. The fuel flow is controlled by the Fuel Control Solenoid Valve (FCSV). The FCSV is a 12 volt electrically operated solenoid valve that is inline between the vacuum port on the mixer and the regulator converter assembly. The FCSV is normally in the closed position when no voltage is provided.

The mixer, the FCSV, and the regulator are connected by a network of vacuum lines. The FCSV operates at specific "DWELL" based on fuel requirements. A 50% dwell means the valve is open 50% of the time and closed 50% of the time. A DWELL of 100% indicates that the valve is open 100% of the time and the fuel control system is at full "lean". A DWELL of 0% indicates that the valve is closed 100% of the time and the fuel control system is full "rich". Normally, the FCSV will operate at a DWELL between 20-80 depending on local atmospheric factors, engine temperature, operating conditions, and fuel quality. As the FCSV opens it allows engine vacuum, as supplied by the vacuum port on the mixer, to reach the diaphragm chamber on the regulator converter assembly. As this engine vacuum reaches the diaphragm chamber, it "pulls" on the diaphragm which in turn reduces the fuel pressure supplied to the engine. The reduction in

STRUCTURE AND FUNCTION fuel pressure has the effect of reducing the amount of fuel flow to the engine. As the DWELL of the FCSV is varied during operation, and based on input information the ECU processes, the fuel flow is adjusted accordingly. Any unapproved alteration to the vacuum lines, FCSV, and associated check valves (not described in this section) may cause the fuel control system to malfunction. Engine and catalyst damage may result and may void the manufacturer’s warranty.

Note: If during a service attempt, an ECU is not operating as described in this manual contact your local authorized Caterpillar Lift Truck dealer. Please note the truck serial number and prepare a detailed explanation of the operating characteristics prior to contacting dealer.

3. Throttle and Governor: The throttle and governor sub-system utilizes a "drive by wire" electronic throttle body. The electronic throttle body is a single "electromechanical" component. The electronic throttle body has 2 electric coils and a shaft mounted mechanical throttle valve. When voltage is applied to the coils, the shaft with the throttle valve will rotate. The throttle valve is mounted in the intake passage. As the voltage to the coils is increased, the shaft rotates opening the throttle valve, and allows increased airflow to the engine which increases the RPM. INPUT (To ECU) Throttle sensor RPM MAP

OUTPUT (From ECU) Voltage to electronic throttle body

The electronic throttle body has full authority over the throttle valve at all engine speeds and loads. The ECU will only allow the engine to operate in the manner it was programmed, and neither the operator nor service technician can alter the operating characteristic of this system without causing system failures. Idle RPM is 700. Maximum RPM is 2700. The system 49

utilizes a throttle sensor which is connected to the foot pedal either by a bracket and rod or a throttle cable, depending on the specific truck model.

Regardless of the specific throttle sensor used, the operating principals are the same. The throttle sensor includes a component called a potentiometer which relays a variable voltage to the ECU. As the potentiometer is rotated the voltage increases. The potentiometer has a voltage range from 0 volts to a maximum of 5 volts. (The minimum voltage at idle should never be less than .2 volts or at full pedal stop bolt position more than 4.865 volts.) As the operator depresses the foot pedal the throttle sensor also rotates and sends a voltage to the ECU. The ECU is programmed to interpret this voltage to a specific engine RPM. The ECU then increases voltage to the throttle body which opens the throttle valve until an engine speed is reached that is preprogrammed to correspond to the voltage output of the throttle sensor. The ECU will vary the voltage to the throttle body to open or close the throttle valve, depending on the throttle sensor position and engine load, to maintain the selected speed.

STRUCTURE AND FUNCTION 4. Throttle and Governor Operation: Upon engine cranking the ECU will automatically set the throttle valve to a predetermined position for best engine starting.

NOTE: there is no need to depress the accelerator pedal at start-up.

When the engine starts the ECU automatically opens the throttle valve to allow the engine to reach 1200 RPMs. The ECU monitors engine temperature and will set a fast idle if the engine is cold. There is a gradual return to base idle of 700 RPM as the engine temperature increases. After the short startup routine, the operator can operate the lift truck normally.

This sub-system also incorporates a RPM governing feature. The ECU will limit maximum engine RPM to 2700 regardless of the foot pedal position and load. If the engine RPM exceeds the maximum preprogrammed RPM of 3100 for an excess of 2 seconds the ECU will close the fuel lock-off valve which will shut the engine off. This is a safety feature to protect the engine and is called over speed protection.

5. Operating Specifications 4G63 / 4G64 Engines: Idle speed (Cold Engine) 700 – 1200 RPM based on engine temperature Idle speed (Warm Engine) 700 RPM Max governed speed (no load) 2700 RPM Ignition timing 10° BTDC Over speed protection Yes Condition 3100 RPM for more than 2 sec.

Result Close fuel lock-off. Engine shut down.

Over temperature protection Yes Condition Above 105 deg. C Result Check engine light flashes Condition Above 115 deg. C Result Limp home mode Max. engine speed reduced to 1200 RPM and engine is shut down if operated in excess of 45 seconds while temperature remains in excess of 115 deg. C Fuel lock-off protection

Only open when ECU detects an engine RPM.

Closed loop fuel control Condition Result

Yes A/F ratio out of spec.

Check engine light illuminated and LIMP Home mode and max speed is reduced to 1800 RPM.

50

System Adjustments: 1. Diagnostic Kit Installation This system requires that the service technician have available a diagnostic device. Two diagnostic tools are available. A laptop computer with a diagnostic kit or hand held diagnostic unit are available to troubleshoot the system.

Note: This service manual will reference the Laptop diagnostic kit for troubleshooting.

The Hand Held unit will provide the same information as a laptop with the diagnostic kit. The Hand Held unit however, requires the selection of each screen individually whereas the Laptop will show all the information on one screen.

Refer to the instructions that are included with these tools for information on their use.

Diagnostic kit for Laptop Computer part #93060-06300 Hand Held Diagnostic unit part #93060-06400 This software is designed to provide diagnostic information from lift trucks equipped with the S-15G industrial engine management systems.

It is to be used with a Windows compatible PC.

SYSTEM ADJUSTMENTS 6. Select "File" in the upper left screen.

7. Select the "Comport" option and select the "Com 1" Note: After installation and before using the laptop for diagnostics use, ensure that the COM1 port is selected for use with this software.

When utilizing these diagnostic tools you will be able to access information on the following system functions. Note: Only functions frequently used to troubleshoot will be detailed fully. Refer to the instructions that are included with each of the diagnostic tools for more information. General operating specifications are included with each parameter. These values can vary from the nominal values due to variation in local atmospheric conditions, fuel quality, age of truck, hours of use, and method of operations. Values that do not fall within the ranges specified do not necessarily indicate a malfunction. Rather, these values can be used to identify operating parameters that fall outside of the average range and used to investigate or to identify a possible operational problem.

System Requirements: Pentium I or greater Windows 95, 98 or NT 16 MB memory Disk space: 86 KB

Note: These adjustments require the use of an MCFA diagnostic tool. The following instructions reflect the use of a Laptop computer with Windows based diagnostic software.

Software Installation: Insert the Diagnostic installation disk into the drive.

1. Click on START, RUN and browse to a:\Setup.exe 2. Click on OPEN. 3. Click on OK 4. Follow installation instructions displayed on screen 5. Once installation is complete, start the diagnostic software and on the S-15G screen by double clicking on the "MCFA Diag" icon on the desktop screen.

2. Adjustments: The majority of system functions and operating parameters are pre-programmed and not able to be routinely altered by service technicians.

There are several adjustments which can be made if necessary, as follows: • Idle mixture. The mixers are preset at the factory and it is not expected that routine re-adjustment will be needed in the field. Following factory adjustment, a cap is installed over the idle mixture adjustment screw to prevent tampering.

In the event a mixer is replaced or the tamper resistant cap has been removed, 51

SYSTEM ADJUSTMENTS the adjustment procedure is as follows: Connect diagnostic monitor to data port located below the rubber plug on the ECU. Start engine and allow the engine to warm-up to operating temperature.

Once engine is fully warmed-up, depress the throttle pedal to allow the engine RPM to reach an excess of 2000 RPM for at least 2 seconds.

Release throttle, fully and allow RPM to decrease to a stable idle speed. When viewing the Laptop diagnostic monitor, the parameter "DWELL" is used to adjust the idle mixture. At idle the DWELL should be adjusted to 40-50%.

This adjustment is made by turning the idle mixture screw clockwise or counter clockwise, as necessary. NOTE: During actual operation, this value can vary from the initial set point due to changes in the atmospheric conditions and fuel quality.

Therefore, if at a later date the DWELL has changed, but is still with in a 20 – 80 range and performance is acceptable, re-adjustment is not necessary.

Install tamper-resistant cap over the idle mixture screw.

Remove diagnostic equipment and reinstall the rubber plug over the data port on the ECU.

ECU adjustment: 1. Connect diagnostic monitor to the data port located below the rubber plug on the ECU. 2. Turn the key switch to "ON" but do not start the engine.

3. At the top of the S-15G diagnostic screen, select Auto Pedal function.

4. Select Manual mode.

5. Enter 195 for the High and 45 for the Low. 6. Select "OK".

The ECU has now been reset to interface correctly with the signal provided by the throttle sensor.

• Throttle system: The ECU is preset at the factory and can not be adjusted. The ECU is programmed to use the signal from the throttle sensor to appropriately adjust the engine RPM. The throttle sensor has an operating range which is greater than the range used in this lift truck application and the ECU presets are set to reflect the proper range needed. The following procedure is to be followed if these settings have been tampered with:

• Throttle Sensor Adjustment: The throttle sensor converts the movement of the foot pedal by the operator into an electronic voltage that the ECU associates with an engine RPM. In order to interface correctly with the ECU presets, the throttle sensor and foot pedal must be adjusted so that the voltage output is within the range the ECU is set to. The following procedure is to be followed to ensure correct adjustment:

1.

2.

3.

4.

5.

6.

52

195

45

SYSTEM ADJUSTMENTS

1. Connect diagnostic monitor to the data port located below the rubber plug on the ECU. 2. Turn the key switch to "ON" but do not start the engine.

3. On the S-15G diagnostic screen, locate the "Pedal Angle" Note: The diagnostic monitor displays units rather than voltage. 0 units equal 0 volts. 255 units equal 5 volts 4. The value displayed should be between 28 to 45 units when the foot pedal is fully released. . ( One "unit" equals .0196 volts) If the value displayed is either below or above this value, adjustment is required. The potentiometer mounted to the throttle sensor has 2 set screws, loosen slightly to allow either clockwise or counter clockwise rotation depending on if the values are too high or too low.

Rotate the potentiometer to 35 +/- 5 units and use the data monitor screen to monitor the results. (Depending on specific truck model, throttle sensor removal from the mounting bracket may be necessary, but the electrical connection will remain connected) 5. Once rotated to the correct value, retighten the setscrews securing the potentiometer to the throttle sensor.

Reinstall the throttle sensor and the floor plate, if removal was required. This now completes the adjustment for the idle or minimum settings. The high idle or maximum setting will now be adjusted with floor plate installed.

Note: Do not apply excessive force to accelerator without floor plate installed. Damage to potentiometer may occur.

6. Fully depress the foot pedal with sufficient force to simulate actual use by an operator and apply pressure slowly.

While depressed fully note the voltage units value displayed on the diagnostic screen. The correct value should be 53

195 +/-5 units. If readjustment is necessary, loosen the locknut on the foot pedal stop bolt and adjust the height as necessary. Repeat this procedure until the correct foot pedal travel is attained to reach the desired value.

7. Once adjusted, re-tighten the locknut on the foot pedal stop bolt.

8. Remove diagnostic equipment and reinstall the rubber plug over the data port on the ECU.

SYSTEM ADJUSTMENTS 3. S-15G Screen Layout:

S-15G Screen Data Stream:

Length of Data Stream:

Must be scrolling if properly connected to ECU and key switch set to run position. If this value is not running (increasing in value) this indi cates the diagnostic cables are either not connected properly or no power is being supplied to the engine management system.

Typically 91 bytes

Analog Sensors: Pedal Angle Manifold Press.

Engine Temp.

Oxygen Volt.

Battery Volt.

0-255 Units (Typically range, 45-195 units) 36-38 kPa at no load idle to 100 kPa at full load governed speed Current value, in Deg C Displays oxy sensor voltage normal range 0.10 - .85 volt(s) Approximately 14.5v when charging

Running Parameters: Engine Speed Selected Speed Mode

Actuator Power LP Lockout Dashlight

Current value Design speed for system based on pedal position 0 Standby 1 Cranking 2 Idle 4 Normal 6 Over speed shutoff Throttle valve opening power 0-250 units 0 off, 1 on 0 off, 1 on (see "D" screen if 1 is displayed during running mode, check engine light should be displayed) 54

SYSTEM ADJUSTMENTS

3.1. Adjustments Detail: *Fuel T-Value Fuel table value *Fuel F-Value Final value after compensations *Throt. Rate Rate of change in MAP *Accel, Fast + for acceleration, - for deceleration Dwell Duty Cycle of Fuel Control Valve Solenoid, 0-100% *Oxy-Corr % of fuel adjustment due to the oxy sensor feedback *Oxy-Wait Count down timer before oxy feedback starts *On Time Comp.

Fast Acting Choke, depletes with revolutions completed * A non-adjustable preprogrammed value. Typically used only for MCFA engineering analysis.

Added Information on frequently reference parameters: Manifold Pressure: Engine manifold pressure (MAP) is an indicator of engine load. Higher loads result in numerically higher MAP value.

At idle the Manifold Pressure should be 35-45 kPa. At high idle (2700RPM) with the transmission engaged, the MAP should be 42-47 kPa. At torque converter stall (transmission engaged, brakes fully applied to prevent movement, and foot pedal fully depressed) the MAP should read about 80-100KPa for one to two seconds. If your readings are different than these, inspect the vacuum hose to be sure it is not disconnected from the ECU, the fitting on the throttle body, or damaged. There are two barbed fittings on the throttle body. The lower fitting provides the MAP signal to the ECU. The upper fitting should be connected to the distributor. If the hoses are all connected correctly and do not appear damaged, check the ignition timing. Correct timing is 10° BTDC. Engine Temp: This will vary with the temperature of the engine. If the diagnostic monitor displays either 0° or 127°C it may indicate the temperature sensor has been physically damaged, a electrical short circuit occurred, or the sensor has been disconnected.

Battery Volts: This is simply an indication of the Battery Voltage and will vary with the bat55

tery state of charge and alternator output.

When the engine is not running it should be close to 12 Volts. When the engine is running and there is an output from the Alternator you should see approximately 13-15 Volts depending on the battery's condition.

Actuator Power: This is the voltage signal the ECU sends to the Throttle Body Governor to energize the coils that controls the valve. At idle, it will read approximately 20-30 units, increasing with higher RPMs. At maximum load the output will be about 170-220 Units (Converter Stall Condition). NOTE: These values can vary significantly, but can be used to compare from one running condition to another and this trend of voltage change versus engine RPM and load can help during troubleshooting.

Dwell: This value is the amount of time the Fuel Control Solenoid Valve (FCSV) is activated and open to vacuum, by the ECU. The FCSV operates at specific "DWELL" based on fuel requirements. A 50% dwell means the valve is open 50% of the time and closed 50% of the time. A DWELL of 100% indicates that the valve is open 100% of the time and the fuel control system is at full "lean". A DWELL of 0% indicates that the valve is closed 100% of the time and the fuel control system is full "rich".

SYSTEM ADJUSTMENTS 3.2 Diagnostic Screen Layout: Diagnostic "D" Codes Screen

Data Stream: Length of Data Stream: Com Port: Program Version: Map Version: Check Engine Codes:

Must be scrolling for proper connection to ECU Typically 91 bytes Shows Com Port selected from pull-down menu Indicates EPROM installed in ECU Indicates ECU calibration NONE - No check engine codes BAT Battery Voltage Error CHRG - Charging System Error ETMP Engine Block Temperature Sensor Error HTMP - High Engine Block Temperature KILL Emergency Engine Shutdown Activated MAP Manifold Absolute Pressure signal Error OXY Oxygen Sensor Error/Fuel System Error THRPedal Sensor out of Range/Open Circuit TRIG TACH Signal Error

56

TROUBLESHOOTING

S-15G Fuel System Troubleshooting: Introduction: The majority of possible malfunctions can cause differing symptoms depending on the specific cause and frequency of occurrence. For example, an intermittent electrical short could sometimes prevent an engine from starting and at other times cause intermittent stalling or rough operation.

1. Trouble Shooting Detail: 1.1 Problem: Engine "turns over" when starter motor is engaged, but will not start.

Analysis: First, Check LPG tank and supply hoses and filters. Most often there are 2 reasons an engine will not start if there is fuel available. Either the malfunction is in the ignition system or the fuel supply system. Note: This manual is intended as a supplement to detail the engine management system. The ignition system and test methods are covered in more detail in the chassis service manual. Once it is established the ignition system is working properly, the fuel supply system will need to be evaluated. It needs to be determined if LPG fuel is being supplied to the engine. The following steps should be followed: 1) Connect the diagnostic monitor to the ECU and go to the "S" screen.

2) Turn the key to the "run" position, but do not engage the starter motor. The data stream should begin counting. If there is no Data Stream, check the data monitor cables for proper installation. If there is still no data stream, the engine management system may not be getting power. Check the electrical connections that supply power and ground to the engine management wiring harness. (See wiring harness schematic). If all the connections are intact, remove the connector from the ECU and use a Fluke 87, OTC 600, or equivalent meter to test for a 12V-power supply on pin #4 and for ground on pin 8.

57

3) If 12 volt power to pin 4 and/or ground connection to pin 8 is not indicated, use general electrical troubleshooting procedures to track down the cause.

(Reference the engine management wiring harness in the schematic section of this manual and the chassis wiring harness schematic in the chassis service manual.)

4) If the ground and power supply are working correctly, turn the key off and reconnect the ECU connector. View the data monitor while engaging the starter motor by moving the key to the start position for approximately 10 seconds.

5) While the starter motor is engaged and viewing the data monitor, check to see if a RPM is being displayed in Engine Speed indicator. If no RPM is being registered, this may signify a wiring problem between the distributor and the ECU on pin #1.

Investigate and repair. If no problem is found an ECU failure may have occurred.

Replace ECU. 6) If the RPM is being registered, check the lock off valve for proper function. The lock off will open only when the ECU detects a RPM during starting which is a method of reducing the chance of a LPG leak.

Disconnect the connector from the wiring harness to the lock off. Connect the electrical meter to the connector on the wiring harness and check for 12-volt power to the lock off when the starter motor is engaged and while the Data monitor is registering RPM. If no power is being supplied to the lock off during starting, inspect and repair the wiring harness. If no wiring problem is detected, an ECU failure may have occurred.Replace ECU 7) If power is being supplied to the lock off, but it is not opening properly, test LP lock off Solenoid coil for open circuit. Repair as needed.

TROUBLESHOOTING 1.2. Problem: Engine starts, but stalls immediately Analysis: If an engine starts, but runs poorly, the potential causes are listed below: Note: * please refer to the Chassis service manual for further explanation.

• LPG regulator converter malfunction. If defective replace entire regulator assembly.

No kit is available.

• Mixer malfunctions. Check and clean. If defective replace entire mixer assembly.

No kit is available.

• Leaks in LPG supply lines.

• Operating temperatures below -20° F resulting in cold LPG tanks which can result in low tank pressures.

• * Ignition system malfunctions.

• Fuel supply restricted or cut off.

• * Engine in questionable condition.

1.3. Problem: Rough unstable idle. Poor acceleration. High engine idle.

Analysis: A rough or unstable idle can have many potential causes. The first step at diagnosis is to perform the following inspections: Note: * please refer to the Chassis service manual for further explanation.

• Inspect the vacuum lines: (see vacuum hose diagram) • mixer to the FCSV • throttle body to the distributor • throttle body to the ECU. • * Check air filter and clean or replace.

• Check LPG filter.

• * Vacuum leaks in the intake system.

• Engine block temperature sensor. The sensor should be registering a temp of approximately 65 ° to 90° C depending on ambient conditions, length of time running and load used. Generally speaking, the temperature displayed should increase appropriately following initial startup and this indicates proper operation.

• * Ignition system and timing check. Inspect for proper operation.

• Inspect and clean the check valve in the balance line. (See vacuum hose diagram).

58

•

This check valve is intended to move freely in the housing. If the ball seems to be stuck or not moving freely, clean with an oil and residue free automotive type cleaner.

For a high engine idle see all comments above. Also, check to ensure the min and max values in the ECU and throttle sensor are adjusted properly. On cushion type models check throttle cable as a minimum of only 1/8 inch slack.

TROUBLESHOOTING 1.4. Problem: The check engine light comes on intermittently while the engine is allowed to idle for extended periods of time.

Analysis: Some trucks in the field can occasionally have this happen. In the event this problem occurs and also is accompanied by a "buzzing" noise coming from the mixer.

This "buzzing" can be corrected by adjusting the "minimum" limit set screw on the throttle body.

1) Remove the throttle body from the intake manifold.

2) Locate the correct setscrew. (see diagram for location of setscrew) 3) Turn the screw counter clockwise 1 turn.

4) Reinstall the throttle body and check for operation.

5) If not corrected repeat the same procedure as above and rotate the setscrew an additional HALF turn counterclockwise.

6) If problem is not corrected contact your local Authorized Caterpillar dealer for further assistance.

59

TROUBLESHOOTING

Rough/Unstable Idle

Engine does not start / Fuel

2. Trouble shooting Tree Detail No LP-gas in tank.

Refill LP-gas tank.

Improper operating procedure.

Check outlet valve on LP-gas tank is open.

Do not press accelerator pedal with start up.

Is LP-gas is supplied to convertor?

Check yellow/blue wire (Pin #4) to battery positive with key switch on.

No power, repair open wire or replace wire harness.

Does Fuel Lock Off have power?

Check for 12volt power with engine cranking over.

No power, Repair open wire or replace wire harness.

Wires OK, Replace ECU

Check for Spark.

Check Battery Check Spark Plug Gap. Inspect Coil Wire Harness.

Distributor Pickup.

Check Mechanical Conditions.

Check Engine Condition (Mechanical).

Check Fuel System (Mechanical).

Check Vacuum Hoses.

See Vacuum hose diagram for routing.

Check Engine Block Temp Sensor.

If disconnected the reading will be 127 degree C on the diagnostic screen.

Check Oxygen Sensor.

Check connection.

Check Ignition System.

Check spark plug connections and condition.

Test primary and secondary Ignition systems.

Check Fuel level

Check LP-gas tank level.

60

Poor Acceleration

TROUBLESHOOTING

Is engine getting Air?

Check Air Filter

Check Map Sensor Vacuum hose.

Is hose disconnected, pinched or plugged?

Map Sensor should read 35-45 kpa at idle.

Map Sensor does not change Replace ECU with raise of rpm,

Connect Diagnostics & Check For Codes

Pedal Sensor Adjustment Dwell

O2 Voltage

High Engine Idle

Map

Clean or Replace.

Select RPMS (2700) Pedal units (195) Idle?

Full RPM? Stall?

Idle?

Full RPM? Stall?

Idle?

Full RPM? Stall?

Check Valve Test (Balance Line) Ball.

Ball must move freely and be free of oil.

Clean or Replace.

Ignition Timing.

Actual Misfire

Check Pedal Position Adjustment.

See Pedal Position Adjustment section.

Check Ignition Timing.

Engine Timing 10˚ BTDC.

Check for Intake manifold or Throttle Body gasket leaks.

Spray suspected area with WD40, the engine will suck into the combustion chamber and the engine rpm raise.

Retorque bolts.

61

TROUBLESHOOTING 3. Check Engine Light Blink Faults Blink Codes: a series of regular flashes of the Check Engine Light. These maybe diagnostic codes or warning codes.

Warning codes occur while the engine is running.

Diagnostic codes are displayed when the engine RPM is "0" and the key is in the "run" position.

When the key switch is turned on, the Check Engine Light is illuminated to show that the lamp is operational. If the engine is not started, the light will turn off after 20 seconds. If error codes are detected (RPM=0), the light will begin to blink codes sequentially after an additional 15 seconds.

Condition

Lamp Status

Indication

RPM=0 RPM=0 RPM>0 RPM>0 RPM>0 RPM>0

Lamp off after 30 seconds After 45 seconds, Lamp flashes Lamp off Lamp blinks slowly Lamp blinks quickly Lamp on steady

No error codes Shows error codes Normal operation Charging system problem Overheat / Over speed Other error detected

4. System Fault Codes After 45 seconds in standby mode, the Check Engine Light will blink to display any known faults.

The light will blink in one second intervals to indicate the following errors. In the case of multiple codes, there will be a five second pause between code sequence.

Number of Flashes 3 4 6 8 9

Fault Indication Fuel System error Pedal Sensor open Engine Temperature Sensor Battery Voltage TACH. (RPM input)

Note: These codes will also be displayed on the handheld monitor or laptop display if an error is apparent during normal operation.

62

TROUBLESHOOTING 5. Effects of Fault Conditions Note: The ECU does not store fault codes, at restart the system will cycle through self test and energize the Check Engine Light if a fault condition remains.

Code acronym displayed on diagnostic screen of handset or PC. Voltage Error: BAT (8 flashes)

ECU Function: The ECU checks the charging circuit for alternator output voltage. If voltage is below 12 volts the Check Engine Light will illuminate. If charging voltage returns to specification the light will turn off after the next successful test.

Effects on Operation: No immediate change to operation, governor performance may suffer.

Voltage Error: CHRG (0 flashes)

ECU Function: The ECU checks the charging circuit for alternator output voltage. If voltage is above 15.5 volts the Check Engine Light will illuminate. If charging voltage returns to specification the light will turn off after the next successful test.

Effects on Operation: No immediate change to operation, governor performance may suffer.

Engine Temp Sensor: ETEMP (6 flashes)

ECU Function: ECU will display 127° C. on diagnostic display. The Check engine Light will flash.

Effects on Operation: No cold engine operation or fuel compensation. Loss of cold engine operation.

Possible Cause: Faulty sensor or open/shorted wiring problem.

Temp Error: HTEMP (6 flashes)

ECU function: Over 105° C. Check Engine Light flashes.

Over 115° C. engine enters limp home mode, engine RPM reduced to 1200 RPM. Engine shut down occurs after 45 seconds.

After engine restart, system will not check for over temperature for another 45 seconds.

Effects on Operation: Engine RPM is reduced to 1200 RPM, engine shut down occurs 45 seconds later.

63

TROUBLESHOOTING Oxygen Sensor: OXY (3 flashes)

ECU Function: Oxygen sensor voltage 0.1 volts to 0.85 volts out of range, Check Engine Light is illuminated.

Effects on Operation: Engine enters Limp Home Mode, Check Engine Light is illuminated.

Maximum engine speed is reduced to 1800 RPM.

Fly Wheel Sensor: TRIG (9 flashes)

ECU Function: ECU does not see engine TACH signal. Open wire to ECU. Effect on Operation: Fuel lock of will not function. Engine will not operate without TACH. signal.

64

65

-

-

-

A B C

D E F G

H I

LP VAPORIZER/ REGULATOR

LIQUID PROPANE IN

B C

G

FILTERED INTAKE AIR

F

FUEL CONTROL SOLENOID VALVE HIGH PRESSURE LP REGULATED PROPANE GAS ATMOSPHERIC PRESSURE COMPENSATION CONTROL SIGNAL VACUUM CHAMBER DIAPHRAGM RESTRICTOR CHECK VALVE FUEL CONTROL SOLENOID VALVE AIR/GAS MIXER DIAPHRAGM/METERING VALVE

A

D

E

GASEOUS PROPANE OUT

I

TO THROTTLE BODY

AIR / GAS MIXER

H

SCHEMATICS

1. CARB 1 Tier 1 LP Fuel Vacuum System Diagram

ECU Connector as seen from Harness side

66 GREY

WHITE

BLACK/WHITE

GREEN

ORANGE

BROWN

RED

WHITE

FCSV

GROUND

ACCELERATOR SENSOR

OXYGEN SENSOR

DISPLAY CONNECTOR

PURPLE

BLACK

BLACK

KEY SWITCH

BLUE/YELLOW

CHECK ENGINE LIGHT

RED RED RED

YELLOW/GREEN

GROUND

BLACK

CARBURETOR THROTTLE BODY

15 AMP FUSE IN CONSOLE

BLACK/RED

BLACK

RED

BLACK

FUEL LOCK OFF

YELLOW/BLUE

BLUE/BLACK BLACK RED

GREEN/BLACK

S15G SYSTEM

TO BATTERY +

THERMAL RESISTOR AT ENGINE BLOCK

BLACK

BLUE

COIL

SCHEMATICS 2. CARB 1 Tier 1 Wiring Schematic

SCHEMATICS 3. CARB 1 TIER 1 ECU Pin Location Pin #

Color

Function

1

Red(R)

TACH Signal (To coil NEG)

2

Yellow/Green (Y/G)

Console System Fault Light (Check Engine Light NEG)

3

Green (G)

Throttle Pedal Sensor (0.3-4.7 volt input to ECU)

4

Yellow /Blue (Y/L)

Battery Power (Key switched-Fused)

5

White (W)

Oxygen Sensor (Signal to ECU)

6

Green/Black (G/B)

(NEG connection to ECU) LPG Lock Off

7

White (G)

Fuel Control Solenoid Valve (NEG connection to ECU)

8

Black (B)

Battery NEG to truck frame

9

Orange (OR)

Pedal Angle Sensor (5 volt source from ECU)

10

Black/White (B/W)

Pedal Sensor Filtered Ground (NEG connection to ECU)

11

Brown (Br)

Engine Temperature Sensor (Signal to ECU)

12

Blue/Black (L/B)

Throttle Body Governor Signal (Variable voltage output from ECU)

67

ECU Connector as seen from Harness side

GREEN/BLACK

COIL

BLACK

CARBURETOR THROTTLE BODY

BLACK

RED

RED RED RED

BLUE/BLACK BLACK RED BLACK BLACK/RED

BLUE

GROUND BLUE/YELLOW

66

15 AMP FUSE IN CONSOLE

YELLOW/BLUE YELLOW/GREEN FCSV

PURPLE

KEY SWITCH

BLACK

TO BATTERY +

CHECK ENGINE LIGHT

DISPLAY CONNECTOR

WHITE

RED

WHITE

GREY

BROWN

OXYGEN SENSOR

GROUND

ORANGE

BLACK

GREEN

BLACK/WHITE

THERMAL RESISTOR AT ENGINE BLOCK

ACCELERATOR SENSOR BLACK

SCHEMATICS

FUEL LOCK OFF

2. CARB 1 Tier 1 Wiring Schematic

S15G SYSTEM

SCHEMATICS 3. CARB 1 TIER 1 ECU Pin Location Pin #

Color

Function

1

Red(R)

TACH Signal (To coil NEG)

2

Yellow/Green (Y/G)

Console System Fault Light (Check Engine Light NEG)

3

Green (G)

Throttle Pedal Sensor (0.3-4.7 volt input to ECU)

4

Yellow /Blue (Y/L)

Battery Power (Key switched-Fused)

5

White (W)

Oxygen Sensor (Signal to ECU)

6

Green/Black (G/B)

(NEG connection to ECU) LPG Lock Off

7

White (G)

Fuel Control Solenoid Valve (NEG connection to ECU)

8

Black (B)

Battery NEG to truck frame

9

Orange (OR)

Pedal Angle Sensor (5 volt source from ECU)

10

Black/White (B/W)

Pedal Sensor Filtered Ground (NEG connection to ECU)

11

Brown (Br)

Engine Temperature Sensor (Signal to ECU)

12

Blue/Black (L/B)

Throttle Body Governor Signal (Variable voltage output from ECU)

67

INSPECTION AND ADJUSTMENT

Converter (Vaporizer)

LP-gas carburetor Low-pressure hoses (gas hoses) Hot-water hoses Engine

Every 4800 service hours or 2 years

LP-gas filter

Every 2400 service hours or 1 year

High-pressure hoses

Every 1200 service hours or 6 months

LP-gas tank and bracket

● ● ● ●

● ● ● ●

●

● ●

● ●

● ● ● ● ● ● ●

●

● ● ●

● ● ●

● ● ●

●

● ●

● ●

● ●

● ● ● ● ●

● ● ● ● ● ● ●

● ● ● ● ● ● ●

● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●

Every 10 service hours or daily (pre-start)

item

Every 200 service hours or monthly

1. Periodic inspection schedule

service

Check bracket for installation.

Check bands for tightness.

Check valves and gauge for leaks.

Check hoses and fittings for damage.

Replace hoses.

Check for installation.

Check fuel lines for leaks.

Replace kit parts.

Replace Assembly (S-15G System) Remove tar.

Check connectors for tightness.

Check fuel lines for leaks.

Replace kit parts.

Check for installation.

Check fuel lines for leaks.

Replace kit parts.

Check for installation.

Check bands for tightness.

Check for damage.

Check bands for tightness.

Idling and acceleration CO measurement Check Faults and Codes

68

● ● ●

ELECTRICAL SYSTEM SCHEMATIC (GASOLINE MODELS) Torqueconverter oil temperature warning lamp

Air cleaner Brake fluid Engine oil pres. Alternator not LPG pressure warning lamp level warning warning lamp charging warn- warning lamp (option) lamp ing lamp (option)

Radiator coolant level warning lamp (option)

ELECTRICAL SYSTEM GASOLINE MODELS (ENGINE GROUP)

(5) Wire color codes are in accordance with JIS. (4) Terminal arrangement of connector shown by mark must be instrumental arrangement.

(3) Circuit shown by chain double-dashed line () must be optional circuit.

(2) Circuit shown by dashed line () must be 2 speed T/M controller circuit.

Notes (1) Unless otherwise specified, wire size must be 1.25mm2 206774

47

ELECTRICAL SYSTEM SCHEMATIC (DIESEL MODELS) Torqueconverter oil temperature warning lamp

Brake fluid Air cleaner Engine oil pres, warning lamp level warning warning lamp lamp (option)

Alternator not Glow lamp Fuel filter drain charging warnwarning lamp ing lamp

Radiator coolant level warning lamp (option)

ELECTRICAL SYSTEM

(5) Wire color codes are in accordance with JIS. (4) Terminal arrangement of connector shown by mark must be instrumental arrangement.

(3) Circuit shown by chain double-dashed line () must be optional circuit.

(2) Circuit shown by dashed line () must be 2 speed T/M controller circuit.

Notes (1) Unless otherwise specified, wire size must be 1.25mm2 206775

49

®

Lift Trucks

Service Manual GM 4.3L, G6 Gasoline Engine 003103-up

For use with the GC35K-GC70K; GP40-GP50; GP40K-GP50K Chassis Service Manuals.

99789-84120

FOREWORD This service manual covers the GM 4.3L Gasoline Engine installed in CAT® Lift Trucks and gives detailed maintenance and repair information. For your convenience the instructions are grouped by systems as a ready reference.

The long productive life of your lift truck(s) depends on regular and proper servicing. Servicing consistent with what you will learn from this service manual. Read the respective sections of this manual carefully and familiarize yourself with all the components before attempting to start a test, repair or rebuild job.

The descriptions, illustrations and specifications contained in this manual are for engines with serial numbers in effect at the time of printing. CAT Lift Trucks reserves the right to change specifications or design without notice and without incurring obligation.

Whenever a question arises regarding this engine, or this manual, consult your Cat lift truck dealer for the latest available information.

For items pertaining to the chassis, refer to the Chassis Service Manual. This service manual covers the fuel system for units built before 01/01/2004. See fuel system supplements for units built after 01/01/2004.

Notes, Cautions, and Warnings NOTES, CAUTIONS, and WARNINGS are used in this manual to emphasize important and critical instructions. They are used for the following conditions:

NOTE

To highlight an essential operating procedure or condition.

! CAUTION

!

Operating procedures or practices that will result in damage to or destruction of the engine if not strictly observed.

WARNING

Operating procedures or practices that will result in serious injury or loss of life if not correctly followed.

-I-

How to Read This Manual Scope of Explanation This book describes the service procedures for the engine removed from a vehicle.

For procedures concerning the removal of the engine from the vehicle and on-vehicle inspection and servicing, refer to the appropriate service manuals separately prepared for the individual models.

Maintenance and Servicing Procedures (1) A diagram of the component parts is provided near the front of each section in order to give the reader a better understanding of the installed condition of component parts.

(2) The numbers provided within the diagram indicate the sequence for maintenance and servicing procedures; the symbol N indicates a non- reusable part; the tightening torque is provided wher e applicable.

• Removal Steps: The part designation number corresponds to the number in the illustration to indicate removal steps.

• Installation Steps: Specified in case installation is impossible in reverse order of removal steps. Omitted if installation is possible in reverse order of removal steps.

• Disassembly Steps: The part designation number corresponds to the number in the illustration to indicate disassembly steps.

• Reassembly Steps: Specified in case reassembly is impossible in reverse order of disassembly steps. Omitted if reassembly is possible in reverse order of disassembly steps.

Classification of Major Maintenance/Service Points When there are major points relative to maintenance and servicing procedures (such as essential maintenance and service points, maintenance and service standard values, information regarding the use of special tools, etc.), these are arranged together as major maintenance and service points and explained in detail.

A

Indicates there are essential points for removal or disassembly.

B

Indicates there are essential points for installation or reassembly.

Symbols for Lubrication, Sealants and Adhesives Information concerning the locations for lubrication and application of sealants and adhesives is provided, by using symbols, in the diagram of component parts, or on the page following the component parts page, and explained.

Grease (multi-purpose grease unless there is a brand or type specified) Sealant or adhesive Brake fluid, automatic transmission fluid or air conditioner compressor oil Engine oil or gear oil

Inspecting Only the inspections to be performed by using special tools or measuring instruments are covered. General service procedures not covered in this manual, such as visual inspections and cleaning of parts should always be performed during actual service operations.

-II-

Removal and Installation

➧A ➧

Removal steps 1. Plug 2. Nut 3. Bolt 4. Pan 5. Gasket 6. Bolt 7. Pin 8. Pump 9. Retainer 10. Shaft 11. Bolt 12. Pin 13. Cover 14. Screen

Unit: kgf-m (lb-ft) [N-m] *kgf-m (lb-in.) [N-m] 15.

16.

17.

18.

19.

20.

21.

22.

23.

24.

25.

Plug Valve Spring Filter Fitting Valve Bolt Adapter - Oil Filter Gasket Connector Gasket

23

N

22

N

25 20 19

24 T = 2.08 (15) [20]

Denotes nonreusable part.

21

18

10

9 Lubricate all internal parts with engine oil during

7

8 T = 9.14 (66) [90]

6 17

14

16 15

13

INSTALLATION OR REMOVAL SERVICE POINTS

➧A ➧ Install the oil pump screen.

12 T = 1.22 (106) [12]

• If removed, replace the oil pump screen. The oil pump screen must have a good press fit into the oil pump body.

• Mount the oil pump in a soft jawed vise.

• Apply sealer to the end of the pipe.

• Use the (J 21882) and a soft-faced hammer to tap the oil pump screen into the pump body. The screen must align parallel with the bottom of the oil pan when it is installed.

11 5

N

Denotes tightening torque.

4 1

2 3

T = 2.49 (18) [25]

T = 2.49 (18) [25]

J 21882

Operating procedures, cautions, etc., on removal, installation, disassembly and reassembly are described.

This alphabetical letter corresponds to a part that is indentified in the drawing on the first page of each section. The letter appears during an explanation of removal, installation, disassembly or reassembly steps.

-III-

T = 2.49 (18) [25]

!

WARNING

!

The OPERATION & MAINTENANCE MANUAL outlines the proper and safe lubrication and maintenance for the truck, as recommended by Cat Lift Trucks.

WARNING

Do not operate this truck unless you have read and understand the instructions in the OPERATOR’S MANUAL. Improper truck operation is dangerous and could result in injury or death.

Read and understand the OPERATION & MAINTENANCE MANUAL before performing any lubrication or maintenance. Improperly performed lubrication or maintenance procedures are dangerous and could result in injury or death.

5. Use steps and grab handles (if applicable) when mounting or dismounting a truck. Clean any mud or debris from steps, walkways or work platforms before using. Always face truck when using steps, ladders and walkways. When it is not possible to use the designed access system, use ladders, scaffolds, or work platforms to perform safe repair operations.

6. To reduce the risk of back injury, use hoist when lifting components which weigh 23 kg (50 lb.) or more. Make sure all chains, hooks, slings, etc., are in good condition and are of the correct capacity. Be sure hooks are positioned correctly. Lifting eyes are not to be side loaded during a lifting operation.

7. To reduce the risk of burns, be alert for hot parts on trucks which have just been stopped and have hot fluids in lines, tubes and compartments.

8. Be careful when removing cover plates.

Gradually back off the last two bolts or nuts located at opposite ends of the cover or device and pry cover loose to relieve any spring or other pressure before completely removing the last two bolts or nuts.

9. Be careful when removing filler caps, breather and plugs on the truck. Hold a rag over the cap or plug to prevent being sprayed or splashed by liquids under pressure. The danger is even greater if the truck has just been stopped because fluids can be hot.

10. Always use tools that are in good condition and understand how to correctly use them before performing any service work.

11. Reinstall all fasteners with same part number.

Do not use a lesser quality fastener if replacements are necessary. Do not mix metric fasteners with standard nuts and bolts.

12. If possible, make all repairs with the truck parked on a level, hard surface. Block the truck so it does not roll while working on or under it.

13. Disconnect battery and discharge any capacitors (electric trucks) before starting to work on the truck. Hang “Do Not Operate” tag in the Operator’s Compartment.

Because the service mechanic may be unfamiliar with many of the systems on this truck it is important to use caution when performing service work. Knowledge of the system and/or components is important before the removal or disassembly of any component.

Because of the size of some of the truck components, the service mechanic should check the weights noted in this Manual. Use proper lifting procedures when removing any components.

Following is a list of basic precautions, cautions and notices that should always be observed.

1. Read and understand all warning plates and decals on the truck before operating, lubricating or repairing the part or system.

2. Always wear protective glasses and protective shoes when working around trucks. In particular, wear protective glasses when pounding on any part of the truck or its attachments with a hammer or sledge. Use welder's gloves, hood/goggles, apron and other protective clothing appropriate to the welding job being performed. Do not wear loose-fitting or torn clothing. Remove all rings from fingers when working on truck.

3. Do not work on any truck that is supported only by lift jacks or a hoist. Always use blocks or jack stands to support the truck before performing any disassembly.

4. Lower the forks or other implements to the ground before performing any work on the truck.

If this cannot be done, make sure the forks or other implements are blocked correctly to prevent them from dropping unexpectedly.

-IV-

!

WARNING

14. Repairs which require welding should be performed only with the benefit of the appropriate reference information and by personnel adequately trained and knowledgeable in welding procedures.

Determine the type of metal being welded and select correct welding procedure and electrodes, rods or wire to provide a weld metal strength equivalent at least to that of parent metal.

15. Do not damage wiring during removal operations. Do not reinstall damaged wiring.

Reinstall the wiring so it will not be damaged in operation by contacting sharp corners, or by rubbing against an object or hot surface. Do not connect wiring to a line containing fluid.

16. Be sure all protective devices, including guards and shields, are properly installed and functioning correctly before starting a repair. If a guard or shield must be removed to perform the repair work, use extra caution.

17. When the mast needs to be in the raised position during maintenance and repairs, always support the mast and carriage to keep the carriage or attachments raised.

18. Loose or damaged fuel, lubricant and hydraulic lines, or tubes and hoses can cause fires. Do not bend or strike high pressure lines or install ones that are bent or damaged. Inspect lines, tubes and hoses carefully. Do not check for leaks with your hands. Pin hole (very small) leaks can result in a high velocity oil stream that will be invisible upon close inspection of the hose. This oil can penetrate the skin and cause serious injury. Use cardboard or paper to locate pin hole leaks.

19. Tighten connections to the correct torque.

Make sure all heat shields, clamps and guards are installed correctly to avoid excessive heat, vibration or rubbing against other parts during operation. Shields must be correctly installed if they protect against oil spray onto hot exhaust components in the event of a line, tube, or seal failure.

20. Relieve all pressure in air, oil or water systems before any lines, fittings or related items are disconnected or removed. Always make sure all raised components are blocked correctly. Be alert for possible pressure when disconnecting any device from a system that uses pressure.

21. Do not operate a truck if any rotating part is damaged or contacts any other part during operation. Any high speed rotating component that has been damaged or altered should be checked for balance before reusing.

!

WARNING

22. Caution should be used to avoid breathing dust that may be generated when handling components containing asbestos fibers. If this dust is inhaled, it can be hazardous to your health.

If dust containing asbestos is present, there are several common sense guidelines that should be followed. a. Never use compressed air for cleaning. b. Avoid brushing or grinding asbestos containing materials. c. For clean up, use wet methods or a vacuum equipped with a high efficiency particulate air (HEPA) filter. d. Use exhaust ventilation on permanent machining jobs. e Wear an approved respirator if there is no other way to control the dust. f. Comply with applicable rules and regulations for the work place. g. Follow environmental rules and regulations for disposal of asbestos. h. Avoid areas where asbestos particles may be in the air.

-V-

Precautions

• • • •

Precautions for Disassembly and Assembly This section contains basic safety precautions and outlines basic recommended procedures, some of which require special tools, devices or work methods.

However, the safety precautions contained herein are not for all service work. It is the responsibility of service personnel to know that specific requirements, precautions and work hazards exist and to discuss these with a foreman or supervisor.

Replacing Engine Gaskets Gasket Reuse and Applying Sealant • Do not reuse any gasket unless specified.

• Gaskets that can be reused will be identified in the service procedure.

• Do not apply sealant to any gasket or sealing surface unless specified in the service procedure.

Separating Components • Use a rubber mallet in order to separate the components.

• Bump the part sideways in order to loosen the components.

• Bumping of the component should be done at bends or reinforced areas of the component to prevent distortion of the components.

Cleaning Gasket Surfaces • Use care to avoid gouging or scraping the sealing surfaces.

• Use a plastic or wood scraper in order to remove all the sealant from the components.

• Do not use any other method or technique to remove the sealant or the gasket material from a part.

• Do not use abrasive pads, sand paper or power tools to clean the gasket surfaces.

• These methods of cleaning can cause damage to the component sealing surfaces.

• Abrasive pads also produce a fine grit that the oil filter cannot remove from the engine oil.

This fine grit is abrasive and can cause internal engine damage.

Disassembly 1. Always use tools that are in good condition.

Understand how to use them before performing any service work.

2. Use an overhaul stand or a work bench, if necessary. Also, use bins to keep engine parts in order of removal.

3. Lay down the disassembled and cleaned parts in the order in which they were removed to save time for assembly.

4. Pay attention to marks on assemblies, components and parts for their positions or directions. If necessary, add marks to aid in assembly.

5. During removal or cleaning, carefully check each part for any sign of faulty condition. Signs of wear or abnormalities that caused the engine to work abnormally are more easily and accurately spotted during removal or cleaning.

6. Get help when lifting or carrying a part that is too heavy or awkward for one person to handle.

If necessary, use a jack or a hoist.

Separating Parts Important: Many internal engine components will develop specific wear patterns on their friction surfaces.

When disassembling the engine, internal components MUST be separated, marked and organized in a way to ensure reinstallation to the original location and position.

Mark or identify the following components: • Piston and the piston pin • Piston to the specific cylinder bore • Piston rings to the specific cylinder bore • Connecting rod to the crankshaft journal • Connecting rod to connecting rod cap • Crankshaft bearings and connecting rod bearings • Engine camshaft and valve lifters • Valve lifters, valve rocker arms and valve rocker arm supports

Valve to valve guide Valve spring to cylinder head location Engine block bearing cap location and direction Oil pump drive and driven gears

Service Prior to Assembly • Dirt will cause premature wear of the rebuilt engine. Clean all the component.

• Use the proper tools to measure the components when checking for excessive wear.

Components not within the manufacturer’s specification must be repaired or replaced.

• When the components are re-installed into an engine, return the components to the original location, position and direction.

• During assembly, lubricate all the moving parts with clean engine oil (unless otherwise specified).

The engine oil will provide the initial lubrication when the engine is first started.

-VI-

Tools and Equipment

Assembling Components • Assemble components using only the sealant (or equivalent) that is specified in the service procedure.

• Sealing surfaces must be clean and free of debris or oil.

• Specific components such as crankshaft oil seals or valve stem oil seals may require lubrication during assembly.

• Components requiring lubrication will be identified in the service procedure.

• Apply only the amount of sealant specified in the service procedure to a component.

• Do not allow the sealant to enter into any blind threaded holes, as the sealant may prevent the fastener from clamping properly or cause component damage when tightened.

• Tighten fasteners to the proper specifications.

DO NOT overtighten the fasteners.

Special tools are listed and illustrated throughout this manual. The tools (or equivalents) are specially designed to quickly and safely accomplish the operations for which the tools are intended. The use of special tools will also minimize possible damage to engine components. Some precision measuring tools are required for inspection of certain critical components. Torque wrenches and a torque angle meter are necessary for the proper tightening of various fasteners.

To properly service the engine assembly, the following items should be readily available: • Approved eye protection and safety gloves • A clean, well-lit, work area • A suitable parts cleaning tank • A compressed air supply • Trays or storage containers to keep parts and fasteners organized • An adequate set of hand tools • Approved engine repair stand • An approved engine lifting device that will adequately support the weight of the components

Assembly Cleanliness and Care This engine is a combination of many machined, honed, polished and lapped surfaces with tolerances that are measured in ten thousandths of an inch. Care and cleanliness are important when any internal engine parts are serviced. During assembly, a liberal coating of engine oil should be applied to friction areas to protect and lubricate the surfaces on initial operation. Throughout this section, it should be understood that proper cleaning and protection of truck surfaces and friction areas are part of the repair procedure. This is considered standard shop practice, even if not specifically stated.

When valve train components are removed for service, they should be retained in order. At the time of installation, they should be installed in the same locations and with the same mating surface as when removed.

1. Wash all parts, except for oil seals, O-rings, rubber sheets, etc., with cleaning solvent and dry them with air pressure.

2. Always use tools that are in good condition and be sure you understand how to use them before performing any service work.

3. Use only good-quality lubricants. Be sure to apply a coat of oil, grease or sealant to parts as specified.

4. Be sure to use a torque wrench to tighten parts for which torques are specified.

5. Replace gaskets and packings with new ones.

-VII-

General Precautions Removal and Disassembly Confirm the location of the faulty part and find the probable cause of the trouble. Then decide whether removal or disassembly is required. If so, carry out the removal or disassembly according to the steps shown in this service manual.

To prevent erroneous installation and to facilitate installation work, punch or draw alignment marks in places where neither function nor appearance is affected.

Make a distinction between the items removed from one assembly and those removed from another assembly, especially when disassembling a unit having a large number of component parts or when disassembling two or more similar parts. Always do the following: 1. Keep the removed parts in order.

2. Make a distinction between the parts to be replaced and the parts to be reused.

3. When replacing bolts and nuts, use only ones of the specified size.

Special Tools When specified, be sure to use the special tools for the specific service work. Using other tools may cause damage to parts and/or injury to workers.

Non-reusable Parts Whenever any of the following parts are removed, be sure to replace them with new ones.

1. Oil seals 2. Gaskets (except rocker cover gasket) 3. Packings 4. O-rings 5. Lock washers 6. Split pins Recommended Replacement Parts 1. For replacement parts, use only genuine Cat parts.

2. Use of the available sets and kits of service parts is recommended.

3. To unify parts, or for other reasons, service parts are subject to change. When replacing parts in the engine, carefully check for possible modifications by referring to the updated parts catalog for the specific engine.

Genuine Cat Parts

-VIII-

Handling of Electrical System Shocks are harmful to sensors and relays. Never drop or throw them.

When disconnecting a connector, do not pull the harness. Hold the halves of the connector to separate them from each other.

When disconnecting a lock type connector, push the lock lever(s) in the direction(s) shown by the arrow(s).

When connecting a lock type connector, push the plug into the socket until it clicks.

-IX-

Handling of Rubber Hoses and Tubes Take care not to spill gasoline or oil on rubber hoses or tubes, otherwise the rubber is likely to deteriorate.

Greasing During assembly or installation, coat the designated surfaces with the specified grease or oil.

Cooperation When two or more persons work together, each worker should pay attention to the safety of the other(s).

-X-

TABLE OF CONTENTS Forward . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . I How to Read This Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . II Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . VI Precautions for Disassembly and Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . VI General Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . VIII

Determining When to Overhaul the Engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Engine Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Removal Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Installation Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Engine Specifications - Gas and LP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 General Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Major Nuts and Bolts Tightening Torque . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Sealers, Adhesives, and Lubricants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Use of RTV and Anaerobic Sealer (Gasket Eliminator) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Diagnostic Information and Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

11 13 14 16

Base Engine Misfire Diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Engine Compression Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Engine Noise Diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Valve Train Diagnosis (General) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

16 17 18 19

Valve Train Diagnosis (Noise Diagnosis) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Engine Mechanical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Oil Consumption Diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Low or No Oil Pressure Diagnosis and Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Oil Leak Diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Repairing the Leak . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Engine Lubrication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

22 22 22 23 25

Intake Manifold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 Intake Manifold Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 Intake Manifold Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Exhaust Manifold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Oil Level Indicator and Tube Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Exhaust Manifold and Heat Shields Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Exhaust Manifold Clean and Inspect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Exhaust Manifold and Heat Shields Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Oil Level Indicator and Tube Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

34 34 34 35 35

Cylinder Head and Valves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 Valve Rocker Arm Cover Removal (Left) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Valve Rocker Arm Cover Removal (Right) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Valve Rocker Arm and Push Rod Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Valve Lifter Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Valve Stem Oil Seal and Valve Spring Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cylinder Head Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cylinder Head Disassembly and Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cylinder Head Clean and Inspect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Valve Guide Reaming/Valve and Seat Grinding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Valve Stem Oil Seal and Valve Spring Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Valve Lifter Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cylinder Head Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Valve Rocker Arm and Push Rod Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Valve Rocker Arm Cover Left Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Valve Rocker Arm Cover Right Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

-XI-

38 38 39 41 42 43 45 46 48 49 50 51 53 54 55

TABLE OF CONTENTS Oil Pan, Pump and Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 Oil Oil Oil Oil Oil Oil Oil Oil

Pan Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Pump Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Filter Adapter Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Pump Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Pump Assemble . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Filter Adapter Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Pump Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Pan Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

58 59 60 60 62 63 64 65

Front Cover, Timing Chain, and Crankshaft Balancer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67 Engine Front Cover Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Engine Front Cover Oil Seal Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Timing Chain and Sprockets Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Crankshaft Balancer Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Crankshaft Balancer Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Timing Chain and Sprockets Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Engine Front Cover Oil Seal Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Engine Front Cover Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

68 68 68 70 71 72 73 73

Balancer and Camshaft . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77 Balance Shaft Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Camshaft Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Camshaft Bearing Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Camshaft and Bearings Clean and Inspect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Camshaft Bearing Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Camshaft Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Balance Shaft and Bearing Clean and Inspect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Balance Shaft Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

78 80 80 82 83 84 85 86

Crankshaft, Flywheel, Rear Seal, and Bearings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89 Engine Flywheel Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90 Crankshaft Rear Oil Seal and Housing Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90 Crankshaft and Bearings Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91 Crankshaft and Bearings Clean and Inspect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91 Service Prior to Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94 Crankshaft and Bearings Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94 Bearing Clearance Measuring Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95 Micrometer Method for Crankshaft Bearings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95 Crankshaft Rear Oil Seal and Housing Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103 Engine Flywheel Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105

Cylinder Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107 Engine Block Plug Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cylinder Block Clean and Inspect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cylinder Boring and Honing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Reboring the Cylinders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cylinder Block Plug Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

108 110 111 112 113

Piston and Connecting Rod . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117 Piston, Connecting Rod, and Bearing Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Piston and Connecting Rod Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Piston and Connecting Rod and Bearings Clean and Inspect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Piston Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Piston, Connecting Rod and Bearing Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Piston and Connecting Rod Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

118 119 119 122 123 124

Gasoline Carburetor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127 Carburetor Assembly (Upper) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Carburetor Assembly (Lower) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Carburetor Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Air Horn Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

-XII-

129 131 132 132

TABLE OF CONTENTS Carburetor Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Carburetor Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Air Horn Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Carburetor Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Operational Adjustments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Carburetor Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

137 138 140 144 147 148

Electrical Throttle and Governor Control System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149 System Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

ECU Input/Output Interfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

ECU Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Method of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Speed Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

149 150 151 152 152

GM 4.3L, G6 Engine ECU Error Code Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 154 Ignition System and Distributor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157 Ignition System - Distributor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158 Distributor Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159 Distributor Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159 Distributor Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159 Coil Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 160 Coil Installation and Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 160 Ignition Sensing Coil Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 160 Distributor Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161 Ignition Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163 Spark Plug Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163 Alternator and V-Belt (Units built before 01/01/2004) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165

Alternator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167 Accessory Drive Belt Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168

Starter Motor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169 Starter Motor Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170 Fuel System - Gasoline (Units built before 01/01/2004) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173 Fuel Pump and Fuel Hose (Units built before 01/01/2004) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175 Fuel Pump Disassembly and Reassembly (Units built before 01/01/2004) . . . . . . . . . . . . . . . . . . . . 177 Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178 Main Point of Reassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178 Fuel System - LP (Units built before 01/01/2004) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 179 Maintenance Checks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 180 Vacuum Fuel Lockoff Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181 Model J Regulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 182 Pressure Regulator / Converter Service Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 182 On-Truck Pressure Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183 Regulator / Converter Disassembly, Inspection, Cleaning, and Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . 183 Regulator / Converter Bench Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183 Pressure / Converter Regulator Installation Tips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183 Regulator/Lockout - Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183 Impco CA 100 Air Fuel Mixer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 184 LPG Carburetor Adjustment Procedure-co/exhaust Analyzer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 187 Governor Speed Adjustment Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 187 Accelerator Cable Adjustment - LPG . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 188

Special Tools and Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 189

-XIII-

Determining When to Overhaul the Engine

Engine Set-Up and Testing After overhaul, the engine must be tested before it is installed in the truck. If a suitable test stand is not available, the following procedures can be used after the engine is installed in the truck.

Deciding when to overhaul the engine is determined by considering the following factors:

1. Fill the crankcase with the proper quantity and grade of engine oil.

A drop in compression pressure as well as an increase in lube oil consumption and excessive blowby.

Notice: DO NOT use cooling system seal tabs (or similar compounds) unless otherwise instructed.

The use of cooling system seal tabs (or similar compounds) may restrict coolant flow through the passages of the cooling system or the engine components. Restricted coolant flow may cause engine overheating and/or damage to the cooling system or the engine components/assembly.

Lack of power, increase in fuel consumption, drop in lube oil pressure, hard starting and abnormal sound are also engine troubles. These troubles, however, are not always the result of low compression pressure and give no valid reason for overhauling the engine.

2. Fill the cooling system with the proper quantity and grade of coolant.

3. With the ignition OFF or disconnected, crank the engine several times. Listen for any unusual noises or evidence that any of the parts are binding.

4. Start the engine and listen for unusual noises.

5. Check the truck oil pressure gauge or light and confirm that the engine has acceptable oil pressure. If necessary, install an oil pressure gauge and measure the engine oil pressure.

6. Operate the engine at about 1,000 RPM until the engine has reached normal operating temperature.

7. Listen for improperly adjusted or sticking valves, sticking valve lifters or other unusual noises.

8. Inspect for oil and/or coolant leaks while the engine is operating.

9. Verify that the distributor is properly positioned.

10. Perform a final inspection for the proper engine oil and coolant levels.

The engine develops troubles of widely different varieties when its compression pressure drops.

Following are the list of typical troubles caused by this compression pressure fault.

1.

2.

3.

4.

Lack of power Increase in fuel consumption Increase in lube oil consumption Excessive blowby through breather due to worn cylinders, pistons, etc.

5. Excessive blowby due to poor seating of worn inlet and exhaust valves 6. Hard starting 7. Abnormal sound In most cases, these troubles occur concurrently.

Some of them are directly caused by low compression pressure, but others are not. Among the troubles listed above, 1, 2, and 6 could be caused by low compression pressure.

The most valid reason for overhauling the engine is (4). To determine when to overhaul the engine, it is reasonable to take this trouble into consideration in conjunction with the other troubles.

-1-

Engine Replacement

7. Support engine using appropriate sling and hoist. Use existing lifting eyes.

8. Disconnect the fuel line and fuel line clamp.

9. Remove the starter. Refer to Engine Electrical.

10. Disconnect the torque convertor bolts from the flywheel.

11. Support the transmission with a jack.

12. Remove the transmission to engine bolts.

13. Remove the front engine mount bolts.

14. Remove the distributor.

15. Use the engine lifting device to remove the engine from the truck.

Removal Procedure

NOTE If the engine is damaged internally and a new engine assembly is installed in the truck, ensure that all foreign material is flushed out of the cooling system. It is also necessary to flush out the oil cooler system. Failure to rid the oil cooler system of debris can result in engine damage.

1. Disconnect battery.

2. Raise the truck and support with stands.

3. Drain fluids. a. Remove the oil pan drain plug, and allow oil to drain. b. Remove the oil filter. c. Remove both coolant drain plugs and allow coolant to drain.

4. Remove the engine hood and overhead guard.

5. Disconnect the exhaust pipe from the exhaust manifolds.

6. Disconnect the following items: • The wiring harnesses • The throttle cable • The fuel lines

Installation Procedure

NOTE If the engine is damaged internally and a new engine assembly is installed in the truck, ensure that all foreign material is flushed out of the cooling system. It is also necessary to flush out the oil cooler system. Failure to rid the oil cooler system of debris can result in engine damage.

1. Use the engine lifting device to lower the engine into place.

2. Install the engine into the truck.

3. Install the front engine mounts.

4. Install the distributor.

5. Install the following items: • The wiring harnesses • The vacuum lines • The throttle cable • The fuel lines 6. Install torque convertor to flywheel bolts.

7. Install the transmission to engine bolts.

8. Install the oil filter.

9. Install the pump drive shaft.

10. Install the starter. Refer to Engine Electrical.

11. Connect the fuel line and fuel line clamp.

12. Connect the exhaust pipe to the exhaust manifolds.

13. Lower the truck.

14. Fill the crankcase with oil.

15. Fill radiator with coolant.

16. Connect battery.

17. Install engine hood and overhead guard.

-2-

Description and Operation

Piston and Connecting Rod Assemblies The cast aluminum pistons use two compression rings and one oil control assembly. The piston is a low friction, lightweight design with a flat top and barrel shaped skirt. The piston pins are offset 0.9 mm (0.0354 in) toward the major thrust side (right side) to reduce piston slap as the connecting rod travels from one side of the piston to the other side after a stroke. The piston pins have a floating fit in the piston and are retained by a press fit in the connecting rod. The connecting rods are forged steel.

The connecting rods are machined with the rod cap installed for proper clearances and alignments.

Engine Component Description Balance Shaft The cast iron balance shaft is mounted in the crankcase above and in-line with the camshaft. A camshaft gear drives the gear attached to the balance shaft. The front end of the balance shaft is supported by a ball-type bearing. The rear end of the balance shaft uses a sleeve-type bearing.

Camshaft The steel camshaft is supported by four bearings pressed into the engine block. The camshaft timing chain sprocket mounted to the front of the camshaft is driven by the crankshaft sprocket through a camshaft timing chain.

Valve Train Motion is transmitted from the camshaft through the hydraulic roller valve lifters and the tubular valve pushrods to the roller type valve rocker arms. The roller type valve rocker arm pivots on a needle type bearing in order to open the valve. The valve rocker arms for each bank of cylinders are mounted to a one piece valve rocker arm support. Each valve rocker arm is retained on the valve rocker arm support and the cylinder head by a bolt. The hydraulic valve lifters keep all the parts of the valve train in constant contact. Each hydraulic valve lifter acts as an automatic adjuster and maintains zero lash in the valve train. This eliminates the need for periodic valve adjustment.

Crankshaft The cast nodular iron crankshaft is supported by four crankshaft bearings. The number four crankshaft bearing at the rear of the engine is the end thrust bearing. The crankshaft bearings are retained by bearing caps that are machined with the engine block for proper alignment and clearances. The crankshaft position sensor reluctor ring has three lugs used for crankshaft timing and is constructed of powdered metal. The crankshaft position sensor reluctor ring has a slight interference fit onto the crankshaft and an internal keyway for correct positioning.

Drive Belt System Description The drive belt system consists of the following components: • The drive belt • The drive belt tensioner • The drive belt idler pulley • The crankshaft balancer pulley • The accessory drive component mounting brackets • The accessory drive components — The power steering pump, if belt driven — The generator — The engine cooling fan, if belt driven — The water pump, if belt driven — The vacuum pump, if belt driven

Cylinder Heads The cast iron cylinder heads have one intake and one exhaust valve for each cylinder. A spark plug is located between the valves in the side of the cylinder head. The valve guides and seats are integral to the cylinder head. The 4.3L, G6 heavy duty applications have pressed in exhaust valve seats. The valve rocker arms are positioned on the valve rocker arm supports and retained by a bolt.

Engine Block The cast iron engine block has six cylinders arranged in a V shape with three cylinders in each bank. Starting at the front side of the engine block, the cylinders in the left bank are numbered 1-3-5 and cylinders in the right bank are numbered 2-4-6 (when viewed from the rear). The firing order of the cylinders is 1-6-5-4-3-2. The cylinders are encircled by coolant jackets.

Exhaust Manifolds The cast iron exhaust manifolds direct exhaust gases from the combustion chambers to the exhaust system.

Intake Manifold The intake manifold is cast aluminum.

-3-

The drive belt system may use one belt or two belts.

The drive belt is thin so that it can bend backwards and has several ribs to match the grooves in the pulleys. There also may be a V-belt style belt used to drive certain accessory drive components. The drive belts are made of different types of rubbers (chloroprene or EPDM) and have different layers or plys containing either fiber cloth or cords for reinforcement.

Both sides of the drive belt may be used to drive the different accessory drive components. When the back side of the drive belt is used to drive a pulley, the pulley is smooth.

The drive belt is pulled by the crankshaft balancer pulley across the accessory drive component pulleys.

The spring loaded drive belt tensioner keeps constant tension on the drive belt to prevent the drive belt from slipping. The drive belt tensioner arm will move when loads are applied to the drive belt by the accessory drive components and the crankshaft.

The drive belt system may have an idler pulley, which is used to add wrap to the adjacent pulleys.

Some systems use an idler pulley in place of an accessory drive component when the truck is not equipped with the accessory.

Torque Values and / or Fastener Tightening Strategies • Cylinder head bolts, the crankshaft bearing cap bolts, the connecting rod bolts and balance shaft bolt apply a torque angle strategy.

In an on-truck situation where a torque angle meter may not fit into the truck packaging, a three step tightening process may be followed using a torque wrench.

• Certain fasteners should not be reused. Bolts, studs or other fasteners that must be replaced will be called out in the specific service procedures.

Changed Engine Specifications Engine mechanical specifications remain the same as the 1999 products.

New Sealants and / or Adhesives No new sealants or adhesives have been added.

Disassembly and Assembly Procedure Revisions • Valve rocker arm and pushrod • Timing chain and sprockets • Discard all used gaskets, seals or O-ring seals unless otherwise indicated.

Gaskets, seals or O-ring seals that can be reused will be identified in the specific service procedure.

New Product Information The purpose of New Product Information is to highlight or indicate important product changes from the previous model year.

Changes may include one or more of the following items: • A component comparison from the previous year • Fastener changes • Torque values and/or fastener tightening strategies • Changed engine specifications • New sealants and/or adhesives • Disassembly and assembly procedure revisions • Engine mechanical diagnostic procedure revisions • New special tools required Component Comparison • Eliminated the oil filter adapter assembly • Revised the water pump seal • Revised the engine coolant thermostat • New roller type timing chain and sprockets • New roller pivot type valve rocker arm assemblies using a one piece valve rocker arm support to replace the ball pivot type valve rocker arm system • Cylinder heads revised using dry holes for the valve rocker arm bolts

Engine Mechanical Diagnostic Procedure Revisions • Valve Train diagnostic information is now provided in table form.

Potential or probable causes are supplied for each specific concern.

• Engine Noise diagnostic information is now provided in table form.

Potential or probable causes are supplied for each specific concern.

New Special Tools Required No special tools are required.

-4-

Engine Identification • The Truck Identification Number (VIN) Derivative is located on the left side rear of the engine block (1) or on the right side rear (2) and typically is a nine digit number stamped or laser etched onto the engine at the truck assembly plant.

— The first digit identifies the division.

— The second digit identifies the model year.

— The third digit identifies the assembly plant.

— The fourth through ninth digits are the last six digits of the Truck Identification Number (VIN).

569359

• Engines built at the Tonawanda engine plant have the engine identification number located at the right front top of the engine block.

— The first digit (1) is the source code.

— The second and third digits (2) are the month of the build.

— The forth and fifth digits (3) are the date of the build.

— The sixth, seventh and eighth digits (4) are the broadcast code.

195338

• Engines built at the Romulus engine plant have the engine identification number located at the right front top of the engine block.

— The first digit (1) is the source code.

— The second and third digits (2) are the month of the build.

— The forth digit (3) is the hour of the build.

— The fifth and sixth digits (4) are the date of the build.

— The seventh, eighth and ninth digits (5) are the broadcast code.

195339

-5-

Specifications Engine Specifications - Gas and LP-Gas

Application

Specification METRIC

ENGLISH

Engine Engine Model

GM 4.3L, G6

Manufacturer

General Motors

Type

Gasoline / LPG

Cooling System

Water Cooled

No. of Cylinders - Arrangement

6 - 90° V

No. of Stroke

4

Type of Combustion Chamber

Semi - Spherical

Valve Arrangement

Overhead

Type of Cylinder Liner

Integral

Cylinder Bore x Stroke, mm (in) Displacement, cc (cu in)

101.6x88.39

4.00x3.48

4293

262

Compression Ratio

9.2:1

Rated Output, PS/rpm

94 / 2450

Rated Torque, kgf -m/rpm

31.0

1200

Min. rpm

750 ± 50

Max. rpm

2650-2700

Dimensions (LxWxH), mm (in)

710x620x740 (28x24.5x29)

Weight, kg (lbs)

26

572

Installation Position

Rear

Ignition

Spark

Firing Order

1-6-5-4-3-2

Initial Ignition Timing BTDC deg

0° Gasoline, 8° L.P.G.

Rotation (View From Pulley)

CW

Voltage for Electric System

12 V

-6-

Specifications Engine Specifications - Gas and LP-Gas, continued

Application

Specification METRIC

Ignition System Ignition Coil -

Distributor

-

HEI or EST Type

Mold

Manufacturer

AC Delco

Type

Pointless

Manufacturer

AC Delco

Type of Spark Advance Control Spark Plug -

Internal Solid State Circuit

Model

AC R44LTS

Manufacturer

AC Delco

Size, mm (in)

14

0.55

Gap, mm (in)

.889

.035

Fuel System

GAS / LP

Carburetor/ Mixer-Type

IFZ / CA100

Manufacturer Governor -

AISAN Kogyo Co. / IMPCO

Type

Electronic / Pneumatic

Manufacturer Fuel Pump -

ENGLISH

Mitsubishi Heavy Industries / AISAN Kogyo Co.

Type

Electromagnetic

Manufacturer

Jidosha Kiki

Engine Lubrication System Type

Pressure Feed

Oil Pump

Gear Pump

Oil Filter

Paper Element

Oil Cooler

Oil to Water Type

Refill Capacity, Liter (Quart) Oil Pan

4.0 (4.2)

Oil Filter and Cooler

0.7 (0.8)

Total

4.7 (5.0)

-7-

Specifications Engine Specifications - Gas and LP-Gas, continued Application

Specification

Cooling System Type Complete Engine Refill Capacity, Liter (Quarts) Water Pump Thermostat Type/ Opening Temp° F Alternator Type Manufacturer Rated Output, V - A Regulator Starter Type Manufacturer Voltage - Output, V - kW

Forced Circulation 18.2 (4.84) Centrifugal Type, V - Belt Driven Wax Type / 180 3 - Phase AC MANDO 12 - 50 Built in IC Type Electromagnetic Delco Remy 12 V - 0.75

Engine Mechanical Specifications

-8-

Engine Mechanical Specifications,

continued

-9-

Engine Mechanical Specifications,

continued

-10-

Major Nuts and Bolts Tightening Torque

Torque Item

Remarks kgf-m N-m

Balance Shaft Retainer Plate Bolts Balance Shaft Driven Gear Bolt (First Pass) Balance Shaft Driven Gear Bolt (Final Pass) Belt Idler Pulley Bolt Camshaft Retainer Bolt Camshaft Sprocket Bolt Connecting Rod Nut (First Pass) Connecting Rod Nut (Final Pass) Crankshaft Balancer Bolt Crankshaft Bearing Cap (Preferred Method) Crankshaft Pulley Bolt First Pass Final Pass Crankshaft Position Sensor Bolt Crankshaft Rear Oil Seal Housing Nut and Bolt Crankshaft Rear Oil Seal Housing Stud Cylinder Head Bolts (First Pass in Sequence) Cylinder Head Bolts (Long Bolts Final Pass in Sequence) Cylinder Head Bolts (Medium Bolts Final Pass in Sequence) Cylinder Head Bolts (Short Bolts Final Pass in Sequence) Cylinder Head Core Hole Plug Distributor Cap Bolt Distributor Clamp Bolt Drive Belt Tensioner Bolt EGR Valve Bolt (First Pass) EGR Valve Bolt (Final Pass) EGR Valve Inlet Pipe Clamp Bolt EGR Valve Inlet Pipe Nut at Exhaust Manifold EGR Valve Inlet Pipe Nut at Intake Manifold Engine Block Coolant Drain Plug Engine Block Left Rear Oil Gallery Plug Engine Block Oil Gallery Plugs (Left Side, Right Rear) Engine Coolant Heater Bolt/Screw Engine Coolant Temperature (ECT) Sensor Engine Flywheel Bolt Engine Front Cover Bolt Engine Front Lift Bracket Bolt Engine Mount Bracket Bolt to Engine Engine Mount Bracket Nut to Engine Mount Bracket Bolt-Through-bolt Engine Oil Pressure Gauge Sensor Exhaust Manifold Bolts and Stud (First Pass) Exhaust Manifold Bolts and Stud (Final Pass) Front Lift Bracket Stud

NOTE

1.22 2.08 5.09 1.22 2.49 2.77 9.67 5.91 2.08 .81 1.22 .61 3.05

2.08 .24 2.49 5.09 .71 3.05 2.49 3.05 2.49 2.08 3.05 2.08 0.20 2.08 10.25 1.22 1.52 5.11 6.93 3.05 1.52 3.05 3.59

lb•in

12 — 20 15 35 degrees 50 37 12 — 25 18 27 20 70 degrees 95 70

106 —

58 43 20 15 73 degrees 9 — 12 — 6 — 30 22 75 degrees 65 degrees 55 degrees 20 15 2 — 25 18 50 37 7 — 30 22 25 18 30 22 25 18 20 15 30 22 20 15 2 — 20 15 100 74 12 — 15 11 54 40 68 50 30 22 15 11 30 22 35 26

—

Important: Unless otherwise noted all torques are dry.

-11-

lb•ft

— 106 — — —

80 106 53 —

— 21 — — 62 — — — — — — — 18 — — 106 — — — — — — —

Major Nuts and Bolts Tightening Torque,

continued

Torque Item

Remarks kgf-m N-m

Ignition Coil Stud Intake Manifold Bolt (First Pass) Intake Manifold Bolt (Second Pass) Intake Manifold Bolt (Final Pass) Knock Sensor Oil Fill Tube Lower Support Bolt and Stud Oil Fill Tube Nut Oil Fill Tube to Oil Fill Tube Lower Support Bolt Oil Filter Adapter Bolts Oil Filter Fitting Oil Level Indicator Tube Bolt Oil Level Indicator Tube to Oil Fill Tube Lower Support Bolt Oil Pan Baffle Bolt Oil Pan Bolts (Tighten in Sequence) Oil Pan Nuts (Tighten in Sequence) Oil Pan Drain Plug Oil Pan Skid Plate Bolt Oil Pressure Fittings (Plus Necessary Alignment) Oil Pressure Sensor and Switch Oil Pump Bolt-to-Rear Crankshaft Bearing Cap Oil Pump Cover Bolts Spark Plug Wire Support Bolt Spark Plugs (New Cylinder Head) Spark Plugs (All Subsequent Installations) Valve Lifter Guide Retainer Bolt Valve Lifter Push Rod Guide Bolt Valve Rocker Arm Ball Stud Valve Rocker Arm Bolt Valve Rocker Arm Cover Bolts Valve Rocker Arm Nut Water Outlet Stud Water Pump Bolts Water Pump Pulley Bolts

NOTE

1.22 .31 1.22 1.52 2.49 2.49 1.22 0.50 2.08 5.60 1.22 0.50 1.22 2.49 2.49 2.49 2.08 1.52 3.05 9.14 1.22 1.22 3.05 1.52 1.66 1.66 4.85 3.05 1.22 2.49 2.49 4.56 2.49

12 3 12 15 25 25 12 5 20 55 12 5 12 25 25 25 20 15 30 90 12 12 30 15 16 16 47 30 12 25 25 45 25

Important: Unless otherwise noted all torques are dry.

-12-

lb•ft — — — 11 18 18 — — 15 41 — — — 18 18 18 15 11 22 66 — — 22 11 12 12 35 22 — 18 18 33 18

lb•in 106 27 106 — — — 106 44 — — 106 44 106 — — — — — — — 106 106 — — — — — — 106 — — — —

Sealers, Adhesives and Lubricants Application Balancer Shaft Driven Gear Bolt Camshaft Retainer Bolt Crankshaft Balancer Keyway Cylinder Head Bolt Engine Block to Crankshaft Rear Oil Seal Housing Junction at the Oil Pan Sealing Surfaces Engine Block to Engine Front Cover Junction at the Oil Pan Sealing Surfaces Engine Block at the Lower Intake Manifold Sealing Surfaces Engine Block Coolant Drain Hole Plug Engine Block Oil Gallery Plug Engine Coolant Temperature (ECT) Gauge Sensor Engine Oil Engine Oil Pressure Sensor Engine Oil Pressure Sensor Fitting Engine Oil Supplement Exhaust Manifold Bolt/ Stud Expansion Cup Plug (Balance Shaft Rear Bearing Hole) Expansion Cup Plug (Camshaft Rear Bearing Hole) Lower Intake Manifold Bolt Oil Level Indicator Tube Oil Pump Screen Tube Valve Rocker Arm Stud Valve Train Component Prelube Water Pump Bolt

Type of Material Threadlock Threadlock Adhesive Sealant Adhesive

GM Part Number 12345382 12345382 12346141 12346004 12346141

MCFA Part Number A000006061 A000006061 A000000165 2I4256 A000000165

Adhesive

12346141

A000000165

Adhesive

12346141

A000000165

Sealant Sealant Sealant SAE 5W30 Oil Sealant Sealant Lubricant Threadlock Sealant Sealant Threadlock Sealant Sealant Threadlock Lubricant Sealant

12346004 12346004 12346004 12345610 5QT 12346004 12346004 1052367 12345382 12346004 12346004 12345382 12346004 12346004 12345493 12345501 12346004

2I4263 2I4263 2I4263 2I4263 2I4263 A000006061 2I4263 2I4263 A000006061 2I4263 2I4263 2I4256 2I4263

Form-In-Place Gasket (FIPG) The engine has several places where the form-in-place gasket (FIPG) is in use. To ensure the gasket is fully sealed, use the following precautions when applying the FIPG: 1. It is absolutely necessary to apply the sealant in the right amount, evenly and without a break.

2. Bead size, continuity, and location are crucial to a good seal. Too thin a bead causes leakage. Too thick a bead can be squeezed out of location and cause blockage or narrowing in the fluid feed line.

NOTE

Since the FIPG used in the engine hardens as it reacts with moisture in the air, it is normally used in the metallic flange area.

Disassembly The parts assembled with the FIPG can be easily disassembled. Break the seal by striking it with a mallet or by inserting a flat, thin gasket scraper and hammering it through the joint. Use caution to prevent damage to the joined parts.

Surface Preparation Use a gasket scraper or wire brush to thoroughly remove all surface oil and dirt from all gasket application surfaces. Completely remove any old FIPG still remaining in the bolt holes. All application surfaces must be flat.

Form-In-Place Gasket Application Apply the FIPG in a smooth, continuous bead without any breaks. Also cover the bolt hole circumference with an even, continuous bead. Wipe away any excess and mount the parts while the FIPG is still wet (15 minutes or less).

Check the mounted parts and wipe away any excess sealant.

-13-

Use of RTV and Anaerobic Sealer

• Tighten the fasteners in sequence (if specified) and to the proper torque specifications. DO NOT overtighten the fasteners.

Sealant Types Important: The correct sealant and amount of sealant must be used in the proper location to prevent oil leaks, coolant leaks or the loosening of the fasteners. DO NOT interchange the sealants. Use only the sealant (or equivalent) as specified in the service procedure.

The following 2 major types of sealant are commonly used in engines: • Aerobic sealant [Room Temperature Vulcanizing (RTV)] • Anaerobic sealant, which include the following: — Gasket eliminator — Pipe — Threadlock

Anaerobic Type Gasket Eliminator Sealant Anaerobic type gasket eliminator sealant cures in the absence of air. This type of sealant is used where 2 rigid parts (such as castings) are assembled together. When 2 rigid parts are disassembled and no sealant or gasket is readily;y noticeable, then the 2 parts were probably assembled using an anaerobic type gasket eliminator sealant.

Use the following information when using gasket eliminator sealant: • Always follow all the safety recommendations and directions that are on the gasket eliminator sealant container.

• Apply a continuous bead of gasket eliminator sealant to one flange.

The surfaces to be sealed must be clean and dry.

Important: Do not allow the gasket eliminator sealant to enter any blind threaded holes, as the gasket eliminator sealant may prevent the fasteners from clamping properly, seating properly or cause damage when the fastener is tightened.

Apply the gasket eliminator sealant evenly to get a uniform thickness of the gasket eliminator sealant on the sealing surface.

Important: Gasket eliminator sealed joint fasteners that are partially torqued and the gasket eliminator sealant allowed to cure more than 5 minutes, may result in incorrect shimming and sealing of the joint.

• Tighten the fasteners in sequence (if specified) and to the proper torque specifications. DO NOT overtighten the fasteners.

• After properly tightening the fasteners, remove the excess gasket eliminator sealant from the outside of the joint.

Aerobic Type Room Temperature Vulcanizing (RTV) Sealant Aerobic type Room Temperature Vulcanizing (RTV) sealant cures when exposed to air. This type of sealant is used where 2 components (such as the intake manifold and the engine block) are assembled together.

Use the following information when using RTV sealant: • Do not use RTV sealant in areas where extreme temperatures are expected. These areas include: — The exhaust manifold — The head gasket — Any other surface where a different type of sealant is specified in the service procedure • Always follow all the safety recommendations and the directions that are on the RTV sealant container.

• Use a plastic or wood scraper in order to remove all the RTV sealant from the components.

Important: Do not allow the RTV sealant to enter any blind threaded holes, as it may prevent the fasteners from clamping properly or cause damage when the fastener is tightened.

The surfaces to be sealed must be clean and dry.

• Use a RTV sealant bead size as specified in the service procedure.

• Apply the RTV sealant bead to the inside of any bolt hole areas.

• Assemble the components while the RTV sealant is still wet to the touch (within 3 minutes). Do not wait for the RTV sealant to skin over.

Anaerobic Type Threadlock Sealant Anaerobic type threadlock sealant cures in the absence of air. This type of sealant is used for threadlocking and sealing of bolts, fittings, nuts and studs. This type of sealant cures only when confined between 2 close fitting metal surfaces.

Use the following information when using threadlock sealant: • Always follow all safety recommendations and directions that are on the threadlock sealant container.

• The threaded surfaces must be clean and dry.

• Apply the threadlock sealant as specified on the threadlock sealant container.

-14-

Important: Fasteners that are partially torqued and then the threadlock sealant allowed to cure more than five minutes, may result in incorrect clamp load of assembled components.

Tighten the fasteners in sequence (if specified) and to the proper torque specification. DO NOT overtighten the fasteners.

Anaerobic Type Pipe Sealant Anaerobic type pipe sealant cures in the absence of air and remains pliable when cured. This type of sealant is used where 2 parts are assembled together and require a leak proof joint.

Use the following information when using pipe sealant: • Do not use pipe sealant in areas where extreme temperatures are expected. These areas include: — The exhaust manifold — The head gasket — Surfaces where a different sealant is specified • Always follow all the safety recommendations and the directions that are on the pipe sealant container.

• The surfaces to be sealed must be clean and dry.

• Use a pipe sealant bead of the size or quantity as specified in the service procedure.

Important: Do not allow the pipe sealant to enter any blind threaded holes, as the pipe sealant may prevent the fasteners from clamping properly or cause component damage when the fastener is tightened.

• Apply the pipe sealant bead to the inside of any bolt hole areas.

• Apply a continuous bead of pipe sealant to 1 sealing surface.

• Tighten the fasteners in sequence (if specified) and to the proper torque specifications. DO NOT overtighten the fasteners.

-15-

Diagnostic Information and Procedures Base Engine Misfire Diagnosis The following diagnosis information covers common problems and possible causes. When the proper diagnosis is made, the problem should be corrected by adjustment, repair or part replacement, as required. Refer to the appropriate section of the manual for these procedures.

This diagnostic table will assist in engine misfire diagnosis due to a mechanical problem such as a faulty camshaft or leaking headgasket. It is assumed that the base engine timing is correct and the acceptable fuel is being used. The Gasoline engine is equipped with an ECU Diagnostics tester. See Engine Diagnostics Tester section.

-16-

Diagnostic Information and Procedures,

continued

Engine Compression Test

• Piston Rings Leaking- Compression low on first stroke. Tends to build up on the subsequent strokes but does not reach normal. Improves considerably with addition of oil.

• Valves Leaking- Compression low on first stroke. Does not tend to build up on the subsequent strokes. Does not improve much with addition of oil. Use approximately three squirts of oil from a plunger type oiler.

• If two adjacent cylinders have lower than normal compression, and injecting oil into the cylinders does not increase the compression, the cause may be a head gasket leaking between the two cylinders.

5. Install the removed parts.

6. Connect the disconnected components.

1. Engine should be at room temperature. a. Disconnect the Battery terminal and the terminal connector from the distributor. b. Remove the spark plugs. c. Block the throttle body plate wide open. d. Battery should be at or near full charge.

2. For each cylinder, crank engine through four compression strokes (four puffs).

3. The lowest reading cylinder should not be less than 70% of the highest cylinder. No cylinder reading should be less than 689 kPa (100 psi).

For example, if the highest pressure in any one cylinder is 1035 kpa (150 psi), the lowest allowable pressure for any other cylinder would be 725 kpa (105 psi). 1035x70%=725 (150x70%=105).

4. If some cylinders have low compression, inject approximately 15 ml (one tablespoon) of engine oil into the combustion chamber through the spark plug hole.

• Normal - Compression on each cylinder builds up quickly and evenly to specified compression.

-17-

Engine Noise Diagnosis

-18-

Valve Train Diagnosis

Diagnostic Table

-19-

Diagnostic Table, continued

-20-

Valve Train Diagnosis,

continued

-21-

Oil Leak Diagnosis

-22-

Oil Leak Diagnosis, continued

-23-

Drive Belt Tensioner Diagnosis

-24-

Engine Lubrication

44610

Full pressure lubrication, through a full-flow oil filter, is supplied by a gear-type oil pump. Oil is drawn up through the oil pump screen and passes through the pump to the oil filter. The oil filter is a full-flow paper element unit with an anti-drain back valve. An oil filter bypass valve is used to ensure adequate oil supply in the event the filter becomes plugged or develops excessive pressure drop. Filtered oil flows into the main gallery and then to the camshaft,

balance shaft, rear bearing, and crankshaft bearings.

The valve lifter oil gallery supplies oil to the valve lifters. Oil flows from the valve lifters through the hollow valve pushrods to the valve rocker arms. Oil drains back to the crankcase through the oil drain holes in the cylinder head. The camshaft timing chain is drip fed from the front camshaft bearing.

The pistons and piston pins are lubricated by oil splash.

-25-

-26-

Lower Engine View 1

Legend (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) (13) (14) (15) (16) (17) (18) (19) (20) (21) (22) (23) (24)

Oil Level Indicator Tube Bolt Oil Level Indicator Oil Level Indicator Tube Engine Oil Pressure Sensor Fitting Balance Shaft Bearing (Rear) Knock Sensor Expansion Cup (Balance Shaft Rear Bearing Hole) Engine Block Rear Oil Gallery Plug Expansion Cup Plug (Camshaft Rear Bearing Hole) Engine Block Dowel Straight Pin (Transmission Locator) Left Side Oil Gallery Plug Oil Filter Adapter Gasket Oil Filter Adapter Seal (O-ring) Oil Filter Adapter (Typical) Oil Filter Adapter Bolt Oil Filter Oil Filter Fitting Oil Filter Adapter Bolt Oil Filter Bypass Valve Engine Coolant Drain Hole Plug Engine Block Core Hole Plug Dowel Pin (Cylinder Head Locator) Water Pump Gasket

-27-

(25) (26) (27) (28) (29) (30) (31) (32) (33) (34) (35) (36) (37) (38) (39) (40) (41) (42) (43) (44) (45) (46) (47) (48)

Water Pump Water Pump Bolt Front Oil Gallery Plug Camshaft Bearings Engine Camshaft Camshaft Retainer Camshaft Retainer Bolt Balance Shaft Drive Gear Camshaft Sprocket Camshaft Timing Chain Camshaft Sprocket Bolt Balance Shaft Gear Bolt Balance Shaft Driven Gear Balance Shaft Retainer Bolt Balance Shaft Retainer Balance Shaft Piston Ring Set Piston Piston Pin Connecting Rod Bolt Connecting Rod Connecting Rod Bearings Connecting Rod Cap Hex Nut

-28-

Intake Manifold Removal and Installation

Torque Specifications First pass: .31 kgf•m (27 lb•in) [3 N•m] Second pass: 1.22 kgf•m (106 lb•in) [12 N•m] Third pass: 1.52 kgf•m (11 lb•ft) [15 N•m]

N

Removal steps

➧B➧ ➧A ➧

1.

2.

3.

4.

5.

N

Cover - Thermostat Gasket Thermostat Manifold Gasket

-29-

Intake Manifold Removal

9. Remove the intake manifold.

NOTE Important: Make sure the ends of the fuel system lines are properly sealed. Do not allow dirt or debris to enter the fuel system.

1. Drain the engine coolant.

2. Remove the distributor clamp and bolt.

3. Remove the distributor.

31510

10. Remove and discard the intake manifold

Intake Manifold Clean and Inspect 1. Clean the intake manifold in cleaning solvent.

2. Dry the intake manifold with compressed air.

3. Inspect the intake manifold for the following: • Damage to the gasket sealing surfaces (1), (2) • Restricted exhaust gas recirculation system passages • Restricted cooling system passages (3) • Cracks or damage

34403

4.

5.

6.

7.

8.

Remove Remove Remove Remove Remove

the air inlet duct. the throttle linkage. the ignition coil.

PCV valve and vacuum hoses. the intake manifold bolts.

NOTE Important: The intake manifold may be removed as an assembly. Do not remove the intake manifold components unless component service is required.

480570

-30-

➧A

3. Apply a 5 mm (0.197 in.) bead of sealant MCF P/N A000000165 (GM P/N 12346141) or equivalent to the front and rear top of the engine block intake mounting surface. a. Extend the sealant bead 13 mm (0.50 in.) onto the intake manifold gasket. Front and rear of the engine block.

Intake Manifold Installation

NOTE Important: Applying excessive amounts of sealant may prohibit the intake gasket from sealing properly.

1. Apply a 4.0 mm (0.157 in.) patch of adhesive patch of sealant P/N A000000165 (GM 12346141) or equivalent to the cylinder head side of the lower intake manifold gasket at each end front top of the engine block.

NOTE Important: The intake manifold must be installed and the fasteners tightened while the adhesive is still wet to the touch.

2. Install the lower intake manifold gasket onto the cylinder head. Use the gasket locator pins to properly seat the intake manifold gasket on the cylinder head.

b. Install the intake manifold on to engine block. c. Apply threadlock (GM P/N 12345382) or equivalent to the threads of the intake manifold bolts.

4. Install the intake manifold bolts in sequence and torque in the 3 step method.

NOTE Note: Care must be used to apply the correct amount of sealant onto the gaskets. Applying excessive amounts of sealant may prohibit the intake gaskets from sealing properly.

31510

-31-

NOTE Important: Proper manifold fastener tightening sequence and torque are critical. Always follow the tightening sequence and torque the intake manifold bolts using the three (3) step method. Failing to do so may distort the crankshaft bearing bore alignment and cause damage to the crankshaft bearings.

5. Tighten the manifold bolts as shown below.

1st pass .31 Kgf•cm (27 lbf.in) [3 N•m] Tightening torque 2nd pass for intake 1.22 Kgf•cm (106 lbf.in) [12 N•m] manifold Final pass 1.52 Kgf•cm (11 lbf.ft) [15 N•m]

-32-

Exhaust Manifold Removal and Installation

Torque Specifications: First pass: 1.52 kgf•m (11 lb•ft) [15 N•m] Final pass: 3.05 kgf•m (22 lb•ft) [30 N•m]

1

New

2 6 4 5

Removal steps

➧A➧ ➧B ➧

1.

2.

3.

4.

5.

6.

Gauge - Oil Tube - Level Gage Shield - Exhaust Shield - Spark Plug Shield - Spark Plug Manifolds - Exhaust

-33-

3

Oil Level Indicator and Tube Removal

Exhaust Manifold Clean and Inspect

1. Remove oil level indicator from the tube.

2. Remove the oil level indicator tube bolt from the right cylinder head.

3. Remove the oil level indicator tube from the engine block.

! CAUTION Refer to Safety Glasses Caution in Cautions and Notices.

1. Clean the exhaust manifolds in cleaning solvent.

2. Dry the components with compressed air.

3. Inspect the exhaust manifolds for the following: • Damage to the gasket sealing surfaces (1) • Damage to the exhaust gas recirculation (EGR) pipe fitting (2) (left manifold) • Damage to the threaded holes (3) • Restrictions within exhaust passages • Broken or damaged exhaust manifold heat shields (4) (if applicable) • Broken or damaged exhaust manifold

11472

➧ B ➧ Exhaust Manifold and Heat Shields Removal 1. Remove the studs and bolts from the exhaust manifold and heat shields.

2. Remove the exhaust manifold and heat shields.

4. Measure the alignment or surface flatness of the exhaust manifold flanges using a straight edge and a feeler gauge.

Refer to Engine Mechanical Specifications.

If the surface flatness is not within the specifications, the exhaust manifold is warped and must be replaced.

3. Remove and discard the exhaust manifold gaskets.

-34-

Exhaust Manifold and Heat Shields Installation

➧ B ➧ Oil Level Indicator and Tube Installation

1. Install NEW exhaust manifold gaskets.

1. Clean and inspect the tube and indicator for damage or serviceability.

2. Apply a sealer MCF P/N 2I4256 (GM P/N 12346004) or equivalent around the oil level indicator tube 13 mm (0.5 in.) below the bead.

328540

2. Install the exhaust manifold.

3. Install the spark plug heat shields.

4. Use Locktite (G/M P/N 12345382) or equivalent to the threads of the exhaust manifold bolts and stud.

5. Install the exhaust manifold bolts and stud and torque to the specified torque.

Tightening torque 1st pass exhaust manifold bolts

1.52 Kgf•m (11 lb•ft) [15 N•m]

Tightening torque final pass exhaust manifold bolts

3.05Kgf•m (22 lb•ft) [30 N•m]

188009

3. Install the oil level indicator tube into the engine block. Rotate the tube into position.

4. Install the oil level indicator tube bolt to the cylinder head.

Tightening torque oil level indicator 1.22 Kgf•m (106 lb•in) [12 N•m] tube bolt 5. Install the oil level indicator into the tube.

188045

6. Install the spark plug wires to the spark plug wire retainers.

7. Install the spark plug wires onto the spark

-35-

-36-

Cylinder Head and Valves Removal and Installation

Removal steps 1. Rocker Arm Cover 2. Bolts ➧ A ➧ 3. Cylinder Head Assy ➧ B ➧ 4. Gasket 5. Nut 6. Rocker Arm 7. Rocker Arm Support 8. Key 9. Cap 10. Spring 11. Seal 12. Valves

1

Torque Specifications For Cylinder Head Bolts: All bolts first pass in sequence 3.05 kgf•m (22 lb•ft) [30N•m] Long Bolts final pass in sequence 75 degrees Medium Bolts final pass in sequence 65 degrees Short Bolts final pass in sequence 55 degrees

T=2.49 kgf•m (18 lb•ft) [25 N•m]

8 5

3

2

ng

9

Lo

10

Sh

or

t

M

ed

iu

m

6

11

3

12

N

T=4.16 kgf•m (30 lb•ft) [40 N•m]

-37-

Valve Rocker Arm Cover Removal (Left)

7. Remove the valve rocker arm cover gasket.

8. Discard the valve rocker arm cover gasket.

1. Disconnect the negative battery cable.

2. Remove the ignition coil.

3. Disconnect the spark plug wires from the spark plugs.

4. Remove the PCV valve and tube.

5. Remove the rocker arm cover bolts. Discard the grommets from the rocker arm valve cover and replace with new grommets.

328573

Valve Rocker Arm Cover Removal (Right) 1. Disconnect the negative battery cable.

2. Disconnect the spark plug wires from the spark plugs.

3. Remove the crankcase vent tube.

4. Remove the starter relay.

5. Remove the oil level indicator tube.

6. Remove the valve rocker arm cover bolts.

7. Remove the valve rocker arm cover bolt grommets. Discard the valve rocker arm bolt grommets and replace with new grommets.

328566

6. Remove the valve rocker arm cover.

4042

328568

-38-

8. Remove the valve rocker arm cover.

3. Inspect the valve rocker arm cover for the following: • Damage to the PCV valve grommet (1) • Damage to the bolt holes (2) A damaged valve rocker arm cover may interfere with the valve rocker arms.

• Damage to the exterior of the valve rocker arm cover (3) • Gouges or damage to the sealing surface (4) • Damage to the oil fill tube grommet (5) • Restrictions to the ventilation system passages

480524

9. Remove the valve rocker arm cover gasket.

10. Discard the valve rocker arm cover gasket.

334508

Valve Rocker Arm and Push Rod Removal Note: Mark, sort and organize all the components for assembly.

1. Remove the rocker arm cover.

• For the right side of the truck, refer to Valve Rocker Arm Cover Replacement (Left).

• For the left side of the truck, refer to Valve Rocker Arm Cover Replacement (Right).

2. Remove the following components from the cylinder head and place in a part’s rack so they can be reinstalled to their original location.

• The valve rocker arm nuts (former style) • The valve rocker arm balls (former style) • The valve rocker arms

328573

Valve Rocker Arm Cover Clean and Inspect

! CAUTION Safety glasses must be worn or eye injury may occur.

1. Clean the valve rocker arm cover in cleaning solvent.

2. Dry the valve rocker arm cover with compressed air.

-39-

5. Place the following parts in a rack so they can be reinstalled in their original locations: • The valve pushrods • The valve rocker arms

(Former Style)

4045

2a. Remove the valve rocker arms (new style).

(New Style)

4047

Valve Rocker Arm and Push Rods Clean and Inspect Important: Parts that are to be reused must be marked, sorted and organized for assembly.

1. Mark, sort and organize the components for assembly.

480526

3. Remove the valve rocker arm stud (former style).

! CAUTION

(Former Style)

Refer to Safety Glasses Caution in Cautions and Notices.

2. Clean the components with cleaning solvent.

3. Dry the components with compressed air.

4. Inspect the valve rocker arm components for the following: • Valve rocker arm valve push rod socket contact surface (1). The contact surface must be smooth with no scoring or excessive wear.

• Valve rocker arm pivot for binding or damage (2) • Valve rocker arm valve stem contact surface (3) • Valve rocker arm bolt threads for damage (4)

4081

3a. Remove the valve rocker arm supports (new style)

(New Style)

480527

4. Remove the valve pushrods.

-40-

Important: Place the components in a rack so that the components can be reinstalled to their original location.

2. Remove the valve lifters.

4578

NOTE Important: Some valve lifters may be stuck in their bores because of gum or varnish deposits. Use the J 3049 or the J 9290-01 to remove these valve lifters.

3. Use the J 3049 pliers to remove the valve lifters.

Valve Lifter Removal Tools Required • J 3049 Valve Lifter Remover (Plier Type) • J 9290-01 Valve Lifter Remover (Slide Hammer Type) Important: Place the components in a rack so that the components can be reinstalled to their original location.

1. Remove the bolts and the valve lifter push rod guide.

31350

4. If the valve lifters cannot be removed with the J3049, use the J 9290-01 to remove the valve lifters.

4577

-41-

Valve Stem Oil Seal and Valve Spring Removal Tools • • •

Required J 23590 Spark Plug Adapter J 5892-D Valve Spring Compressor J 38606 Valve Spring Compressor

34571

5. Clean the components with cleaning solvent.

6. Dry the components with compressed air.

7. Inspect the valve lifter pushrod guides for excessive wear.

8. Inspect the valve lifter pushrod guides for cracks or damage.

9. Inspect the valve lifter for the following: • Broken or damaged clip (1) • Worn pushrod socket (2) • Scuffed or worn lifter body (3) If the valve lifter shows scuffing or wear, inspect the engine clock valve lifter bores for wear.

• Worn roller (4) • Loose or damaged pin (5) • Plugged oil hole (6)

4041

1.

2.

3.

4.

5.

Remove the valve rocker arm cover.

Remove the valve rocker arms.

Remove the spark plugs.

Install the J 23590.

Apply compressed air to hold the valves in

4048

6. Install the valve rocker arm nut.

7. Use the J 5892-D valve springs compressor.

178485

1964

-42-

3. Remove the following components from the left cylinder head: • The electrical connector at the coolant temperature sensor • Spark plugs

8. Use the J 38606 if clearance does not permit use of J 5892-D.

J 38606

31730

9.

10.

11.

12.

13.

Remove the valve keys.

Carefully release the valve spring tension.

Remove the J 5892-D or J 38606.

Remove the cap, rotator, and spring.

Remove the valve seal.

31868

4. Remove the alternator and bracket from the right cylinder head.

5. Remove valve rocker arm cover.

Cylinder Head Removal 1. Remove the intake manifold.

4041

2. Remove the exhaust manifold.

-43-

8. Remove and discard the cylinder head gasket.

6. Remove the cylinder head bolts.

5131

4047

NOTE

9. Remove the dowel pins (cylinder head locator) (if required).

After removal, place the cylinder head on two wood blocks to prevent damage.

7. Remove cylinder head.

330548

5130

-44-

Cylinder Head Disassembly and Assembly Disassembly Tools Required • J 8062 Valve Spring Compressor

! CAUTION Compressed valve springs have high tension against the valve spring compressor.

Valve springs that are not properly compressed by or released from the valve spring compressor can be ejected from the valve spring compressor with intense force. Use care when compressing or releasing the valve spring with the valve spring compressor and when removing or installing the valve stem keys. Failing to use care may cause personal injury.

31715

(1) Key (2) Cap

(3) Seal (4) Spring

(5) Valve (6) Valve

Assembly Tools Required • J 8062 Valve Spring Compressor • J 42073 Valve Stem Oil Seal Installer 1. Clean the valve spring seat area.

2. Install the valve into the proper port.

! CAUTION Refer to Safety Glasses Caution in Cautions and Notices.

1. Use J 8062 to compress the valve springs.

NOTE J 8062

Important: In order for tool J 42073 to work properly, the valve is installed into the cylinder head.

3. Lubricate guide and valve stem oil seals (3) with clean engine oil.

NOTE Important: Install the valve stem oil seal (3) onto the valve stem (5 or 6). Push the seal down until the seal contacts the valve guide (2).

4. Valve stem oil seal alignment onto the valve guide is critical.

34468

2.

3.

4.

5.

6.

Remove the valve stem keys (1).

Remove the cap (2) from the valve (5 or 6).

Remove the valve spring (4).

Remove the valve stem oil seal (3).

Remove the valve (5 or 6). Place the valves in a rack in the proper sequence so you can install them in the same order.

36371

-45-

5. Place the J 42073 over the valve stem and oil seal. Lightly tap on the J 42073 until the tool bottoms out against the valve spring seat.

6. Install the valve spring (4).

J 8062

NOTE Important: A correctly installed seal should not bottom against the valve guide. There should be a 1-2 mm (0.03937-0.07874 in.) gap (2) between the bottom edge of the seal (5) and the valve guide (4).

34468

Cylinder Head Clean and Inspect Tools Required • J8089 Carbon Removing Brush • J 9666 Valve Spring Tester • J 8001 Dial Indicator Set 1. Clean the valve stems and cylinder heads on a buffing wheel.

2. Clean the following components in cleaning solvent: • Valve stem keys • Valve spring cap • Valve spring • Cylinder head 3. Dry the components with compressed air.

4. Use the J 8089 to clean the carbon from the combustion chambers and the valve area. Be careful not to scuff the chamber.

36373

7. Install the cap (2) on the valve stem.

8. Use the valve spring compressor J 8062 to compress the valve spring.

9. Install the valve stem keys (1).

• Use grease to hold the keys in place while disconnecting the valve spring compressor J 8062.

• Make sure the keys seat properly in the upper groove of the valve stem.

• Tap the end of the stem with a plastic-faced hammer to seat the keys if necessary.

10. Measure the valve spring installed height from the valve spring seat to the locating surface on the cap.

! CAUTION Safety glasses must be worn or eye injury may occur.

J 8089

-46-

9. Valve stems (1) with excessive valve guide (2) clearance must be repaired or the cylinder head replaced.

5. Inspect the cylinder head for the following: • Damage to the gasket surfaces • Damage to the threaded bolt holes • Burnt or eroded areas in the combustion chambers • Cracks in the exhaust ports and combustion chambers • External cracks in the water chambers • Restrictions in the intake or exhaust passages • Restrictions in the cooling system passages • Rusted, damaged or leaking core plugs 6. Measure the cylinder head for warpage with a straight edge and feeler gauge.

• A cylinder head block deck with warpage in excess of 0.10 mm (0.004 in) withing a 152.4 mm (6.0 in) area must be repaired or replaced.

• A cylinder head exhaust manifold deck with warpage in excess of 0.05 mm (0.002 in) withing a 152.4 mm (6.0 in) area must be repaired or replaced.

• A cylinder head intake manifold deck with warpage in excess of 0.10 mm (0.004 in) withing a 152.4 mm (6.0 in) area must be repaired or replaced.

7. Use the valve spring tester J 9666 to measure the valve spring.

• Replace the intake valve spring if the spring tension is less than 360 N (81 lb) at 45.2 mm (1.78 in.).

• Replace the exhaust valve spring if the spring tension is less than 425 N (96 lb) at 45.2 mm (1.78 in.).

156172

10. Measure the valve stem-to-bore clearance.

Excessive valve stem-to-bore clearance may cause excessive oil consumption and may cause a valve to break. Insufficient clearance will result in noisy and sticky functioning of the valve and will disturb the engine assembly smoothness. a. Clamp the dial indicator J 8001 on the exhaust port side of the cylinder head. b. Locate the indicator so the movement of the valve stem from side to side (crosswise to the cylinder head) will cause a direct movement of the indicator stem. The indicator stem must contact the side of the valve stem just above the valve guide. c. Drop the valve head about 1.6 mm (0.064 in.) off the valve seat. d. Use light pressure when moving the valve stem from side to side to obtain clearance reading.

J 9666

4960

8. Inspect the valve spring for squareness.

J 8001 40075

35214

-47-

Valve Guide Reaming / Valve and Seat Grinding

! CAUTION Safety glasses must be worn or eye injury may occur.

Tools Required • J 8001 Dial Indicator Set • J 5830-02 Valve Guide Reamer Set 1. Measure the valve stem-to-guide clearance.

Refer to Cylinder Head Clean and Inspect.

NOTE Important: Exhaust valves with excessive valve stem-to-guide clearance must be replaced with the available service valve that has an 0.0774 mm (0.0305 in) oversize valve stem. The intake valves are NOT available with oversize valve stems.

Replace the cylinder head if after using a NEW intake valve and in order to measure the valve stem-to-guide clearance, the valve stem-to-guide clearance is not within specifications.

3. Use the J 5830-3 in order to ream the exhaust valve guide in order to achieve the correct valve stem-to-guide clearance.

4. Always recondition the exhaust valve seat after reaming the exhaust valve guide bores and installing new exhaust valves.

J 8001

35214

2. Improper valve stem (1) to valve guide (2) clearance may cause excessive oil consumption.

480556

5. Inspect the valves for the following: • Burnt or damaged areas (1) • Undersize margain (2) • Bent stem (3) • Scoring or other damage to the stem (4) • Worn key groove (5) • Worn stem tip (6) 156172

-48-

• Reface pitted valves on a valve refacing machine in order to ensure the correct relationship between the valve head and the valve stem.

Replace the valve if the valve stem is excessively worn or wrapped.

Replace the valve if the edge margain (4) of the valve head is less than 0.79 mm (0.031 in) thick after grinding.

• Several different types of equipment are available for reconditioning valves and valve seats. Follow the equipment manufacturer’s recommendations for equipment use to attain the proper results.

156174

6. Inspect the valve contact for the following: • Undersize margain (1) • Pitted surfaces (2) • Burnt or eroded areas (3) • Acceptable edge (margain) (4) Valves with excessive damage must be replaced. Minor imperfections of the valve or valve seat may be repaired.

Cylinder Head Assemble Tools Required • J 8062 Valve Spring Compressor • J 42073 Valve Stem Seal Installer Important: The exhaust valve oil stem seal has the letters EX (1) molded into the top of the seal. The exhaust valve oil stem seal material is brown in color (2) with a white stripe (3) painted onto the outside diameter of the seal, or the material may be red in color (2) with no paint stripe. The intake valve oil seal is black in color.

1. Assemble the valve into the proper valve guide.

2. Select the proper valve stem oil seal for the specific valve guide.

3. Lubricate the valve stem oil seal and the outside diameter of the valve guide with clean engine oil.

156173

7. Reconditioning of the valves and valve seats: • The valves must seat perfectly for the engine to deliver optimum power and performance.

• Cooling the valve heads is another important factor. Good contact between each valve and valve seat in the cylinder head is necessary to insure that the heat in the valve head is properly carried away.

• Regardless of what type of equipment is used, it is essential that the valve guide bores are free from carbon or dirt in order to ensure the proper centering of the pilot in the valve guide.

The valve seats should be concentric to within 0.05 mm (0.002 in) total indicator reading.

4. Assemble the valve stem oil seal onto the valve stem.

-49-

9. Use the valve spring compressor J 8062 in order to compress the valve springs.

10. Install the valve stem keys.

10.1 Use grease in order to hold the valve stem keys in place while disconnecting the valve spring compressor J 8062.

10.2 Look to ensure that the valve stem keys seat properly in the upper groove of the valve stem.

10.3 Tap the end of the valve stem with a plastic-faced hammer in order to seat the valve stem keys, if necessary.

! CAUTION Safety glasses must be worn or eye injury may occur.

5. Install the valve stem oil seal onto the valve guide using the valve stem seal installer J 42073.

Tap the valve stem oil seal onto the valve guide until the valve stem seal installer J 42073 bottoms against the valve spring seat.

6. Inspect the valve stem oil seal. The valve stem oil seal should not be bottomed against the valve guide.

J 8062

36373

Valve Lifter Installation

7. Install the valve spring (3).

8. Install the valve spring cap (2) onto the valve spring (3) and over the valve stem.

NOTE Parts that are to be reused must be marked, sorted and organized for assembly. If reusing the valve lifters, install the valve lifters in the original positions.

1. Apply engine oil to the valve lifter rollers.

2. Install the valve lifters.

3. Install the valve lifter pushrod guides.

480555

! CAUTION Compressed valve springs have high tensions against the valve spring compressor. Valve springs that are not properly compressed by or released from the valve spring compressor can be ejected from the valve spring compressor with intense force. Use care when compressing or releasing the valve spring with the valve spring compressor and when removing or installing the valve stem keys. Failing to use care may cause personal injury.

Tightening torque for valve lifter pushrod guide bolts

-50-

1.66 Kgf•m (12 lb ft) [16 N•m]

5. Install the cylinder head onto the engine block.

Guide the cylinder head carefully into place over the dowell pins and the cylinder head gasket.

Cylinder Head Installation Tools Required • J 36660 Electronic Torque Meter 1. Clean the cylinder head gasket surfaces on the engine block.

2. Inspect the dowel pins (cylinder head locators) for proper installation.

3. Clean the cylinder head gasket surfaces on the cylinder head.

480536

6. Apply sealant P/N 2I4256, GM P/N 12346004 or equivalent to the threads of the cylinder head bolts.

7. Install the cylinder head bolts finger tight.

334303

NOTE Do not use any type of sealer on the cylinder head gasket (unless specified).

480533

4. Install the NEW cylinder head gasket in position over the dowel pins (cylinder head locators).

8. Tighten the cylinder head bolts in sequence and use the two step method.

Tightening torque for cylinder head bolts

First Pass 3.05 Kgf•m (22 lb ft) [30 N•m] Final Pass Long bolts 75 degrees Medium bolts 65 degrees Short bolts 55 degrees

9. Use the electronic torque meter J 36660 to tighten the cylinder head bolts in sequence on the final pass.

• Tighten the long bolts (1,4,5,8 and 9) on the final pass in sequence to 75 degrees.

• Tighten the medium bolts (12 and 13) on the final pass in sequence to 65 degrees.

• Tighten the short bolts (2,3,6,7,10 and 11) on the final pass in sequence to 55 degrees.

334299

-51-

13. If reusing the engine coolant temperature gauge sensor (if applicable), apply sealant GM P/N 12346004 or equivalent to the threads of the engine coolant temperature gauge sensor.

14. Install the engine coolant temperature gauge sensor (if applicable).

Tightening torque for coolant temperature gauge

2.07 Kgf•m (15 lb ft) [20 N•m]

5132

10. Install the spark plug wire support and bolts.

Tightening torque for wire support and bolts

1.22 Kgf•m (106 lbf.in) [12 N•m]

15. If reusing the engine coolant temperature sensor (if applicable), apply sealant GM P/N 12346004 or equivalent to the threads of the engine coolant temperature sensor.

16. Install the engine coolant temperature sensor (if applicable).

328588

11. Measure the NEW spark plugs for the proper gap. Adjust the spark plug gap if necessary.

Specification Spark plug gap to .889 mm (0.035 in).

12. Install the spark plugs.

Tightening torque for spark plugs NEW

3.05 Kgf•m (22 lb ft) [30 N•m]

USED PLUGS

1.52 Kgf•m (11 lb ft) [15 N•m]

Tightening torque for coolant temperature sensor

328582

-52-

2.07 Kgf•m (15 lb ft) [20 N•m]

Valve Rocker Arm and Push Rod Installation

4. Install the valve rocker arm assemblies as follows: 4.1 Finger start the bolt at location (1) 4.2 Finger start the bolt at location (2) 4.3 Finger start the bolt at location (3) 4.4 Finger start the remaining valve rocker arm bolts.

Important: Be sure to keep parts in order. Parts must be reinstalled into the original location and position.

1. Install the valve pushrods.

480529

NOTE 480580

Be sure that the arrow on the valve rocker arm support is in the up position.

5. Rotate the crankshaft balancer to position the crankshaft balancer alignment mark (1) 57-63 degrees clockwise or counterclockwise from the engine front cover alignment tab (2).

2. Install the valve rocker arm supports.

3. Apply prelube GM P/N 12345501 or equivalent to the following valve rocker arm contact surfaces: • Valve pushrod socket (1) • Roller pivot (2) • Valve stem tip (3)

334551

NOTE Once the valve rocker arm assemblies are installed and properly torqued, no additional valve lash adjustment is required.

6. Tighten the valve rocker arm bolts.

Tightening torque for valve rocker arm bolts

-53-

3.05 Kgf•m (22 lb ft) [30 N•m]

Valve Rocker Arm Cover Installation (Left)

4. Install the valve rocker arm cover bolts and torque to the specified torque.

Important: Do not reuse the valve rocker arm cover gasket or the valve rocker arm cover grommets.

1. Install the NEW valve rocker arm cover gasket into the groove of the valve rocker arm cover.

2. Install the NEW valve rocker arm cover bolt grommets into the valve rocker arm cover.

Tightening torque for valve rocker arm bolts

3.05 Kgf•m (22 lbf.ft) [ 30 N•m]

4041

328573

5. Install PCV valve and tube.

6. Connect the spark plug wires to the spark plugs and route the wires so that they do not touch the engine or exhaust system.

7. Install the ignition coil.

8. Connect the negative battery cable.

3. Install the valve rocker arm cover onto the cylinder head.

480519

31868

-54-

Valve Rocker Arm Cover Installation (Right)

4. Install the valve rocker arm cover bolts and torque to the specified torque.

Important: Do not reuse the valve rocker arm cover gasket or the valve rocker arm cover bolt grommets.

1. Install the NEW valve rocker arm cover gasket into the groove of the valve rocker arm cover.

2. Install the NEW valve rocker arm cover bolt grommets into the valve rocker arm cover.

Tightening torque for valve rocker arm bolts

3.05 Kgf•m (22 lbf.ft) [ 30 N•m]

328573 328568

3. Install the valve rocker arm cover onto the cylinder head.

480524

-55-

-56-

Oil Pan, Pump and Filter Removal and Installation

N

N

Removal steps 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

16.

17.

18.

19.

20.

21.

Plug Pan Gasket Bolt Pump Retainer Shaft Pin Pin Cover Screen Plug Valve Spring Filter Fitting Valve Adapter, Oil Filter Gasket Connector, Cooler Gasket

N

-57-

Oil Pan Removal

5. Remove oil filter adapter bolts.

6. Remove oil filter adapter gasket.

7. Remove oil filter adapter O-ring seal, if equipped.

1. Remove the water pump.

2. Remove crankshaft balancer.

4555

8. Remove the oil pan.

42882

3. Drain the engine oil.

4. Remove the following fasteners from the oil pan: • The bolts • The nuts

330568

9. Remove the oil pan gasket.

10. Discard the oil pan gasket and replace with NEW at reassembly.

NOTE Important: Discard old oil pan gasket.

330559

387757

-58-

Oil Pump Removal

Oil Pan Clean and Inspect

1. Remove the bolt that attaches the oil pump to the rear crankshaft bearing cap.

1. Remove the oil pan baffle bolts and the oil pan baffle.

4548

2. Remove the oil pump driveshaft and the 387763

! CAUTION Safety glasses must be worn or eye injury may occur.

2. Clean the oil pan and the oil pan baffle in cleaning solvent.

3. Dry the oil pan and the oil pan baffle with compressed air.

4. Inspect the oil pan for the following: • Gouges or damage to the oil pan sealing surfaces (1) • Damage to the threaded holes (2) • Damaged oil pan drain hole threads (3) • Damage to the oil pan baffle • Damage to the exterior of the oil pan A damaged oil pan may interfere with the proper position of the oil pump screen, or may not distribute oil properly in the oil pan sump area.

4549

3. Inspect the pins (oil pump locator) for damage, and replace the pins if required.

330578

4554

-59-

2. Remove the oil filter adapter and gasket.

5. Install the oil pan baffle and the bolts.

Tightening torque for oil pan baffle bolts

1.22 Kgf•m (106 lb in) [12 N•m]

4555

3. Remove the seal.

387763

Oil Filter Adapter Removal 1. Remove the oil filter adapter bolts.

4556

Oil Pump Disassemble 1. Remove the oil pump drive shaft and oil pump driveshaft retainer.

4554

5274

-60-

2. If necessary, remove the oil pump screen.

• The oil pump screen has a press fit into the pump cover.

• Do not remove the screen from the pipe.

The pipe and screen are serviced as a complete assembly

5. Remove the drive gear and the driven gear.

6. Matchmark the gear teeth for assembly.

5278

7. Remove the following items: a. The oil pump pressure relief valve spring straight pin. b. The oil pump pressure relief spring c. The oil pump pressure relief valve

5275

3. Remove the oil pump cover bolts.

30401

Oil Pump Clean and Inspect 1. Clean the oil pump components in cleaning solvent.

2. Dry the components with compressed air.

3. Inspect the oil pump for the following conditions: • Scoring gears (2) for the following: • Damaged gears (2) for the following: ❍ Chipping ❍ Gailing ❍ Wear • Scoring, damage or casting imperfections to the body (3) • Damaged or scored gear shaft (4) • Damaged or scored gear shaft (5) • Damaged bolt hole threads • Worn oil pump driveshaft bore • Damaged or sticking oil pump pressure relief valve (minor imperfections may be removed with a fine oil stone) • Collapsed or broken oil pump relief valve spring

5276

4. Remove the pump cover.

5277

-61-

3. Coat the drive gear, the driven gear and the housing gear surfaces with clean engine oil.

4. Install the drive gear and the driven gear into the pump body. a. Align the matchmarks on the gears. b. Install the smooth side of the gear toward the pump cover.

186750

4. If the oil pump is to be reused, install a NEW oil pump pressure relief valve spring.

5. During oil pump installation, install a NEW oil pump driveshaft retainer.

5278

Oil Pump Assemble

5. Install the pump cover.

Tools Required • J 21882 Oil Pump Screen Installer.

NOTE Important: Replace the pressure relief valve spring when you reuse the oil pump.

1. Apply clean engine oil to the oil pump pressure relief valve, oil pump pressure relief valve spring and oil pump body.

2. Install the following items: a. The oil pump pressure relief valve b. The oil pump pressure relief valve spring c. The oil pump pressure relief valve spring straight pin

5277

6. Install the cover bolts.

Tightening torque for cover bolts

1.22 Kgf•m (106 lb•in) [12N•m]

7. Inspect the pump for smoothness of operation by turning the oil pump driveshaft by hand.

30401

-62-

9. Install the oil pump drive shaft and the NEW oil pump drive shaft retainer.

5276 5274

8. Install the oil pump screen. a. If removed, replace the oil pump screen. The oil pump screen must have a good press fit into the oil pump body. b. Mount the oil pump in a soft jawed vise. c. Apply sealant MCF P/N 2I4256 GM P/N 12346004 or equivalent to the end of the oil pump screen pipe. d. Use the oil pump screen installer J 21882 and a soft-faced hammer to tap the oil pump screen into the pump body. The screen must align parallel with the bottom of the oil pan when it is installed.

Oil Filter Adapter Installation 1. Install the seal.

4556

2. Install the oil filter adapter and gasket.

J 21882

5280

NOTE Install a NEW oil pump driveshaft retainer during assembly.

4555

-63-

3. Install the oil filter adapter bolts.

4554

330576

4. Install the oil pump bolt attaching the oil pump to the rear crankshaft bearing cap. Tighten to the specified torque.

Oil Pump Installation 1. Inspect for properly installed pins (oil pump locator).

Tightening torque for 9.14 Kgf•m (66 lb ft) [90 N•m] Oil pump bolts

330572

330578

Important: DO NOT reuse the oil pump driveshaft retainer. During assembly, install a NEW oil pump driveshaft retainer.

2. Install the oil pump.

3. Position the oil pump onto the pins.

-64-

Oil Pan Installation

Important: Always install a NEW oil pan gasket.

The oil pan gasket and oil pan must be installed and the fasteners tightened while the adhesive is still wet to the touch.

3. Install the NEW oil pan gasket into the groove in the oil pan.

1. Apply a 5 mm (0.197 in) wide and 25 mm (1.0 in) long bead of PERMATEX® Gasket Maker P/N A000000165 GM P/N 12346141 or equivalent to both the right and left sides of the engine front cover to engine block junction at the oil pan sealing surfaces.

317310 387757

2. Apply a 5 mm (0.197 in) wide and 25 mm (1.0 in) long bead of PERMATEX® Gasket Maker P/N A000000165, GM P/N 12346141 or equivalent to both the right and left sides of the crankshaft rear oil seal housing to engine block junction at the oil pan sealing surfaces.

Important: The oil pan alignment must always be flush or forward no more than 0.3 mm (0.011 in) from the rear face of the engine block.

4. Install the oil pan onto the engine block.

Press the oil pan gasket into the grooves of the engine front cover and crankshaft rear oil seal housing.

5. Slide the oil pan back against a suitable straight edge.

317313

330568

-65-

6. Install the oil pan bolts and nuts, but do not tighten.

7. Measure the pan-to-transmission housing clearance using a feeler gauge and a straight edge.

Use a feeler gauge to check the clearance between the oil pan-to-transmission housing measurement points. If the clearance exceeds 0.3 mm (0.011 in) at any of the 3 oil pan-totransmission housing measurement points (1), then repeat the step until the oil pan-totransmission housing clearance is within the specification. The oil pan must always be forward of the rear face of the engine block.

10. Install a NEW oil pan drain plug seal (O-ring) onto the oil pan drain plug.

11. Install the oil pan drain plug into the oil pan.

Tightening torque for oil pan drain plug

2.49 Kgf•m (18 lb•ft) [25N•m]

188048

12. Install the NEW engine oil level sensor (if applicable).

38496

Tightening torque for oil level sensor

Notice: If the clearance is more than 0.3 mm (0.011 in), powertrain durability may be reduced.

8. Tighten the oil pan bolts and nuts in sequence (1-12).

9. Measure the clearance between the 3 oil panto-transmission housing measurement points in order to ensure proper alignment.

Tightening torque for oil pan nuts and bolts

2.49 Kgf•m (18 lb•ft) [25N•m]

38481

-66-

13.2 kgf•m (115 lb in) [13N•m]

Front Cover, Timing Chain, and Crankshaft Balancer Removal and Installation

8 7 3 4

6

9 5 2

Removal steps 1.

2.

3.

4.

5.

6.

7.

8.

9.

1

-67-

Cover Seal Bolt Sprocket Chain Drive Gear Bolt Gear Sprocket

Engine Front Cover Removal

Engine Front Cover Oil Seal Removal

1.

2.

3.

4.

1. Disconnect the negative battery cable.

2. Remove the crankshaft balancer.

3. Remove the crankshaft front seal.

Remove Remove Remove Remove

the the the the

crankshaft balancer. water pump. crankshaft position sensor bolt. crankshaft position sensor.

Timing Chain and Sprockets Removal Tools Required • J 23523-F Crankshaft Balancer Remover and Installer • J 5825-A Crankshaft Sprocket Puller

NOTE Check the camshaft timing chain free play. Replace the camshaft timing chain if it can be moved back and forth in excess of 16 mm (0.625 in.).

1. Remove the engine front cover.

2. Check the camshaft timing chain free play.

2.1. Rotate the camshaft sprocket (1) counterclockwise until all slack is removed from the camshaft timing chain (2).

2.2. Measure the free play on the slack side (3) of the camshaft timing chain.

If the camshaft timing chain can be moved side to side in excess of 11 mm (0.43 in), replacement of the camshaft timing chain and the sprockets is recommended during assembly.

5. Remove the crankshaft position sensor seal (O-ring).

6. Discard the crankshaft position sensor seal (O-ring).

7. Remove the engine front cover bolts.

8. Remove the engine front cover.

9. Discard the engine front cover.

NOTE Do not reuse the engine front cover. Always install a new engine front cover.

480542

-68-

3. Remove the crankshaft position sensor reluctor ring.

6. Remove the crankshaft sprocket using the crankshaft sprocket puller J 5825-A. J 5825 - A

480541

7. Remove the camshaft balancer key.

4. Remove the camshaft sprocket bolts.

387761

Timing Chain and Sprockets Clean and Inspect

480544

5. Remove the camshaft sprocket and the camshaft timing chain.

! CAUTION Refer to Safety Glasses Caution in Cautions and Notices.

1. Clean the components with cleaning solvent.

2. Dry the components with compressed air.

3. Inspect the camshaft timing chain for binding or wear.

480546

! CAUTION Safety Glasses must be worn or eye injury may occur.

-69-

4. Inspect the camshaft sprocket and the crankshaft sprocket for the following: • Broken teeth (1) • Damaged teeth (2) • Chipped teeth (3) • Worn teeth • Uneven wear on the edge of the teeth • Worn valleys between the sprocket teeth • Crankshaft sprocket keyway for wear

3. Use the balancer remover and installer J23523-F in order to remove the crankshaft balancer. a. Install the balancer remover and installer J23523-F plate and bolts onto the crankshaft balancer and tighten.

Tightening torque for Balancer bolts

2.49 Kgf•m (18 lb ft) [25 N•m]

b. Install the balancer remover and installer J23523-F forcing screw into the plate. c. Rotate the balancer remover and installer J23523-F forcing screw clockwise in order to remove the crankshaft balancer.

4. Remove the balancer remover and installer J23523-F from the crankshaft balancer.

J 23523-F

Crankshaft Balancer Removal Tools Required • J 23523-F Balancer Remover and Installer 1. Remove the crankshaft balancer bolt and washer.

4059

Important: If replacing the crankshaft balancer, NEW weights must be installed into the NEW crankshaft balancer, in the same location as the old weights in the old balancer.

5. Note the position and length of any crankshaft balancer front groove pins, if applicable.

173172

2. Remove the bolts and the crankshaft pulley.

334258 188055

-70-

b. Install the J 23523-F screw into the end for the crankshaft. c. Install the J 23523-F bearing, the washer and the nut onto the J 23523-F screw. d. Rotate the J 23523-F nut clockwise until the crankshaft balancer hub is completely seated against the crankshaft position sensor reluctor ring.

6. Remove the J 23523-F.

Crankshaft Balancer Installation Tools Required • J 23523-F Crankshaft Balancer Remover and Installer 1. Look to ensure that the front groove pin (crankshaft balancer) is installed in the proper location (if applicable).

J 23523–F

334258 4065

Important: The inertial weight section of the crankshaft balancer is assembled to the hub with a rubber type material. The correct installation procedures (with the proper tool) must be followed or movement of the inertial weight section of the hub will destroy the tuning of the crankshaft balancer.

2. Apply a small amount of adhesive A000000165, GM P/N 12346141 or equivalent onto the crankshaft balancer keyway in order to seal the crankshaft balancer keyway and crankshaft joint.

3. Align the keyway of the crankshaft balancer with the crankshaft balancer key.

4. Install the crankshaft balancer onto the end of the crankshaft.

7. Install the crankshaft pulley and bolts.

Tightening torque for Crankshaft pulley bolts 5.94 Kgf•m (43 lb ft) [58 N•m]

8. Ensure that the crown of the crankshaft balancer washer (2) is faced away from the engine.

1

2 342203

9. Install the crankshaft balancer washer and the bolt, tighten to the specified torque.

Tightening torque for Crankshaft Balancer bolt 188059

5. Use the J 23523-F in order to press the crankshaft balancer onto the crankshaft. a. Install the J 23523-F plate and bolts onto the front of the crankshaft balancer and tighten to the specified torque.

Tightening torque for 2.49 Kgf•m (18 lb ft) [25 N•m] Balancer bolts

-71-

9.67 Kgf•m (70 lb•ft) [95N•m]

Timing Chain and Sprockets Installation

4. Rotate the crankshaft until the crankshaft sprocket is at the 12 o’clock position.

Important: Install the crankshaft sprocket with the alignment mark at the 6 o’clock position.

5. Install the crankshaft sprocket and the camshaft timing chain.

Tools Required • J 5590 Crankshaft Sprocket Installer 1. Install the key into the crankshaft keyway.

The crankshaft balancer key should be parallel to the crankshaft or with a slight incline.

387766

2. Align the keyway of the crankshaft sprocket with the crankshaft balancer key.

3. Use the crankshaft sprocket installer J 5590 to install the crankshaft sprocket.

480546

6. Look to ensure that the crankshaft sprocket is aligned at the 12 o’clock position and the camshaft sprocket is aligned at the 6 o’clock position.

J 5590 480574

480575

-72-

Engine Front Cover Oil Seal Installation

Important: Do not use a hammer to install the camshaft sprocket onto the camshaft. To do so may dislodge the expansion cup plug (camshaft rear bearing hole).

Tools Required • J 35468 Crankshaft Seal Installer and Centering Tool 1. Install the crankshaft front seal.

2. Install the crankshaft balancer.

7. Install the camshaft sprocket bolts.

Tightening torque for camshaft sprocket bolts

Engine Front Cover Installation

2.49 Kgf•m (18 lb•ft) [25N•m]

NOTE Once the composite engine front cover is removed DO NOT reinstall the engine front cover. Always install a new engine front cover.

Tightening torque for front cover bolts

1.22 Kgf•m (106 lb•in) [12 N•m]

1. Install the NEW engine front cover.

2. Install the front cover bolts.

480544

8. Install the crankshaft position sensor reluctor ring. a. Align the keyway on the crankshaft position sensor reluctor ring with the crankshaft balancer key in the crankshaft. b. Use the crankshaft sprocket installer J 5590 to push the crankshaft position sensor reluctor ring onto the crankshaft until completely seated against the crankshaft sprocket.

4068

J 5590

480574

-73-

Water Pump Removal

Important: Do not reuse the original crankshaft position sensor seal (o-ring). When installing the crankshaft position sensor, be sure the crankshaft position sensor is fully seated and held stationary in the engine front cover crankshaft position sensor bore. A crankshaft position sensor that is not completely seated will cock in the engine front cover and may result in erratic engine operation.

Tools Required • J 41240 Fan Clutch Remover and Installer 1. Remove the bolts and the fan and water pump pulley using the J 41240.

3. Lubricate the NEW crankshaft position sensor seal (o-ring) with clean engine oil.

4. Install the NEW crankshaft position sensor seal (o-ring) onto the crankshaft position sensor.

2. Remove the clamps and water pump inlet hose.

5. Install the crankshaft position sensor until fully seated into the engine front cover.

6. Install the crankshaft position sensor bolt.

Tightening torque for crankshaft position bolt

.82 Kgf•m (71 lb ft) [8 N•m]

3.

4.

5.

6.

-74-

Remove the water pump bolts.

Remove the water pump.

Remove the water pump gaskets.

Discard the water pump gaskets.

Water Pump Clean and Inspect

Water Pump Installation Tools Required • J 41240 Fan Clutch Remover and Installer 1. If reusing the fasteners, apply sealant GM P/N 12346004 or equivalent to the threads of the water pump bolts.

2. Install the water pump and the NEW water pump gaskets.

3. Install the water pump bolts.

! CAUTION Refer to Safety Glasses Caution in Cautions and Notices.

1. Remove all the old gasket material from the water pump sealing surfaces.

2. Clean all the dirt and any debris from the water pump.

3. Inspect the water pump for the following: • Leakage or damage to the housing cover or gasket (1) • Excessive scratches or grouping to the gasket sealing surfaces (2) • Leakage from the water pump vent hole (3) A stain around the vent hole is acceptable. If leakage occurred (dripping) with the engine operating and the cooling system pressurized, then replace the water pump.

• Damaged bolt hole threads (4) • Excessive side-to-side movement of the water pump shaft (5) • Leakage around the water inlet pipe (6) • Leakage around the heater hose pipe (7) • Restrictions within the internal coolant passages

Tightening torque for water pump bolts

4.56 Kgf•m (33 lb ft) [45 N•m]

Important: After final assembly, the water pump inlet hose clamp tangs (water pump end) must point forward and the upper tang should be level with the outside diameter of the water pump inlet hose.

4. Install the water pump inlet hose and the water pump inlet hose clamps.

-75-

5. Install the fan and water pump pulley and bolts using the J 41240.

Tightening torque for water pump pulley bolts

2.497 Kgf•m (18 lb ft) [25 N•m]

-76-

Balancer and Camshaft Removal and Installation

1

2

3 12 13 9 11 7 10

5 4

6 Removal steps 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

8

-77-

Rod Guide Lifter Camshaft Gear Gear Kit Retainer Retainer Camshaft Balancer Bearing Kit - Camshaft Bearing Bearing Plug

Balance Shaft Removal

NOTE

Tools Required • J 23523-F Crankshaft Balancer Remover and Installer • J 38834 Balancer Shaft Bearing Service Kit 1. Remove the balance shaft drive gear. Inspect the sprockets for chipped teeth and wear. Worn sprockets will wear a new chain.

Important: The balance shaft drive and driven gears are serviced as a set. The set includes the balance shaft driven gear bolt.

5135

2. Remove the bolt and the balance shaft driven gear. Inspect the balance shaft drive and driven gears for nicks and burrs. a. Use a wrench in order to secure the balance shaft. Place the wrench onto the balance shaft near to the balance shaft front bearing. b. Remove the balance shaft bolt. c. Remove the wrench from the balance shaft 3. Remove the balance shaft driven gear from the balance shaft.

9847

5136

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c. Install the J 38834-1 into the J 26941. d. Slide the J 37734-2 and into the balance shaft bore of the engine block. e. Install the J 38834 bearing, washer and nut onto the J 38834-1. f. Using a wrench, secure the J 38834-1 and then rotate the J 37734 nut clockwise until the balance shaft rear bearing is removed from the engine block. g. Remove the J 26941 from the balance shaft rear bearing.

7. Discard the balance shaft rear bearing.

4. Remove the bolts and the balance shaft retainer.

J 38834-1 5137

NOTE Important: The balance shaft and the front bearing are serviced only as a package. Do not remove the front bearing from the balance shaft.

5. Use a soft-faced hammer to remove the balance shaft from the engine block.

J 38834-2

J 26941

5139

5139

6. Use the balancer shaft bearing service kit J 38834 and the crankshaft balancer remover and installer J 26941 in order to remove the balance shaft rear bearing. a. Install the crankshaft balancer remover and installer J 26941 legs behind the balance shaft rear bearing and secure. b. Install the balancer shaft bearing service kit J 38834 with the short threaded end through the balance shaft bore in the front of the engine block.

-79-

Camshaft Removal

Camshaft Bearing Removal

Tools Required • J23523-F Crankshaft Balancer Remover/Installer 1. Remove the camshaft retainer bolts and retainer.

Tools Required • J 33049 Camshaft Bearing Replacer

NOTE Important: A loose camshaft bearing may be caused by an enlarged, out-of-round or damaged engine block camshaft bearing bore.

NOTE Important: Always remove the camshaft inner bearings #2 and #3 first. The camshaft outer bearings #1 and #4 serve as a guide for the camshaft bearing replacer J 33049.

1. Select the cone (1), the handle (10), the expanding driver (4-8), the washer (2 or 3) and the expander assembly (15) from the J 33049 2. Assemble the J 33049.

5146

Notice: All camshaft journals are the same diameter, so care must be used in removing or installing the camshaft to avoid damage to the camshaft bearings.

2. Remove the camshaft. a. Install the three 6/16 x 4.0 inch bolts in the camshaft front bolt holes. b. Carefully rotate and pull the camshaft out of the bearings.

66100

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4. Remove the camshaft bearing replacer J 33049 from the engine block.

5. Remove the camshaft outer bearing #1 and #4. a. Insert the J 33049 into the camshaft outer bearing #1. b. Tighten the J 33049 expander assembly nut until snug. c. Drive the camshaft outer bearing #1 from the camshaft outer bearing bore #1. d. Loosen the J 33049 expander assembly nut. e. Remove the camshaft outer bearing #1 from the J 33049 expander assembly. f. Remove the J 33049 from the engine block. g. Insert the J 33049 expander assembly into the camshaft outer bearing #4. h. Tighten the J 33049 expander assembly nut until snug. i. Drive the camshaft outer bearing #4 from the camshaft inner bearing #4. j. Loosen the J 33049 expander assembly nut. k. Remove the camshaft outer bearing #4 from the J 33049 expander assembly.

6. Remove the camshaft bearing replacer J 33049 from the engine block.

7. Discard the camshaft bearings.

3. Remove the camshaft inner bearings #2 and #3. a. Insert the camshaft bearing replacer J 33049 through the front of the engine block and into the camshaft inner bearing #2. b. Tighten the J 3304) expander assembly nut until snug. c. Push the J 33049 guide cone into the camshaft front bearing in order to align the J 33049. d. Drive the camshaft inner bearing #2 from the camshaft inner bearing bore #2. e. Loosen the J 33049 expander assembly nut. f. Remove the camshaft inner bearing #2 from the J 33049 expander assembly. g. Insert the J 33049 expander assembly into the camshaft inner bearing #3. h. Tighten the J 33049 expander assembly nut until snug. i. Push the J 33049 guide cone into the camshaft front bearing in order to align the J 33049. j. Drive the camshaft inner bearing #3 from the camshaft inner bearing bore #3. k. Loosen the J 33049 expander assembly nut. l. Remove the camshaft inner bearing #3 from the J 33049 expander assembly.

J 33049

J 33049

4985

63219

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Camshaft and Bearings Clean and Inspect

7. Measure the engine camshaft journals with a micrometer. If the camshaft journals are more than 0.025 mm (0.0010 in) out-of-round, then replace the engine camshaft.

Tools Required • J 7872 Magnetic Base Indicator Set 1. Clean the engine camshaft in cleaning solvent.

2. Dry the engine camshaft with compressed air.

3. Inspect the camshaft retainer plate for damage.

If the camshaft retainer plate is damaged, replace as necessary.

4. Inspect the camshaft bearings for correct fit into the engine block camshaft bearings bores.

The camshaft bearings have an interference fit to the engine block camshaft bearing bores and must not be loose in the engine block camshaft bearing bores.

188014

8. Measure for a bent engine camshaft or excessive engine camshaft run out using the magnetic base indicator J7872.

• Mount the engine camshaft in a suitable stand between centers.

• Use the magnetic base indicator J7872 to check the intermediate engine camshaft journals.

9. Measure the engine camshaft lobe lift using the magnetic base indicator J7872.

• Place the engine camshaft on the V-blocks.

• Use the magnetic base indicator J7872 to measure the engine camshaft lobe lift.

10. Replace the engine camshaft if the engine camshaft lobe lift is not within specifications.

Refer to General Specifications.

334499

NOTE Important: If any camshaft bearing is excessively worn or scored, replace all the camshaft bearings.

5. Inspect the camshaft bearings for excessive wear or scoring.

6. Inspect the engine camshaft for the following: • Worn, scored or damaged bearing journals (1) • Worn engine camshaft lobes (2) • Damaged bolt hole threads (3) • Damaged camshaft sprocket locator pin (4)

188095

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Camshaft Bearing Installation

NOTE

Tools Required • J 33049 Camshaft Bearing Service Kit

Important: The camshaft bearings vary in size.

When ordering the new camshaft bearings, be sure to order the correct camshaft bearings for the application to be serviced.

Always install the camshaft outer bearings #1 and #4 first. The camshaft outer bearings serve as a guide for the camshaft bearing service kit J 33049 and help center the camshaft inner bearings during the installation process.

NOTE Important: When installing the camshaft bearings, always make sure that the camshaft bearing lubrication hole is located above the 3 o’clock position (1) or the 9 o’clock position (2). The proper positioning of the camshaft bearing lubrication hole is in order to ensure the best lubrication of the engine camshaft journals.

3. Install the NEW camshaft outer bearings #4 and #1. a. Install the NEW camshaft outer bearing #4 onto the J33049 expander assembly. b. Tighten the J 33049 expander assembly nut until snug. c. Align the lubrication hole of the camshaft outer bearing #4 above the 3 o’clock position or the 9 o’clock position of the camshaft outer bearing bore #4 at the rear of the engine block. d. Drive the camshaft outer bearing #4 into the camshaft outer bearing bore #4 at the rear of the engine block. e. Loosen the J 33049 expander assembly nut. f. Remove the camshaft outer bearing #4 from the J 33049 expander assembly. g. Install the NEW camshaft outer bearing #1 onto the J33049 expander assembly. h. Tighten the J 33049 expander assembly nut until snug. i. Align the lubrication hole of the camshaft outer bearing #1 above the 3 o’clock position or the 9 o’clock position of the camshaft outer bearing bore #1 at the front of the engine block. j. Drive the camshaft outer bearing #1 into the camshaft outer bearing bore #1 at the front of the engine block. k. Loosen the J 33049 expander assembly nut. l. Carefully slide the J 33049 into the engine block until the J 33049 expander assembly is positioned between the camshaft inner bearing bores.

594647

1. Select the handle (10), the expanding driver (4-8), the washer (2 or 3) and the expander assembly (15) from the camshaft bearing service kit J 33049.

2. Assemble the camshaft bearing service kit J 33049.

66100

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g. Install the NEW camshaft inner bearing #2 onto the J33049 expander assembly. h. Tighten the J 33049 expander assembly nut until snug. i. Align the lubrication hole of the camshaft inner bearing #2 above the 3 o’clock position or the 9 o’clock position of the camshaft inner bearing bore #2 of the engine block. j. Push the J 33049 guide cone into the camshaft front bearing bore #1 in order to align the J 33049. k. Drive the camshaft inner bearing #2 into the camshaft inner bearing bore #2 of the engine block. l. Loosen the J 33049 expander assembly nut.

5. Carefully remove the J 33049 from the engine block.

6. Install a new camshaft rear bearing hole plug. Coat the outside diameter of the plug with MCF P/N 2I4256 (GM P/N 12346004) sealant or equivalent. a. Install the plug flush to 0.80 mm (1/32 in.) b. Install the plug while RTV is still wet.

J 33049 63219

J 33049

Camshaft Installation 1. Apply clean engine oil or equivalent, to the following components: • The engine camshaft lobes • The camshaft bearing journals • The camshaft bearings 2. Install three 5/16-18 x 4.0 in. bolts into the engine camshaft front bolt holes.

4985

4. Install the NEW camshaft inner bearings #3 and #2. a. Install the NEW camshaft inner bearing #3 onto the J33049 expander assembly. b. Align the lubrication hole of the camshaft inner bearing #3 above the 3 o’clock position or the 9 o’clock position of the camshaft inner bearing bore #3 of the engine block. c. Push the J 33049 guide cone into the camshaft front bearing bore #1 in order to align the J 33049. d. Drive the camshaft inner bearing #3 into the camshaft inner bearing bore #3 of the engine block. e. Loosen the J 33049 expander assembly nut. f. Carefully slide the J 33049 until the J33049 expander assembly is positioned between the camshaft inner bearing bore #2 and the camshaft outer bearing bore #1.

NOTE Important: All camshaft journals are the same diameter, so care must be used in removing or installing the camshaft to avoid damage to the camshaft

5147

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Balance Shaft Clean and Inspect

3. Use the bolts as a handle in order to install the engine camshaft.

4. Remove the 3 bolts from the front of the engine camshaft.

5. If reusing the fasteners, apply thread lock GM P/N 12345382 or equivalent to the threads of the camshaft retainer bolts.

6. Install the camshaft retainer and bolts.

Important: The balance shaft and the balance shaft front bearing are serviced only as an assembly. Do not remove the balance shaft front bearing from the balance shaft.

188106

1. Clean the following components in cleaning solvent.

• The balance shaft (1) • The balance shaft retainer (2) • The balance shaft rear bearing • The balance shaft driven gear (4) • The balance shaft drive gear 2. Dry the following components with compressed air.

• The balance shaft (1) • The balance shaft retainer (2) • The balance shaft rear bearing • The balance shaft driven gear (4) • The balance shaft drive gear 3. Inspect the balance shaft bearings for the following: • Front ball bearing for damage or wear • Front ball bearing for smoothness of operation • Rear sleeve bearing for wear, scoring or other damage.

4. Inspect the balance shaft (1) for the following: • Wear or scoring on the rear bearing journal • Damaged bolt hole threads • Damage to the balance shaft driven gear locator pin 5. Inspect the balance shaft retainer (2) for wear or damage 6. Inspect the balance shaft retainer bolts (3) for damaged threads.

7. Inspect the driven gear (4) for the following: • Excessive wear or damage • Nicks, burns or scoring

188030

Tightening torque for Camshaft 1.22Kgf•m (106 lb•in) [12N•m] Retainer bolts

-85-

8. Inspect the driven gear bolt (5) for damaged threads.

9. Inspect the balance shaft drive gear for the following: • Excessive wear or damage • Nicks, burns or scoring

2. Remove the J 38834.

J 38834-1 J 38834-3

J 38834-2 340085

Balance Shaft Installation

9848

Tools Required • J 36996 Balance Shaft Installer.

• J 8092 Universal Driver Handle.

• J 36660 Torque / Angle Meter.

Important: The balance shaft and the balance shaft front bearing are serviced only as an assembly. Do not remove the balance shaft front bearing from the balance shaft.

1. Apply clean engine oil or equivalent to the balance shaft front bearing.

2. Use the balance shaft installer J 36996 and the universal drive handle J 8092 in order to install the balance shaft.

Balance Shaft Bearing and/or Bushing Installation Tools Required • J 38834 Balance Shaft Service Kit 1. Use the J 38834 in order to install the balance shaft rear bearing. a. Install the J 38834-3 onto the short threaded end of the J 38834-1. b. Install the J 38834 nut, the washer and the bearing on the long threaded end of the J 38834-1. c. Install the J 38834-2 onto the J 38834-1 so that the smaller diameter of the J 38834-2 will be facing the front of the engine block. d. Install the J 38834-2 on the inside of the balance shaft front bearing bore. e. Lubricate the NEW balance shaft rear bearing with clean engine oil. f. Install the balance shaft rear bearing onto the J 38834-2. g. Align the balance shaft rear bearing for installation. h. Using a wrench, secure the J 38834- into place. i. Rotate the J 38834 until the balance shaft rear bearing is properly and completely pushed into the balance shaft rear bearing bore.

J 8092

J 36996 5141

-86-

3. Install the balance shaft retainer and bolts.

7. Remove the wrench from the balance shaft.

8. Rotate the balance shaft by hand in order to ensure that there is clearance between the balance shaft and the valve lifter pushrod guide.

If the balance shaft does not rotate freely, check to ensure that the retaining ring on the balance shaft front bearing is seated on the case.

Tightening Torque for Balance 1.22Kgf•m (106 lb•in) [12N•m] Shaft bolts

188031 5136

4. Install the balance shaft driven onto the balance shaft.

5. If reusing the fastener, apply thread lock MCF P/N 2I4264, GM P/N 12345382 or equivalent to the threads of the balance shaft driven gear bolt.

6. Install the balance shaft driven gear bolt. a. Use a wrench to secure the balance shaft. b. Place the wrench onto the balance shaft near to the balance shaft front bearing. c. Install the balance shaft driven gear bolt.

Tightening Torque for Balance Shaft Driven gear bolt First Pass

2.08 Kgf•m (15 lb ft) [20N•m]

Tightening Torque for Balance Shaft Driven gear bolt Final Pass

35°

9. Install the balance shaft drive gear. DO NOT install the camshaft sprocket bolts at this time.

9847

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10. Rotate the engine camshaft so that the timing mark on the balance shaft drive gear is in the 12 o’clock position.

12. Rotate the balance shaft so that the timing mark on the balance shaft driven gear is in the 6 o’clock position.

9848 9849

11. Remove the balance shaft drive gear.

13. Position the balance shaft drive gear onto the engine camshaft.

14. Look to ensure that the balance shaft drive gear and the balance shaft driven gear timing marks are aligned.

9847

5144

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Crankshaft, Flywheel, Rear Seal, and Bearings Removal and Installation

Removal Steps 1. Bolt 2. Bushing - Flywheel 3. Flywheel Assy 4. Housing 5. Seal 6. Gasket 7. Hub 8. Bolt 9. Balancer 10. Crankshaft Bearing Cap 11. Lower Bearing Kit 12. Crankshaft 13. Upper Bearing Kit

-89-

Crankshaft Rear Oil Seal and Housing Removal

Engine Flywheel Removal 1. Remove the flywheel bolts.

2. Remove the flywheel.

1. Remove the crankshaft rear oil seal housing nuts and bolts.

2. Remove the crankshaft rear oil seal housing, seal, and gasket.

4078

Engine Flywheel Clean and Inspect 1. Clean the engine flywheel in cleaning solvent.

2. Dry the engine flywheel with compressed air.

3. Inspect the engine flywheel for the following: • Stress cracks around the engine flywheel-totorque converter bolt hole locations (1) • Missing balance weights • Stress cracks around the engine flywheel-tocrankshaft bolt hole locations (2) or (3)

11479

3. Remove the crankshaft rear oil seal from the crankshaft rear oil seal housing. Insert a screw driver into the notches provided in the rear seal retainer and pry out the seal.

4. Discard the crankshaft oil seal.

NOTE Important: Do not attempt to repair the welded areas (if present) that retain the ring gear to the engine flywheel plate. Always install a NEW engine flywheel.

• Welded areas that retain the ring gear onto the engine flywheel for cracking (4) (if present) • Damaged ring gear teeth (5)

31379

381965

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5. Remove the crankshaft bearings from the crankshaft bearing caps

Crankshaft and Bearings Removal 1. Mark or Identify the crankshaft bearing cap locations, direction and positions for assembly.

2. Remove the crankshaft bearing cap bolts.

3. Remove the crankshaft bearing caps.

334342

6. Remove the crankshaft bearings from the engine block.

334329

4. Remove the crankshaft.

334338

Crankshaft and Bearings Clean and Inspect Tools Required • J 7872 Magnetic Base Dial Indicator • J 36660 Electronic Torque Angle Meter

334336

! CAUTION Safety glasses must be worn or eye injury may occur.

-91-

Important: Use care when handling the crankshaft.

Avoid damage to the crankshaft bearing surfaces.

1. Clean the crankshaft in cleaning solvent.

Remove all sludge or restrictions from the oil passages.

2. Dry the crankshaft with compressed air.

5. Inspect the crankshaft for the following: • Crankshaft journals (1) should be smooth with no evidence of scoring or damage.

• Deep grooves (2) • Scratches or uneven wear (3) • Pitted surfaces (4) • Wear or damage to the thrust journal surfaces • Scoring or damage to the rear seal surface • Restrictions to the oil passages • Damage to the threaded bolt holes

334383

156170

3. Clean the crankshaft bearings in cleaning solvent.

Wipe the crankshaft bearings clean with a soft cloth, do not scratch the crankshaft bearing surface.

4. Dry the crankshaft bearings with compressed air.

6. Inspect the crankshaft balancer key (1), the keyway (2) and the threaded hole (3) for damage. Repair or replace the crankshaft as necessary.

188090

7. Measure the crankpins for out-of-round and taper. Refer General Specifications.

334386

188015

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8. Use a suitable support to support the crankshaft on the front and rear journals.

9. Use the magnetic dial indicator J 7872 to measure the crankshaft journal run out. The crankshaft run out should not exceed 0.025 mm (0.0010 in).

188467

11. Inspect the crankshaft bearings for craters or pockets. Flattened sections on the crankshaft bearing halves also indicate fatigue.

35210

10. Measure the crankshaft end play.

Important: In order to properly measure the crankshaft end play, the crankshaft, the crankshaft bearings and the crankshaft bearing caps, the crankshaft bearing cap bolts must be installed into the engine block and the bolts tightened to specifications.

• Firmly thrust the crankshaft first rearward, then forward. This will align the crankshaft rear bearings and the crankshaft thrust surfaces.

• With the crankshaft pushed forward, insert a feeler gauge between the crankshaft and the crankshaft bearing surface and then measure the clearance. Refer to General Specifications.

• If the correct end play cannot be obtained, verify that the correct size crankshaft bearing has been installed. Refer to General Specifications.

• Inspect the crankshaft for binding. Turn the crankshaft to check for binding. If the crankshaft does not turn freely, then loosen the crankshaft bearing cap bolts, one bearing cap at a time, until the tight crankshaft bearing is located.

52051

12. Inspect the crankshaft bearings for excessive scoring or discoloration.

13. Inspect the crankshaft bearings for dirt or debris imbedded into the crankshaft bearing material.

52053

14. Inspect the crankshaft bearings for improper seating indicated by bright, polished sections of the crankshaft bearings.

• If the lower half of the crankshaft bearing is worn or damaged, both the upper and lower halves of the crankshaft bearing should be replaced.

• Generally, if the lower half of the crankshaft bearing is suitable for use, the upper half of the crankshaft bearing should also be suitable for use.

Burrs on the crankshaft bearing cap, foreign matter between the crankshaft bearing and the engine block or crankshaft bearing cap or a faulty crankshaft bearing could cause a lack of clearance at the crankshaft bearing.

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Service Prior to Assembly

5. Install the crankshaft bearings into the crankshaft bearing caps.

6. Apply clean engine oil to the crankshaft bearings.

Dirt will cause premature wear of the rebuilt engine.

During assembly, lubricate all moving parts lightly with engine oil or engine assembly lubricant (unless otherwise specified.) This will provide initial lubrication when the engine is started.

Crankshaft and Bearings Installation Tools Required • J 36660 Electronic Torque Angle Meter 1. Install the crankshaft bearings into the engine block.

2. Apply clean engine oil to the crankshaft bearings.

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7. Install the crankshaft bearing caps in the original position and with the arrow on the crankshaft bearing caps in the direction of the front of the engine block.

8. Install the crankshaft bearing cap bolts until snug.

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3. Apply clean engine oil to the crankshaft bearing journals.

4. Install the crankshaft.

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9. Thrust the crankshaft rearward in order to set and align the crankshaft thrust bearings and the crankshaft bearing caps.

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10. Thrust the crankshaft forward in order to align the rear faces of the crankshaft thrust bearings.

11. Tighten the crankshaft bearing cap bolts. a. Tighten the crankshaft bearing cap bolts to 2.08 Kgf•m (15 lb•ft) [20N•m] on the first pass. b. Tighten the crankshaft bearing cap bolts on the final pass an additional 73 degrees using the electronic torque angle meter J 36660.

Tightening torque for Crankshaft Bearing Cap Bolts

• In order to determine the correct replacement

1st pass 2.08 Kgf•m (15 lb•ft) [20N•m] Final pass 73 degrees

•

12. Measure the crankshaft end play. a. Firmly thrust the crankshaft rearward, and then forward. This will align the crankshaft rear bearing thrust surfaces. b. With the crankshaft pushed forward, insert a feeler gauge between the crankshaft and the crankshaft rear bearing thrust surface to measure the clearance.

•

Specification Crankshaft end play 0.05-0.20 mm (0.002-0.008 in) 13. Rotate the crankshaft in order to check for binding. A bent crankshaft or lack of proper crankshaft bearing clearance may cause binding.

14. If the crankshaft does not turn freely, loosen the crankshaft bearing cap bolts on 1 crankshaft bearing cap at a time in order to determine the location of the binding. A lack of proper crankshaft bearing clearance may be caused by the following: • Burrs on the crankshaft bearing cap • Foreign material between the crankshaft bearing and the engine block • Foreign material between the crankshaft bearing and the crankshaft bearing cap • Damaged crankshaft bearing • Improper size crankshaft bearing

•

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Micrometer Method for Crankshaft Bearings 1. Measure the crankshaft journal diameter with a micrometer in several places, approximately 90 degrees apart, and then average the measurements.

2. Determine the taper and the out-of-round of the crankshaft journal. Refer to General Specifications.

3. Install the crankshaft bearings into the engine block or connecting rod assembly.

Measure Crankshaft Bearing Clearances • The crankshaft bearings are of the precision

•

crankshaft bearing size, the crankshaft bearing clearance must be measured accurately.

Either the micrometer or plastic gauge method may be used; however, the micrometer method gives more reliable results and is preferred. When checking connecting rod bearing clearances, the plastic gauge method will result in unreliable measurements. The use of J 43690 is preferred.

Normally the crankshaft bearing journals wear evenly and are not out-of-round. However, if a crankshaft bearing is being fitted to an outof-round crankshaft bearing journal, be sure to fit to the maximum diameter of the crankshaft bearing journal. If the crankshaft bearing is fitted to the minimum diameter and the crankshaft bearing journal will result in rapid crankshaft bearing failure.

If the crankshaft bearing clearance is within specifications, the crankshaft bearing is satisfactory. If the clearance is not within specifications, replace the crankshaft bearings.

Always replace both the upper and lower crankshaft bearings as a set.

A standard or oversize crankshaft bearing combination may result in the proper clearance.

If the proper crankshaft bearing clearance cannot be achieved using the standard or the undersize crankshaft bearings, it may be necessary to repair or replace the crankshaft.

insert type and do not use shims for adjustment. If the clearances are excessive, then new upper and lower crankshaft bearings will be required. The service crankshaft bearings are available in the standard size and an undersize.

The selective fitting of the crankshaft bearings are necessary in production in order to obtain close tolerances. For this reason, in one journal bore you may use one-half of a standard crankshaft bearing with one-half of a undersize crankshaft bearing.

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4. Install the bearing cap bolts and tighten to specifications.

10. If the crankshaft bearing clearances exceeds specifications, install new crankshaft bearings as follows: a. Measure the crankshaft bearing inside diameter (ID) at the top and the bottom using an inside micrometer. b. Compare the crankshaft bearing clearance to the specifications. Refer to General Specifications.

11. Replace or repair the crankshaft if the proper clearances cannot be obtained.

Micrometer Method for Connecting Rod Bearings Important: Do not shim, scrape or file bearing inserts. Do not touch the bearing surface of the insert with bare fingers. Skin oil and acids will etch the bearing surface.

1. Measure the crankpin diameter with a micrometer in several places, approximately 90 degrees apart, and then average the measurements.

2. Determine the taper and the out-of-round. Refer to General Specifications.

3. Install the connecting rod bearings into the connecting rod cap and the connecting rod.

4. Install the connecting rod caps and the nuts and tighten to the specified torque by a two step method. Torque all nuts to the specified torque on the first pass. Tighten the nuts on the final pass an additional 70 degrees using the electronic torque angle meter J-36660.

353070

5. Install the crankshaft bearing caps in the original positions and with the arrow on the crankshaft bearing caps in the direction of the front of the engine block.

6. Install the crankshaft bearing cap bolts and tighten to the specified torque using a two step method.

Tightening torque for Crankshaft Bearing Cap bolts First Pass

2.08 Kgf•m (15 lb ft) [20 N•m]

Tightening torque for Crankshaft Bearing Cap bolts Final Pass

Additional 73°

7.

8.

9.

Tightening torque for Connecting 2.77 Kgf•m Rod Cap Nuts First Pass (20 lb ft) [27 N•m]

Measure the bearing inside diameter (ID) at two points 90 degrees apart.

In order to determine the crankshaft bearing clearance, subtract the average journal diameter from the average bearing inside diameter.

Compare the crankshaft bearing clearance to the specifications. Refer to General Specifications.

Tightening torque for Connecting Rod Cap Nuts Final Pass

Additional 70°

5. Measure the connecting rod bearing inside diameter (ID) at the top and the bottom using an inside micrometer.

6. Compare the connecting rod bearing clearance to the specifications. Refer to General Specifications.

7. If the connecting rod bearing clearance is within specifications, the connecting rod bearing is satisfactory.

• Replace the connecting rod bearing if the clearance is not within specifications.

• Always replace both the upper and the lower connecting rod bearings as an assembly.

8. A standard or undersize connecting rod bearing combination may result in the proper clearance.

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If the proper connecting rod bearing clearance cannot be achieved using the standard or the undersize connecting rod bearings, it will be necessary to replace or repair the crankshaft.

Measuring Connecting Rod Bearing Clearances J43690 Method

5. Install the foot (1) and bolt (2) to the pivot arm assembly (3). Tighten the bolt until snug.

1. Remove the oil pan and other necessary components to gain access to the connecting rods.

Remove the oil pump, screen and deflector (when applicable).

2. Rotate the crankshaft until the crankshaft journal/connecting rod to be measured is in the 10 o’clock position.

Important: The crankshaft must be secure with no movement or rotation in order to obtain an accurate reading. Remove an intermediate bearing cap (as required) in order to secure the crankshaft and allow measurement of connecting rod bearing clearances.

3. Remove the bearing cap bolts (1), cap (2) and bearing half.

Notice: Refer to Fastener Notice in Cautions and Notices.

4. Insert a piece of paper card stock onto the crankshaft journal. Install the bearing half, bearing cap and bolts. Refer to Fastener Tightening Specifications.

6. Install the screw (1 or 3) to the pivot arm assembly (2).

7. Install the pivot arm assembly (1) onto the connecting rod.

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8. Position the foot of the pivot arm assembly over the large end of the connecting rod bolt.

9. Position the screw (1) onto the small end of the connecting rod bolt and tighten securely.

11. Align the center of the base (1) with the screw (3) of the pivot arm assembly. Tighten the bolt (2) until snug.

12. Align the link (1) of the pivot arm assembly on a plane (3) equal to that of the connecting rod beam (2).

10. Install the base (1) and bolt (2) to the oil pan rail.

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13. With the link of the pivot arm assembly aligned to the beam of the connecting rod, position the pivot arm to the base and insert the pin (1).

Important: The clamp of the swivel base and the shaft of the indicator should be free of oil or other debris. A loose or improperly clamped indicator may indicate incorrect readings.

16. Install the indicator (2) to the swivel base (1).

Tighten the clamp of the baser until snug.

14. Install the handle (1) to the pivot arm assembly.

17.

15. Select the adapter (2) (as required) and install to the swivel base (1). Tighten until snug.

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Install the swivel base (1) to the oil pan rail of the engine block. Tighten until snug.

18. Adjust the swivel base as required and position the indicator tip slightly above the connecting rod cap. Lock the swivel base in position by rotating the locking lever (1). Do not allow the tip of the indicator to contact the connecting rod at this time.

21. Lightly actuate the handle of the pivot arm assembly (multiple items in both directions) to ensure the oil film is removed from the journal.

19. The tip of the indicator should be positioned above and NOT in contact with the cap end of the connecting rod.

22.

Load the handle in the forward position and zero the dial indicator. Load the handle multiple times in both directions and record the reading.

Important: During this procedure, card stock may enter the crankshaft journal oil galleries. Be sure to remove all card stock from the bearing journal and oil galleries prior to reassembly.

23.

24.

20. Rotate the fine adjustment knobs on the dial indicator end of the swivel base to position the tip of the indicator in contact with the connecting rod.

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Remove the bearing cap bolts, cap and paper stock.

Replace the bearing halves as required to obtain the proper bearing clearance.

Plastic Gauge Method for Crankshaft Bearings

4. Install the crankshaft bearings into the crankshaft bearing caps.

1. Install the crankshaft bearings into the engine block.

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5. Install the crankshaft bearing caps in the original positions and with the arrow on the crankshaft bearing caps in the direction of the front of the engine block.

6. Install the crankshaft bearing cap bolts and tighten in a two step method. First pass tighten to the specified torque and the final pass tighten an additional 73 degrees using the electronic torque angle meter J 36660.

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2. Install the crankshaft.

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3. Install the gauging plastic the full width of the journal.

Tightening Torque for Crankshaft Bearing Cap Bolts First Pass

2.08 Kgf•m (15 lb ft) [20 N•m]

Tightening Torque for Crankshaft Bearing Cap Bolts Final Pass

Additional 73°

7. Remove the crankshaft bearing cap bolts.

8. Remove the crankshaft bearing caps. The gauging plastic may adhere to either the crankshaft bearing journal or the crankshaft bearing surface.

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9. Without removing the gauging plastic, measure the compressed width at the widest point using the graduated scale on the edge of the gauging plastic envelope.

If the flattened gauging plastic tapers toward the middle or the ends, there may be a difference in clearance indicating taper, low spot or other irregularity of the crankshaft bearing or the crankshaft bearing journal.

• Normally the crankshaft bearing journals wear evenly and are not out-of-round. However, if a crankshaft bearing is being fitted to an outof-round 0.0254 mm (0.0010 in) (maximum) crankshaft bearing journal, be sure to fit to the maximum diameter of the crankshaft bearing journal. If the crankshaft bearing is fitted to the minimum diameter and the crankshaft bearing journal is excessively outof-round, the interference between the crankshaft bearing and the crankshaft bearing journal will result in rapid crankshaft bearing failure.

• If the crankshaft bearing clearance is within specifications, the crankshaft bearing is satisfactory. If the clearance is not within specifications, replace the crankshaft bearing.

Connecting Rod Side Clearance Measuring Procedure

Always replace both the upper and lower crankshaft bearings as a unit.

• A standard or undersize crankshaft bearing combination may result in the proper clearance. If the proper crankshaft bearing clearance cannot be achieved using the standard or the undersize crankshaft bearings, it may be necessary to repair or replace the crankshaft.

Important: Do not shim, scrape or file bearing inserts. Do not touch the bearing surface of the insert with bare fingers. Skin oil and acids will etch the bearing surface.

Crankshaft Balancer Clean and Inspect

1. Insert a feeler gauge between the connecting rod caps and measure the connecting rod side clearance. Refer to General Specifications.

2. Connecting rod side clearances may also be measured with a dial indicator set.

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! CAUTION Refer to Safety Glasses Caution in Cautions and Notices.

1. Clean the crankshaft balancer in cleaning solvent.

2. Dry the crankshaft balancer with compressed air.

3. Inspect the crankshaft balancer for the following: • Loose or improperly installed front groove pin (1) (crankshaft balancer) A properly installed front groove pin should be installed until flush or below flush with the face of the crankshaft balancer.

Important: A crankshaft front oil sealing surface with excessive scoring, grooves, rust or other damage must be replaced.

• Worn, grooved or damaged crankshaft front oil sealing surface (2) Minor imperfections on the crankshaft balancer crankshaft front oil seal surface may be removed with a polishing compound or fine grade emery cloth.

• Worn, chunking or deteriorated rubber (3) between the hub and the outer ring • Worn or damaged keyway (4) • Worn or damaged bolt hole threads (5)

10. Remove the flattened gauging plastic.

11. Measure the remaining crankshaft bearing journals.

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Important: Always use a NEW crankshaft rear oil seal housing gasket when installing the crankshaft rear oil seal housing.

2. Install the NEW crankshaft rear oil seal housing gasket.

Crankshaft Rear Oil Seal and Housing Installation Tools Required • J 35621-B Rear Main Seal Installer Notice: Refer to Fastener Notices in Cautions and Notices.

1. Install the crankshaft rear oil seal housing retainer stud.

Tightening torque for crankshaft rear oil seal housing retainer stud

3. Install the crankshaft rear oil seal housing onto the crankshaft rear oil seal housing retainer stud.

4. Install the crankshaft rear oil seal housing nut and bolts.

Tightening torque for crankshaft rear oil seal housing nut and bolts

1.22 Kgf•m (53 lb ft) [6 N•m]

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1.22 Kgf•m (106 lb ft) [12 N•m]

5. Apply a small amount (2 to 3 drops) of clean engine oil to the bore of the crankshaft rear oil seal housing.

6. Apply a small amount (2 to 3 drops) of clean engine oil to the outside diameter of the engine flywheel pilot flange.

7. Apply a small amount (1 drop) of clean engine oil to the outside diameter of the flywheel locator pin.

8. Apply a small amount (2 to 3 drops) of clean engine oil to the crankshaft seal surface.

9. Inspect the J 35621-B flange for imperfections that may damage the crankshaft rear oil seal.

Minor imperfections may be removed with a fine grade emery cloth.

Important: DO NOT allow oil or any other lubricants to contact the seal lip of the crankshaft rear oil seal.

14. Install the crankshaft rear oil seal onto the crankshaft and into the crankshaft rear oil seal housing. a. Turn the J 35621-B wing nut clockwise until the crankshaft rear oil seal is installed near to flush and square to the crankshaft rear oil seal housing.

Increased resistance will be felt when the crankshaft rear oil seal has reached the bottom of the crankshaft rear oil seal housing bore. b. Turn the J 35621-B wing nut counterclockwise to release the J 35621-B from the crankshaft rear oil seal.

15. Remove the J 35621-B from the crankshaft.

16. Wipe off any excess engine oil with a clean rag.

Engine Flywheel Clean and Inspect

! CAUTION Refer to Safety Glasses Caution in Cautions and Notices.

1. Clean the engine flywheel(1) or (2) in cleaning solvent.

2. Dry the engine flywheel with compressed air.

10. Remove the sleeve from the crankshaft rear oil seal.

11. Apply a small amount (2 to 3 drops) of clean engine oil to the outside diameter of the crankshaft rear oil seal.

12. Install the crankshaft rear oil seal onto the J 35621-B. 13. Install the J 35621-B onto the rear of the crankshaft and hand tighten the tool bolts until snug.

Notice: Proper alignment of the crankshaft rear oil seal is critical. Install the crankshaft rear oil seal near to flush and square to the crankshaft rear oil seal housing. Failing to do so may cause the crankshaft rear oil seal or the crankshaft rear oil seal installation tool to fail.

3. Inspect the engine flywheel (automatic transmission) (if equipped) for the following: • Stress cracks around the engine flywheelto-torque converter bolt hole locations (1) • Missing balance weights • Stress cracks around the engine flywheelto-crankshaft bolt hole locations (2) or (3)

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Important: Do not attempt to repair the welded areas (if present) that retain the ring gear to the engine flywheel plate. Always install a NEW engine flywheel.

• Welded areas that retain the ring gear onto the engine flywheel for cracking (4) (if present).

• Damaged ring gear teeth (5)

5. Inspect the engine flywheel (manual transmission) (if equipped) for the following: • Pitted friction surface (1) • Scoring or grooves (2) • Damaged ring gear teeth (4) • Loose or improperly positioned ring gear The ring gear has an interference fit onto the engine flywheel and the ring gear should be positioned completely flat against the flange of the engine flywheel.

4. Inspect the engine flywheel (manual transmission) (if equipped) for loose or improperly installed flywheel weights (if applicable).

A properly installed flywheel weight should be installed until flush or below flush with the face of the engine flywheel.

Engine Flywheel Installation 1. Install the engine flywheel to crankshaft.

2. Align the locator hole to the pin.

3. Install the engine flywheel bolts.

Tightening torque for engine 10.25 Kgf•m (74 lb•ft) [100 N•m] flywheel bolts

4078

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Clutch Pilot Bearing Installation

! CAUTION Refer to Safety Glasses Caution in Cautions and Notices.

1. Install the NEW clutch pilot bearing using a suitable clutch pilot bearing installation tool.

2. Measure to ensure the proper installation depth is obtained.

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Cylinder Block Cleaning and Inspection

Disassembly steps 1. Engine support (R.H.) 2. Engine support (L.H.) 3. Cylinder block

7EN0035

-107-

Engine Block Plug Removal

3. Remove the engine oil pressure sensor fitting.

Tools Required • J 41712 Oil Pressure Switch Socket 1. Remove the knock sensor from the engine block.

188020

4. Remove the dowel straight pins (transmission locator) (if required).

10793

2. Remove the engine oil pressure gauge sensor using the oil pressure switch socket J41712.

334350

5. Remove the engine block left side oil gallery plug.

6. Remove the engine block left rear oil gallery plug.

7. Remove the engine block right rear oil gallery plug.

J 41712

188018

5271

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8. Remove the expansion cup plug (camshaft rear bearing hole) and discard.

10. Remove the spring type S pin (crankshaft rear oil seal housing locator) (if required).

334323

11. Remove the front oil gallery plugs or balls from the front of the engine block and discard.

12. Insert a 3/8 x 26 in. rod into the rear oil gallery holes in order to drive out the front oil gallery plugs or balls.

334364

9. Remove the expansion cup plug (balance shaft rear bearing hole) and discard.

5270

13. Remove the engine block core hole plugs. a. Use a suitable tool in order to drive the engine block core hole plugs into the coolant jacket. b. Use a suitable tool in order to pull the engine block core hole plugs from the coolant jacket. c. Discard the engine block core hole plugs.

334366

480550

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14. Remove the oil filter bypass valve and discard.

1. Clean all the remaining sealing or gasket material from the sealing surfaces.

2. Clean the engine block with cleaning solvent.

3. Flush the engine block with clean water or steam.

4. Clean the cylinder bores.

5. Clean the oil galleries and the oil passages.

6. Clean the scale and the deposits from the coolant passages.

Notice: Clean all debris, dirt and coolant from the engine block cylinder head bolt holes. Failure to remove all foreign material may result in damaged threads, improperly tightened fasteners or damage to the components.

7. Clean the engine block cylinder head bolt holes.

8. After cleaning the engine block, spray or wipe the cylinder bores and the machined surfaces with clean engine oil.

9. Inspect the following areas: • Coolant jackets (1) for cracks • Cylinder bores (2) for scratches or gouging • Valve lifter bores (3) for excessive scoring or wear • Threaded holes (4) for damage • Crankshaft bearing webs (5) for cracks • Crankshaft bearing caps (6) and the crankshaft bearing bores (7) for damage ■ The crankshaft bearing bores should be round and uniform when measuring the inside diameter (ID).

■ The surface where the crankshaft bearings contact the crankshaft bearing bore should be smooth.

■ If a crankshaft bearing cap is damaged and requires replacement, replace the crankshaft bearing cap first, then rebore the engine block crankshaft bearing bores and check for proper alignment. Finally, check the crankshaft for the proper clearances.

• Engine block core hole plug bores (8) for damage • Engine block (9) for cracks or damage • Engine mount bosses (10) for damage 10. Measure the cylinder bores for taper and out-ofround. a. Depress the plunger on the cylinder bore guage J 8087 7 mm (0.275 in) or until the J 8087 enters the cylinder bore. b. Center the cylinder bore guage J 8087 in the cylinder bore and turn the indicator dial to 0. c. Move the cylinder bore guage J 8087 up and down the cylinder bore to determine the cylinder bore taper. Refer to General Specifications. d. Turn the J8087 to different points around the cylinder bore to determine the cylinder bore out-of-round condition. Refer to Engine Mechanical Specifications.

188026

Engine Block Clean and Inspect Tools Required • J 8087 Cylinder Bore Gauge

! CAUTION Safety Glasses must be worn or eye injury may occur.

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Cylinder Boring and Honing Honing Procedure 1. When honing the cylinder bores, follow the manufacturer’s recommendations for equipment use, cleaning and lubrication.

• Use only clean sharp stones of the proper grade for the amount of material to be removed.

• Dull, dirty stones cut unevenly and generate excessive heat.

• DO NOT hone to a final grade with a coarse or medium- grade stone.

• Leave sufficient metal so that all the stone marks will be remove with the fine grade stones.

• Perform the final honing with a fine-grade stone and hone the cylinder bore in a crosshatch pattern at 45-65 degrees to obtain the proper clearance.

J 8087

NOTE Caution: Do not grind the mating surfaces of the cylinder block and cylinder head beyond 0.2 mm (0.008 in.) of total grinding limit.

186747

2. During the honing operation, thoroughly check the cylinder bore.

• Repeatedly check the cylinder bore fit with the selected piston.

• All measurements of the piston or cylinder bore should be made with the components at normal room temperature.

3. When honing to eliminate taper in the cylinder bore, use full strokes the complete length of the cylinder bore.

4. Repeatedly check the measurement at the top, the middle and the bottom of the cylinder bore.

• The finish marks should be clean but not sharp.

• The finish marks should be free from imbedded particles or torn or folded material.

5. By measuring the selected piston at the sizing point and then by adding the average of the clearance specification, the final cylinder bore honing dimension required can be determined.

7EN266

11. Check the Cylinder head mounting surface for flatness, using a precision straight edge and feeler gauge.

• Set the straight edge on the sealing surface to be inspected.

• Put the feeler gauge at various locations; check the gap between the straight edge and the sealing surface.

• If the gap is greater than 0.05 mm (0.002 in.) within 152 mm (6 in.) at any sealing location, the block must be replaced.

• If the gap is found to be less than 0.05 mm (0.002 in.) at any sealing location and a cause for leakage is suspected, then the minor irregularities may be carefully machined from the block.

12. Check the Oil pan, timing cover and intake manifold mounting surfaces for nicks. Minor irregularities may be cleaned up with a flat file.

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6. When finished, the reconditioned cylinder bores should have less than or meet the specified outof-round and taper requirements.

7. After the final honing and before the piston is checked for fit, clean the cylinder bore with hot water and detergent.

• Scrub the cylinder bores with a stiff bristle brush.

• Rinse the cylinder bores thoroughly with clean hot water.

• Dry the cylinder bores with a clean rag.

• Do not allow any abrasive material to remain in the cylinder bores.

■ Abrasive material may cause premature wear of the new piston rings and the cylinder bores.

■ Abrasive material will contaminate the engine oil and may cause premature wear of the bearings.

8. Perform final measurements of the piston and the cylinder bore.

9. Permanently mark the top of the piston for the specified cylinder to which it has been fitted.

10. Apply clean engine oil to each cylinder bore in order to prevent rusting.

3. From the piston O.D. measurement, calculate the valve of the cylinder bore to which every cylinder is to be rebored.

Rebore diameter = Piston O.D. + 0.02 mm (8 x 10-4 in.) to 0.04 mm (1.6 x 10-3 in.)

(Cylinder-to-piston clearance) - 0.02 mm (8 x 10-4 in.) (honing allowance) 4. Rebore all cylinders to the calculated diameter.

NOTE Reboring should be made in the order of the cylinders numbers to prevent warping due to excessive temperature.

5. With a hone, a. Recondition the cylinders that have less than 0.025 mm (0.0010 in.) wear or taper. b. Bore and hone the cylinders that have more than 0.025 mm (0.0010 in.) of wear or taper to the smallest oversize piston that will permit complete resurfacing of all the cylinders.

6. Hone the cylinders to the finished size (piston O.D. + piston-to-cylinder clearance).

• During the honing operations occasionally: – Clean the cylinder bore.

– Measure the cylinder bore for a proper piston fit.

Reboring the Cylinders

NOTE

Boring Procedure

Important: Handle the pistons with care. Do not force the pistons through the cylinders until you hone the cylinder to the correct size. The piston can be distorted through careless handling.

! CAUTION Safety Glasses must be worn or eye injury may occur.

1. Before starting the honing or reboring operation, measure all the new pistons with the micrometer contacting at points exactly 90 degrees from the piston pin centerline.

1. To determine the size of the oversize piston to be used in all cylinders, choose the cylinder that requires the largest amount of reboring and use its size as the basis for all piston sizes.

2. Two kinds of oversize pistons are available; 0.50 mm (0.02 in.) O.S. and 1.00 mm (0.039 in.)

O.S. Those oversizes are based on the piston skirt O.D. measured along the datum line as shown in the figure. For all cylinders, select oversize pistons with the same diameter.

188016

7EN268

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2. File the top of the cylinder block in order to remove any dirt or burrs before using any type of boring bar.

3. Follow the instructions furnished by the manufacturer regarding the use of the boring equipment.

4. When reboring the cylinders, make sure all the crankshaft bearing caps are installed in the original position and direction.

5. Tighten the crankshaft bearing caps to the proper torque specifications in order to avoid distortion of the cylinder bores in the final assembly.

6. When making the final cut with the boring bar, leave 0.03 mm (0.001 in) on the cylinder bore diameter for finish honing. This gives the required position to the cylinder clearance specifications.

(Carefully perform the honing and boring operation in order to maintain the specified clearances between the pistons, the piston rings and the cylinder bores).

7. Check each cylinder for proper cylinder-to-piston clearance.

2. Apply sealant MCF P/N 2I4256 GM P/N 12346004 or equivalent to the outside diameter of the new front engine oil gallery plugs.

3. Install the new front engine block oil gallery plugs. A properly installed front engine oil gallery plug must be installed slightly below flush with the front face of the engine block.

5270

4. Apply threadlock GM P/N 12345382 or equivalent to the outside diameter of the NEW engine block core hole plugs.

5. Install the NEW engine block core hole plugs.

Properly installed engine block core hole plug must be installed flush with the bottom of the chamfer (1) of the engine block core hole.

Engine Block Plug Installation Installation Procedure Tools Required • J 41712 Oil Pressure Switch Socket

! CAUTION Wear safety glasses in order to avoid eye damage.

1. Install a new oil filter bypass valve. a. Install the oil filter bypass valve into the oil gallery bore until slightly below flush with the surface of the engine block. b. Using a pointed punch, stake the engine block area around the oil filter bypass valve. Stake in 3 locations 120 degrees apart.

6. Install the spring type S pin (crankshaft rear oil seal housing locator) (if required).

188023

-113-

11. Apply sealant MCF P/N 2I4256 GM P/N 12346004 or equivalent to the threads of the engine block right rear oil gallery plug, the engine block left rear oil gallery plug, and the engine block left side oil gallery plug.

Tightening torque for left and right side rear oil gallery plugs Tightening torque for left rear oil gallery plug

2.08 Kgf•m (15 lb•ft) [20N•m]

3.05 Kgf•m (22 lb•ft) [30 N•m]

334546

7. Apply sealant MCF P/N 2I4256/GM P/N 12346004 or equivalent to the outside diameter of the new expansion cup plug (balance rear bearing hole).

8. Install the new expansion cup plug (balance shaft rear bearing hole).

182841

12. Install the dowel straight pins (transmission locator) (if required).

334540

9.

Apply sealant MCF P/N 2I4256/GM P/N 12346004 or equivalent to the outside diameter of the new expansion cup plug (camshaft rear bearing hole).

10. Install the new expansion cup plug (camshaft rear bearing hole).

334548

-114-

13. Install the left side dowel pins (cylinder head locator) (if required).

16. Install the engine block coolant drain hole plug.

Tightening torque for engine block coolant drain hole plug

2.08 Kgf•m (15 lb•ft) [20N•m]

188052 334303

17. Apply sealant MCF P/N 2I4256/GM P/N 12346004 or equivalent to the threads of the engine oil pressure sensor fitting.

14. Install the right side dowel pins (cylinder head locator) (if required).

NOTE Important: Do not loosen the engine oil pressure fitting after the initial torque has been obtained.

Tightening torque for engine oil pressure sensor fitting

334314

15. Apply sealant MCF P/N 2I4256/GM P/N 12346004 or equivalent to the threads of the engine block coolant drain hole plug.

-115-

1.52 Kgf•m (11 lb•ft) [15 N•m]

18. Install the engine oil pressure sensor fitting.

23. Install the knock sensor.

NOTE

Tightening torque for 2.08 Kgf•m (15 lbf•ft) [20 N•m] knock sensor

Important: Do not rotate the engine oil pressure fitting clockwise more than 359 degrees after the initial torque has been obtained.

19. Rotate the engine oil pressure sensor fitting clockwise to the proper position (1) 50 degrees from the centerline.

10793

20. Apply sealant MCF P/N 2I4256/GM P/N 12346004 or equivalent to the threads of the engine oil pressure gauge sensor.

21. Install the engine oil pressure gauge sensor using the oil pressure switch socket J 41712.

22. Apply sealant MCF P/N 2I4256/GM P/N 12346004 or equivalent to the threads of the knock sensor.

Tightening torque for engine oil pressure gauge sensor

3.05 Kgf•m (22 lb•ft) [30 N•m]

J 41712

188018

-116-

Piston and Connecting Rod Removal and Installation

Removal steps 1.

2.

3.

4.

5.

6.

7.

8.

9.

Nut Rod Cap Bearing Bearing Piston and Connecting Rod Assy Pin Rod - Connecting Piston Ring Kit

-117-

Piston, Connecting Rod, and Bearing Removal

NOTE Important: Place matchmarks or numbers on the connecting rods and the connecting rod caps.

Assemble the connecting rod caps to the matching connecting rods.

2. Remove the connecting rod nuts.

3. Remove the connecting rod cap.

4. Remove the connecting rod bearings.

• Keep the bearings with the original connecting rod and connecting rod cap.

• Wipe the oil from the bearings.

• Wipe the oil from the crankpins.

Tools Required • J 24270 Cylinder Bore Ridge Reamer • J 5239 Guide Set 1. Use the cylinder boer ridge reamer J 24270 to remove the cylinder ring ridge. a. Turn the crankshaft until the piston is at the bottom of the stroke. b. Place a cloth on top of the piston. c. Use a ridge reamer to remove cylinder ring ridge. d. Turn the crankshaft so the piston is at the top of the stroke. e. Remove the cloth. f. Remove the cutting debris.

480549

11497

5. Use the guide set J 5239 to protect the crankshaft vournals and to remove the connecting rod and the piston out of the top of the engine block.

31373

-118-

Piston and Connecting Rod Disassemble

4. Mark, separate and organize the parts for assembly.

Tools Required • J 24086 Piston Pin Remover/Installer

NOTE Important: Mark the piston for installation to the proper cylinder.

1. Remove the piston rings from the pistons.

34671

Piston, Connecting Rod and Bearings Clean and Inspect Important: Measurement of all components should be taken with the components at room temperature.

Do not use a wire brush in order to clean any part of the piston.

! CAUTION

4967

2. Press the piston pin from the connecting rod using the piston pin remover/installer J 24086-C. 3. The piston pin has an interference fit into the connecting rod, and is full floating in the piston.

Safety Glasses must be worn or eye injury may occur.

1. Clean the piston and connecting rod in solvent.

2. Dry the components with compressed air.

J 24086-C

4965

34671

-119-

3. Clean the piston ring grooves with a suitable ring groove cleaning tool.

6. Inspect the piston pin for scoring, wear or other damage.

7. Measure the piston ring-to-piston ring groove side clearance. a. Insert the edge of the piston ring into the piston ring groove. b. Roll the piston ring completely around the piston.

■ If binding is caused by a distorted piston ring groove, MINOR imperfections may be removed with a fine file.

■ If binding is caused by a distorted piston ring, replace the piston ring.

4977

4. Clean the piston oil lubrication holes and slots.

5. Inspect the piston for the following: • Eroded areas (1) on the top of the piston • Scuffed or damaged skirt (2) • Damage to the pin bore (3) • Cracks in the piston ring lands, the piston skirt or the pin bosses • Piston ring grooves for nicks, burrs or other warpage which may cause the piston ring to bind

4969

8. Measure the piston ring side clearance with a feeler gauge.

9. If the side clearance is too small, try another piston ring set.

10. If the proper piston ring-to-piston ring groove clearance cannot be achieved, replace the piston and pin assembly.

11. To determine the proper piston ring side clearance, refer to General Specifications.

156168

22934

-120-

12. To determine piston pin-to-bore clearance, use a micrometer and measure the piston pin.

188016

16. Inspect the connecting rod for an out-of-round bearing bore. Refer to General Specifications.

4976

13. To determine piston pin-to-bore clearance, use an inside micrometer and measure the piston pin bore.

14. To determine the piston pin-to-bore clearance, subtract the piston pin diameter from the piston pin bore diameter. Refer to General Specifications.

156167

17. Inspect the connecting rod for twisting.

18. Inspect the connecting rod for damage to the bearing cap and bolt threads.

4975

15. Measure the piston with a micrometer at a right angle to the piston pin bore, measure the piston at 11 mm (0.433 in) from the bottom of the skirt. Refer to General Specifications. If the piston is not within specifications, replace the piston and pin as an assembly.

156169

-121-

19. Measure the piston compression ring end gap.

Important: Fit each compression ring to the cylinder in which it will be used.

20. Place the compression ring into the cylinder bore. a. Push the compression ring into the cylinder bore to approximately 6.5 mm (0.25 in) above the ring travel. The ring must be square to the cylinder wall. b. Use a feeler gauge in order to measure the end gap. c. Select another size ring set if the end gap exceeds specifications. Refer to General Specifications.

2. Measure the cylinder bore guage J 8087 with a micrometer and record the reading.

J 8087

4974

3. With a micrometer or caliper at a right angle to the piston pin bore, measure the piston 11 mm (0.433 in) from the bottom of the skirt.

4. Subtract the piston diameter from the cylinder bore diameter in order to determine piston-tobore clearance. Refer to General Specifications.

5. If the proper clearance cannot be obtained, then select another piston and measure the clearances.

If the proper fit cannot be obtained, the cylinder bore may require honing or boring.

6. When the piston-to-cylinder bore clearance is within specifications, permanently mark the top of the piston for installation into the proper cylinder.

Piston Selection Tools Required • J 8087 Cylinder Bore Gauge Important: Measurements of all components should be taken with the components at normal room temperature.

For proper piston fit, the engine block cylinder bores should not have excessive wear or taper.

A used piston and piston pin set may be reinstalled if, after cleaning and inspection, the piston and piston pin are within specifications.

1. Use the cylinder bore guage J 8087 to measure the cylinder bore diameter. Measure at a point 64 mm (2.5 in) from the top of the cylinder bore and 90 degrees to the crankshaft centerline.

J 8087

188016

4972

-122-

Piston, Connecting Rod and Bearing Installation

Important: The mark on top of the piston must face the front of the engine block. When assembled, the flanges on the connecting rod and connecting rod cap should face the front of the engine block on the left bank, and to the rear of the engine block on the right bank.

4. Install the piston and connecting rod assembly, and the piston ring compressor J 8037 into the proper cylinder bore.

Tools Required •J 5239 Guide Set •J 8037 Piston Ring Compressor •J 36660 Torque Angle Meter 1. Coat the following components with clean engine oil: • The piston • The piston rings • The cylinder bore • The bearing surfaces 2. Install the guide set J 5239 onto the connecting rod bolts.

J 5239

J 8037 492144

5. Use the piston ring compressor J 8037 and the guide set J 5239 to lightly tap the top of the piston with a wooden hammer handle. a. Hold the piston ring compressor J 8037 firmly against the engine block until all of the piston rings enter

387765

3. Install the piston ring compressor J 8037 onto the piston and compress the piston rings.

J 8037

J 8037

480573

5159

-123-

b. Use the guide set J 5239 to guide the connecting rod onto the crankshaft journal.

6. Remove the piston ring compressor J 5239.

8. After the piston and connecting rod assemblies have been installed, then lightly tap each connecting rod assembly (parallel to the crankpin) in order to insure that the connecting rods have side clearance.

J 5239

5163

9. Use a feeler gauge or a dial indicator to measure the connecting rod side clearance between the connecting rod caps. The connecting rod side clearance should be 0.16-0.44 mm (0.006-0.017 in.).

31373

7. Install the connecting rod cap, bearings and nuts.

Tightening torque 1st pass for rod cap nuts 2.77 Kgf•m (20 lbf•ft) [27 N•m]

Piston and Connecting Rod Assemble Tools Required • J 24086-C Piston Pin Remover/ Installer

• On the final pass, use the electronic torque angle meter J 36660 to tighten the nuts an additional 70 degrees.

Tightening torque for rod cap nuts

! CAUTION Avoid contact with HOT components. Wear safety glasses and protective gloves to avoid personnel injury.

Final pass Additional 70°

NOTE Important: Applying excessive heat to the connecting rod may damage or distort the rod. Rod temperature SHOULD NOT exceed 315°C (600°F). At this temperature, the end of the connecting rod will turn a straw color upon visual inspection.

NOTE Important: After the MCF-1083 (J 24086-C) installer hub bottoms on the support assembly, DO NOT exceed 35,000 kPa (5,000 psi) or the tool may be damaged.

480545

-124-

2. Install the piston rings onto the piston. a. Install the oil control piston ring spacer. b. Install the lower oil control piston ring. c. Install the upper oil control piston ring. d. Install the lower compression piston ring. The mark on the side of the piston ring should face the top of the piston. e. Install the upper compression piston ring. The mark on the side of the piston ring should face the top of the piston.

NOTE Important: When assembling the piston and connecting rod, the mark on the top of the piston must point to the front of the engine block. The left bank connecting rods should have the flange face toward the front of the engine block. The right bank connecting rods should have the flange face toward the rear of the engine block.

The piston pin has an interference fit into the connecting rod and is full floating in the piston.

1. Install the piston pin and connecting rod assembly. a. Lubricate the piston holes in both the piston and the connecting rod assembly with clean engine oil. b. Use a torch and apply MILD heat to the piston pin end of the connecting rod. c. Press the piston pin into the piston and connecting rod assembly using the piston pin remover/installer J 24086-C. d. Inspect for proper installation of the piston and piston pin. The piston must move freely on the piston pin with no binding or interference.

490763

J 24086-C

3. Space the compression piston ring end gaps 120 degrees apart.

4. Space the oil control piston ring end gaps a minimum of 90 degrees apart.

4965

NOTE Important: Use a piston ring expander to install the piston rings. The rings may be damaged if expanded more than necessary.

-125-

-126-

Gasoline Carburetor Removal and Installation

1.

2.

3.

4.

5.

6.

7.

8.

Carburetor Fuel Inlet Intake Air Connector Accelerator Cable Carburetor Connector Gasket Adapter Gasket

-127-

Carburetor Assembly Removal Procedure 1. Remove Intake Air Connector.

2. Disconnect Accelerator Cable from Carburetor.

3. Disconnect Carburetor Connector.

NOTE Important: Mark and organize all hoses for assembly.

4. Disconnect the Following Hoses: • Fuel inlet hose • Emmision control hoses • Vacuum Lines 5. Remove the four carburetor mounting nuts.

6. Lift out the carburetor.

7. Cover the inlet hole of the intake manifold with a cloth.

PO5026

PO5024

PO5034

-128-

Carburetor Assembly (Upper) Removal and Installation 7 1 15 2 27

28 29 34 6 4 36

33 32 30

35

31 5

38 37

40

39

16

26 24

22

Disassembly steps Stud bolt Nipple union Pivot bolt Acceleration pump arm FICB link Air Horn Wire clamp Pivot pin Wire Float Plunger Spring Needle valve Acceleration pump plunger Plunger boot Air horn gasket Needle valve seat Gasket Screw Retainer

18

23

25 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

16.

17.

18.

19.

20.

3

21.

22.

23.

24.

25.

26.

27.

28.

29.

30.

31.

32.

33.

34.

35.

36.

37.

38.

39.

40.

Power piston Spring Primary upper slow jet Screw Coil housing Gasket Screw Cover Spring E-ring Stopper Spring Collar Diaphragm Solenoid Valve Gasket Screw Choke lever Screw Thermostat housing

-129-

21 20

17 14

19 13

10

12 11 9 8

-130-

Carburetor Assembly (Lower) Removal and Installation

1 19

13

4

7 6

5

18 14 3

2

5

20

15 17

16 12

Disassembly steps 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

16.

17.

18.

19.

20.

21.

22.

23.

24.

25.

26.

27.

28.

29.

30.

Discharge weight Spring Check ball Plunger spring Retainer Check ball Primary slow jet Plug Spring Ball Plug Ball 23 Power valve Passage plugs Gaskets Primary main jet Gasket Passage ring Screw Primary small venturi Gasket Snap ring Screw Fast idle cam breaker (FICB) Fast idle cam Passage screw Bolt Carburetor Body Carburetor flange Insulator

8

11

21

24

28

27

25 30 22

29 26

-131-

9 10

Carburetor Disassembly

3. Disconnect Fast Idle Cam Breaker (FICB) Link.

Hint: The following instructions are organized to allow work on only one component group at a time.

This will help avoid confusion between similar looking parts from different subassemblies that are on the workbench at the same time.

1. To facilitate reassembly, arrange parts in order.

2. Be careful not to mix up or lose balls, clips or springs.

Air Horn Disassembly

PO5033

1. Remove Carburetor Stud Bolt and Nipple Union.

4. Remove Air Horn Assembly. a. Remove the seven screws and following parts: • Number plate (1) • Wire clamps (2) • Switch harness clamp (3) • Coil housing and solenoid valve harness clamp (4) b. Lift off the air horn assembly together with the air horn gasket.

PO4859

2. Remove Acceleration Pump Arm. a. Remove the snap ring from the pump connecting link. b. Remove the pivot bolt. c. Disconnect the pump arm from the pump plunger. d. Disconnect the pump connecting link from the throttle lever and remove the pump arm and pump connecting link.

PO5522

5. Remove Float and Needle Valve. Remove the float pivot pin, float and needle valve subassembly.

PO5109 PO5035

-132-

6. Remove Acceleration Pump Plunger. a. Remove the pump plunger and boot. b. Remove air horn gasket.

9. Remove Primary Upper Slow Jet.

PO5082

10. Disconnect Wires from Carburetor Connector. a. Pry up the locking lugs with a screwdriver and pull out the terminal.

11. Remove Coil Housing. a. Remove the three screws, retainer, coil housing and gasket.

PO4976

7. Remove Needle Valve Seat. a. Remove the needle valve seat and gasket.

PO5083

8. Remove Power Piston. a. Remove the screw, retainer, power piston and spring.

PO4723

12. Remove Choke Breaker (CB). a. Remove the three screws, cover and spring.

PO4721

PO4722

-133-

b. Remove the E-ring, stopper, spring collar and diaphragm.

b. Remove the two screws and thermostat housing.

PO4853

PO4725

15. Remove Fast Idle Cam Breaker (FICB) Link. a. Remove the screw and FICB link.

13. Remove Fuel Cut Off Solenoid Valve. a. Remove the solenoid valve and gasket.

PO4977

PO4724

14. Remove Thermostat Housing. a. Remove the screw and choke lever.

Carburetor Body Disassembly 1. Remove Check Balls for Acceleration Pump. a. Remove the pump discharge weight, spring and large ball. b. Remove the plunger spring.

PO4727

PO4719

-134-

c. Using tweezers, remove the ball retainer. d. Remove the small ball.

4. Remove Power Valve.

PO4890 PO5036

5. Remove Primary Main Jets. a. Remove the two passage plugs and gaskets.

2. Remove Slow Jets. a. Remove the primary slow jet.

PO4718 PO4926

b. Remove the primary main jets and gaskets.

3. Remove Check Balls for Auxiliary Acceleration Pump (AAP). a. Remove the plug, spring and ball (a). b. Remove the plug and ball (b).

PO4949

PO4944

-135-

6. Remove Small Venturies. a. Remove the passage ring.

8. Remove Fast Idle Cam.

PO4714

9. Separate Carburetor Body and Flange. a. Remove the passage screw and spring washer.

PO4858

b. Remove the two screws, primary small venturi and gasket.

PO5019

PO5509

7. Remove Fast Idle Cam Breaker (FICB). a. Remove the snap ring. b. Remove the two screws. c. Disconnect the link, and remove the FICB.

b. Remove the two bolts. c. Separate the body and flange. d. Remove the insulator.

PO4733

PO4712

-136-

General Cleaning Procedure

2. Inspect Power Piston. a. Check that the power piston moves smoothly.

1. Clean Disassembled Parts Before Inspection. a. With a soft brush, wash and clean the cast parts in carburetor cleaner. b. Clean the carbon around the throttle valve. c. Thoroughly wash the other parts in carburetor cleaner. d. Blow all dirt and other foreign material from the jets, fuel passages and restrictions in the body.

PO4893

3. Inspect Power Valve. a. Check for faulty opening and closing action.

PO4975

Carburetor Inspection 1. Inspect Float and Needle Valve. a. Inspect the pivot pin (1) for scratches and excessive wear. b. Inspect the float (2) for broken lips and wear in the pivot pin holes. c. Inspect the spring (3) for breaks and deformation. d. Inspect the needle valve (4) and plunger (5) for wear or damage. e. Inspect the strainer (6) for rust and breaks.

PO4740

4. Inspect Fuel Cut Off Solenoid Valve. a. Connect the connector terminals to the battery terminals. b. You should feel a “click” from the solenoid valve when the battery power is connected and disconnected. If the solenoid valve is not operating properly, replace it.

PO4739

PO4741

-137-

5. Inspect Choke Heater (Coil Housing). a. Using an ohmmeter, measure the resistance between the terminals.

2. Install Fast Idle Cam.

Resistance (Cold): 17.3 - 18.7 Ω at 20°C (68°F) If a problem is found, replace the choke heater.

PO4714

3. Install Fast Idle Cam Breaker (FICB). a. Connect the link, and install the FICB with the two screws. b. Secure the link with the snap ring.

PO4742

Carburetor Assembly Hint: Use new gaskets and O-rings throughout.

1. Assemble Carburetor Body and Flange. a. Assemble the flange and body together with a new insulator. b. Install the two bolts.

PO4733

4. Install Small Venturies. a. Install a new gasket and the primary venturi with the two screws.

PO4712

c. Install the passage screw together with the spring washer.

PO4946

PO5509

-138-

b. Install the passage ring.

6. Install Power Valve.

PO4890

PO4858

7. Install Primary Slow Jet.

5. Install Primary Main Jets. a. Install the primary main jets with new

PO4873 PO4871

8. Install Check Balls for Acceleration. a. Install the plunger small ball. b. Using tweezers, install the ball retainer.

b. Install the primary passage plugs with new gaskets.

PO4718

PO5036

-139-

c. Install the plunger spring (c). d. Install the pump discharge large ball, spring and weight (d).

b. Install the choke lever with the screw.

PO4727

3. Install Fuel Cut Off Solenoid Valve. a. Install a new O-ring to the solenoid valve. b. Install the solenoid valve together with a new gasket.

PO4891

Air Horn Assembly 1. Install Fast Idle Cam Breaker (FICB) Link.

Install the FICB link with the screw.

PO4724

4. Install Choke Breaker (CB). a. Install the diaphragm into the thermostat case, and install the collar, spring and stopper with the E-ring. b. Insert the shaft of the diaphragm into the hole of the thermostat case.

PO4977

2. Install Thermostat Housing. a. Install the thermostat housing with the two screws.

PO4853

PO4725

-140-

c. Install the following parts with the three screws: • Spring

b. Pull on the wire to check that it is securely locked.

PO4738

7. Install Primary Upper Slow Jet. PO5425

5. Install Coil Housing. a. Install the gasket to the thermostat case. b. Align the bi-metal spring with the wire spring and install the coil housing, aligning the choke lever as shown in the illustration.

PO5082

8. Install Power Piston. a. Install the spring and power piston with the retainer and screw.

PO5060

c. Align the scale center line of the thermostat case with the coil housing line, and install the plate with the three screws. d. Check the choke valve action.

6. Connect Wires to Connector. a. Push in the terminal until it is securely locked in the connecting lug.

PO4919

PO4730

-141-

9. Install Needle Valve Seat. a. Install the valve seat together with a new gasket.

c. Allow the float to hang down by its own weight.

Measure the clearance between the float tip and air horn. Float level (Raised position): 7.0 mm (0.276 in.). Hint: This measurement should be made without a gasket on the air horn.

PO5083

10. Adjust Float Level. a. Insert the needle valve, spring and plunger into the needle valve seat.

Hint: After adjusting the float level, install the clip onto the needle valve.

PO4889

d. Adjust by bending the portion of the float lip marked A.

PO4857 PO4735

b. Install the float with the pivot pin.

e. Lift up the float. Measure the clearance between the needle valve plunger and float tip. Float level (lowered position): 0.9 - 1.1 mm (0.035 - 0.043 in.)

PO4860

PO4736

-142-

f. Adjust by bending the position of the float lip marked B. g. After adjusting the float level, remove the float, plunger, spring and needle valve.

13. Install Needle Valve and Float. a. Hook the needle valve clip to the lip portion of the float.

PO4973

PO4737

b. Install the float and secure it with the pivot

h. Assemble the clip onto the needle valve.

PO4720 PO5035

11. Install New Air Horn Gasket. a. Place the air horn gasket on the air horn.

12. Install Acceleration Pump Plunger. a. Install a new boot and the pump plunger.

14. Install Air Horn Assembly. a. Install the wire clamp in position.

PO5037

PO4976

-143-

b. Place the air horn in the carburetor body. c. Install the following parts with the seven screws: • Number plate (1) • Wire clamps (2) • Switch harness clamp (3) • Coil housing and solenoid valve harness clamp (4)

17. Install Nipple Union. a. Install a new gasket and nipple union.

18. Check for Smooth Operation of Each Part.

PO4974

Carburetor Adjustment 1. Check and Adjust Throttle Valve Opening. a. Check the full opening angle of the primary throttle valve.

Standard angle: 90° from horizontal

PO5522

15. Connect Fast Idle Cam Breaker (FICB) Link.

PO5033 PO5032

16. Install Acceleration Pump Arm. a. Connect the pump connecting link to the throttle lever. b. Connect the pump arm to the pump plunger. c. Install the pump arm with the pivot bolt. d. Secure the link with the snap ring.

b. Adjust by bending the primary throttle stop lever.

PO5113 PO5109

-144-

2. Set Automatic Choke. a. Set the coil housing line so that it is aligned with the center line of the thermostat housing.

Hint: The choke valve becomes fully closed when the atmospheric temperature reaches 30°C (86°F).

b. Check the primary throttle valve angle.

Standard angle: 23.3° - 25.3° from horizontal

PO5074

c. Adjust by turning the fast idle adjusting screw.

PO5039

b. Depending on truck operating conditions, turn the coil housing and adjust the engine starting mixture.

If too rich ........ Turn clockwise.

If too lean ....... Turn counterclockwise.

PO5077

4. Check and Adjust Unloader. a. With the primary throttle valve fully opened, check the choke valve angle.

Standard angle: 35° - 39° from horizontal

PO5088

3. Check and Adjust Fast Idle Setting. a. Position the fast idle lever onto the 1st step as shown.

PO5068

PO4909

-145-

b. Adjust by bending the unloader lever.

b. Apply vacuum to the FICB and release it. c. Check that the choke linkage moves, and that the fast idle cam is released to the 3rd step.

PO5078

5. Check and Adjust Fast Idle Cam Breaker (FICB). a. Set the fast idle cam: • While holding the throttle slightly open, push the choke valve closed, and hold it closed as you release the throttle valve.

PO5511

d. Adjust by bending the FICB lever.

PO5090

6. Check and Adjust Choke Breaker (CB). a. Set the fast idle cam. b. Apply vacuum to the CB. c. Check the choke valve angle.

Standard angle: 43.5° - 44.5° from horizontal

PO5028

• Check that the fast idle lever is set in the 1st step of the fast idle cam as shown.

PO4913

PO5067

-146-

d. Adjust by turning the CB adjusting screw.

c. Adjust turning the idle speed adjusting screw.

PO5485

PO5087

7. Check and Adjust Acceleration Pump. a. Apply vacuum to fast idle cam breaker (FICB). b. Rotate the throttle shaft and check the length of the stroke.

Standard stroke: 10.9 mm (0.429 in.). c. Adjust the pump stroke by bending the connecting link.

9. Preset Idle Mixture Adjusting Screw. If the idle mixture adjusting screw has been removed, fully screw it in and then unscrew it the following amount: Standard: Return 2 3/4 turns from fully closed position.

NOTE Use care not to screw it in too tightly and damage the screw tip.

PO5021

8. Preset Idle Speed Adjusting Screw. a. Apply vacuum to fast idle cam breaker (FICB). b. Check the primary throttle valve angle.

Standard angle: 16° from horizontal

PO5086

10. Check for smooth operation of each part.

11. Install carburetor stud bolt.

Operational Adjustments 1.

2.

3.

4.

5.

Start engine.

Allow engine to reach operating temperature.

Install tachometer.

Idle speed adjustment.

Idle mixture adjustment.

Adjust by using the following tools: 1. Tachometer 2. Exhaust Gas Analyzer 3. Vacuum Gauge PO5075

-147-

Carburetor Installation

3. Connect Carburetor Connector.

4. Connect and Adjust Accelerator Cable. a. Loosen the locknut of the Adjusting Nut at carburetor and rotate the Adjusting Nut until all slack from the accelerator cable is removed. Do not set cable so tight as to pull the accelerator pedal. b. Adjustment of the accelerator pedal is required to obtain correct low idle setting. This requires the installation of the floor plate and the engine cover open in order to view the movement of the mechanical throttle body bell crank. c. Adjust the throttle cable tension at the throttle position sensor to 0-2 mm of free play at accelerator pedal before the throttle position sensor starts to move. The clevis at both ends of the cable should not be slack. d. Loosen the locking nut on the accelerator pedal stop bolt to allow adjustment of the accelerator pedal stop bolt. e. Depress the accelerator pedal while viewing the throttle body bell crank. The bell crank will rotate as the accelerator pedal is depressed. f. Set the stop bolt height so the bell crank moves the full range of motion within 0-1 mm from stop plate at carburetor. Tighten the locknut to secure the accelerator stop bolt once adjustment is obtained. g. Start the engine but do not make adjustment until the engine is at operating temperature and the vacuum switch has opened to pull the choke to the off position. h. Slowly depress and release the Accelerator Pedal a few times. Check that there is no slack in the cable when the stepping motor lever is not in motion. The cable will be loose while choke is ON and the cable will be tight when the choke is OFF. Readjust as necessary. i. Install Intake Air Connector. j. Adjust Idle Speed (750 + - 50) and Idle Mixture. k. High RPM cannot be adjusted. It is controlled by the ECU. l. Adjust Choke. m. Check torque converter stall speed per chassis service manual.

1. Install Carburetor. a. Place the insulator and new gaskets on the intake manifold.

PO5025

b. Place the carburetor on the insulator. c. Install the four carburetor mounting nuts.

Tightening torque for carburetor mounting nuts

130 Kgf•m (9 lb•ft) [13 N•m]

PO5034

2. Connect the Following Hoses. a. Emission control hoses. b. Fuel inlet hose. c. Outer vent control hose. d. Vacuum lines.

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Electrical Throttle and Governor Control System System Operation Description This controller activates gasoline engine carburetor with a stepping motor to vary air-fuel ratio for controlling engine rpm. Engine rpm is controlled by varying the position of the accelerator pedal. It has a built-in fault detection circuit to provide a fail-safe processing function.

Characteristics Low idle: 750 ± 50 rpm High idle: 2650 rpm Speed regulation (rated load): +/- 50% (at 2650 rpm) Instantaneous maximum speed: 2800 rpm Governor: All-speed type Fail-safe processing function This controller detects any of the following faults to perform necessary fail-safe processing and causes the check lamp to indicate error codes in a flickering manner, thereby alerting the operator of a malfunction.

A fault code is stored in the memory even after the power has been turned OFF and, when the diagnostic switch is turned ON, it is displayed.

1.

2.

3.

4.

5.

6.

7.

8.

Engine Over Speed Accelerator sensor fault Idle switch fault Throttle CLOSE position detection switch fault Throttle OPEN position detection switch fault Stepping motor fault Rotary pulse fault Alternator fault

The motor output shall perform PWM of approximately 60% to prevent the motor from overheating.

-149-

ECU Input/Output Interfaces The following table shows the input/output specifications of this controller.

Connector No. Signal

Connection

Input/Output

Specification

A1

AP

Motor A phase (blown)

Output

Motor output

A2

BP

Motor B phase (red)

Output

Motor output

A3

OUT1

Check lamp

Output

Open collector output

A4

OUT2

Output

Open collector output

A5

IN1

Throttle CLOSE position detection switch

Input

Contactor input (connected to GND)

A6

AI1

Accelerator sensor signal

Input

Analog input

A7

AI2

Alternator voltage signal

Input

Analog input

A8

P12V

Controller power source

B1

AN

Motor ~ A phase (amber)

Output

Motor output

B2

BN

Motor ~ B phase (yellow)

Output

Motor output

B3

RYNO

Relay output

Output

Non-voltage contactor output

B4

OUT3

Output

Open collector output

B5

IN2

Throttle OPEN position detection switch

Input

Contactor input (connected to GND)

B6

IN3

Idle switch

Input

Contactor input (connected to GND)

B7

GND

Accelerator sensor ground

0V

B8

VCC

Accelerator sensor power source

5V

C1

P12V

Motor common (white)

C2

GND

Throttle position detection switch (R)

C3

RYC

Relay output (R)

C4

REF HI

C5

GND

C6

Power from battery (12V)

Output

12V 0V

Output

Non-voltage contactor output

Pulse input

Input

Pulse input interface

Pulse input (R)

Input

Pulse input interface

IN4

Diagnostic switch

Input

Contactor input (connect to GND)

C7

IN5

Test program switch

Input

Contactor input (connect to GND)

C8

GND

Controller GND

0V

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ECU Schematic

-151-

Method of Operation

Speed Control

Initial Setting Turning the power ON allows the controller to activate the motor in the direction of decreasing the fuel. Under this condition, the throttle CLOSE position detection switch turns ON and, after the motor has been activated in the direction of increasing the fuel, the throttle OPEN position detection switch turns ON. By these actions, the starting point of the stepping motor is settled. Now, the controller is on standby at the starting position (opens 45 degrees from the throttle CLOSE position). Since the starter function is now inhibited, the starter inhibit relay within the controller is turned OFF. With the controller on standby, the motor can be activated by depressing the accelerator pedal.

Once the accelerator pedal is depressed, the throttle position corresponding to the stroke of the accelerator pedal is maintained until engine start-up is detected.

Low Idle Speed When the accelerator sensor is in low idle region, the controller allows the engine to run at 750 rpm.

The target of steady-state speed regulation is +/50 rpm.

High Idle Speed When the accelerator sensor is in full open position, the controller allows the engine to run at 2650 rpm.

The engine speed is so controlled that it does not exceed 2800 rpm even if the accelerator pedal is suddenly operated or if the engine is brought into no-load condition. The engine is considered to be overrunning if its speed exceeds 3000 rpm. In such a case, the current to the governor drive motor is cut off to bring the throttle to the full close position.

Normal Speed Region The engine runs at the controlled speed determined on the basis of the “accelerator position characteristic” curve. (This is all-speed characteristic.)

The controlled engine speed with a rated load is 2650 ± 50 rpm.

Stopping As the starter switch key is turned to OFF position, the controller power source is turned OFF at the same time, the ignition pulse dies away and the fuel cut-off solenoid is operated to shut down the engine.

If the power source is turned ON while the engine is in the process of being shut down, the initial setting outlined above is omitted. In such a case, the engine speed is reduced to low idle level, and the position of the throttle CLOSE position detection switch is detected. The control function is continued on the basis of this switch position.

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ECU Diagnostics Tester Procedure Tools required • ECU Diagnostics Tester (91868-02300) and your Lift Truck Service Manual.

• Inductive Tachometer • Digital Volt/Ohmmeter How to read error code flashes, when an error occurs 1. Turn the engine off.

2. Connect the Diagnostic Tester harness to the engine harness connector located near the distributor.

3. Move the toggle switch on the ECU diagnostic tester to OFF position.

4. Turn the truck key switch to the ON position (the light on the tester will flash continuously at 1 second intervals).

5. Flip the toggle switch on the tester to ON position - Error codes will flash at 3 second intervals. If there are no errors, the light will continue to flash at 1 second intervals.

6. From the error code, determine the reason and result for the error from the following table.

7. Turn the key switch OFF and remove the diagnostic tool.

How to clear the error history from the ECU Part numbers 16A94-01000, 16A94-11000, 16A94-31000 1. Repeat Steps 1 and 2 above.

2. Move the toggle switch on the tester to ON position.

3. Turn the truck key switch to ON position (the light on tester will flash continuously at 1 second intervals).

4. Turn the key switch OFF and remove the diagnostic tool.

How to clear the error history from ECU Part number 16A94-41000 1. Install diagnostic tool.

2. Turn the diagnostic tool switch to ON position.

3. Press the throttle pedal down 50% or more and while holding the throttle pedal down, turn the ignition switch to ON position. The fault codes are now cleared.

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GM 4.3L, G6 Gasoline Engine ECU Error Code Description (ECU Part Numbers 16A94-01000, 16A94-11000, 16A94-31000) Error Code

Condition

Cause

Effects on Operation

1

Engine Over Speed

Engine rpm at 3000 for more than 0.30 seconds

2

Input signal from accelerator sensor is out of specification

Input voltage signal from accelerator sensor Close throttle valve fully, shut power exceeded 97% of maximum input signal source of starter, back to normal voltage from accelerator sensor did not operation after restarting exceed 10% of maximum when idle position sensing switch on the accelerator sensor is off

3

Idle position sensing Idle position sensing switch on accelerator switch on accelerator sensor stayed at on when input voltage sensor is not correct signal from accelerator sensor exceeds 50% of maximum

4

Throttle close position sensing switch on carburetor is not correct

During calibration the ECU did not receive Close throttle valve fully, shut power on-signal from throttle close position sensing source to starter, back to normal switch even if stepping motor was moved operation after restarting correctly

5

Throttle open position sensing switch on carburetor is not correct

During calibration the ECU did not receive Can be operated normally except on-signal from throttle open position sensing limiting engine speed to 1500 rpm, back to normal operation after restarting switch even if stepping motor was moved correctly (98 degrees)

6

Stepping motor is not ECU received unexpected on-signal from correct throttle open or close position sensing on carburetor

7

Revolution pulse signal ECU did not receive revolution pulse signal Close throttle valve fully, back to from distributor is not from distributor for more than specified period normal operation after restarting correct while voltage of alternator L terminal was within normal operating range, before engine reaches operating speed: 1 second, after engine reaches operating speed: 0.1 seconds

8

Alternator problem

Can be operated normally except limiting engine speed to 1500 rpm, back to normal operation after restarting

Close throttle valve fully, back to normal operation after restarting

Voltage of alternator L terminal remained Close throttle valve fully, back to lower than normal operating range over 30 normal operation after restarting seconds when ECU receives revolution pulse signal from distributor

Engine Initialize To reset error history

Close throttle valve fully back to normal operation after restarting

Every 30 engine starts Turn key switch on with check box switch on

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GM 4.3L, G6 Gasoline Engine ECU Error Code Description (ECU Part Number 16A94-41000) Error Code

Condition

1

Engine Over Speed

2

Accelerator sensor is out of specification

3

4

Cause Engine at 3000 rpm for more than 0.30 seconds

Input voltage signal from accelerator sensor exceeded 4.61 volts for more than 1.0 sec., input signal voltage from accelerator sensor did not exceed 10% of maximum for more than 1.0 sec., when the idle position sensing switch is on the accelerator sensor Idle position sensing Idle position sensing switch on accelerator switch on accelerator sensor stayed at on for more than 1.0 sec., sensor is not correct while input voltage signal from accelerator sensor exceeded 50% of maximum Throttle close position During calibration the ECU did not receive sensing switch on on-signal from throttle close position sensing carburetor is not switch, even if stepping motor was moved correct correctly.

5

Throttle open position sensing switch on carburetor is not correct

6

Stepping motor is not ECU received unexpected on-signal from correct throttle open or close position sensing switches on carburetor for more than 1 sec.

Revolution pulse signal ECU did not receive revolution pulse signal from distributor is not from distributor for more than 0.2 seconds correct

7

Carburetor Stepping motor Initializes To reset error history

During calibration the ECU did not receive on-signal from throttle open position sensing switch even if stepping motor was moved correctly (98 degrees).

Effects on Operation Close throttle valve fully, back to normal operation when engine goes down to under 2000 rpms Close throttle valve fully, shut power source of starter, back to normal operation after restarting

Close throttle valve fully, back to normal operation after restarting

Close throttle valve by 5% of maximum stroke and shut power source of stepping motor, back to normal operation after restarting Operates normally except limiting engine stepping motor stroke to 90 degrees, back to normal operation after resetting error history Close throttle valve fully, back to normal operation after restarting

Close throttle valve fully, back to normal operation when ECU receives a revolution pulse signal for more than 0.2 sec.

After every 5 engine starts or after the error codes have been cleared from the ECU. (Carburetor will cycle from Full Open to Full Close to set throttle stroke) Install diagnostic tool 91868-02300. Turn the diagnostic tool switch to the ON position.

Press throttle pedal down 50% or more and while holding the throttle pedal down turn the ignition switch to the ON position. The fault codes are now cleared.

-155-

Ignition System and Distributor Removal and Installation

➧ A ➧ ➧A ➧ ➧ A ➧ ➧A ➧ ➧ ➧ ➧B➧ ➧C➧ ➧D➧

Removal steps 1. Spark Plug Wires 2. Ignition Coil Wire 3. Coil 4. Distributor 5. Gasket 6. Spark Plugs

-157-

Ignition System - Distributor Removal and Installation

1

13

6 7

2

14 15

8

16

9 3 10

Removal steps 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

16.

11

Screw Distributor Cap Rotor Shaft Assembly Retainer Shield Sensing Coil Pole, Stationary Screw (4) EST Module Pin Housing Tab Washer Washer Gear Roll Pin

4

12 5

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➧ ➧C Distributor Removal

Distributor Disassembly 1. Remove the rotor from the shaft by lifting straight from the end of the shaft.

2. Put an alignment mark on the shaft and gear for correct installation. Use a small punch to remove the roll pin as shown. Do not damage the shaft or gear.

NOTE Position the engine to TDC (top dead center) #1 compression stroke before removing the distributor.

This will be a good reference point when reinstalling the distributor in the engine.

! CAUTION Before starting removal steps of coil or distributor, disconnect the negative battery cable.

1. Remove all wires from the distributor, spark plug, coil and harness wires.

2. Remove the two screws on the distributor cap and remove the cap.

3. Place a mark on the distributor housing where the rotor is pointing. Put a corresponding mark on the distributor housing and on the engine.

This will be a known starting point for reassembly.

4. Remove the bolt and clamp that hold the distributor in the engine and remove the distributor.

ESTDISO1

3. Remove the gear, washer, and tab washer.

4. Remove the shaft with the pole piece and plate from the housing.

! CAUTION When the distributor is disassembled, the retainer must be replaced. NEVER use an old retainer.

5. Remove the retainer from the housing using a screwdriver. Remove the shield.

6. Remove the sensing coil connector from the module. Lift the locking tab with a screwdriver.

Remove the sensing coil.

7. Remove the two screws that fasten the EST module to the plate. Remove the EST module.

Distributor Assembly

NOTE A small amount of silicon grease is supplied with each replacement module. If more silicon grease is needed, use the 5P8937 Heat Sink Compound.

34403

5. Remove the distributor gasket and replace with a NEW one at reassembly.

1. Completely cover the bottom of the EST module with a thin layer of 5P8937 Heat Sink Compound or an equivalent compound for heat transfer.

-159-

➧B➧ Coil Installation and Testing

5. Install the coil wire on the distributor and the coil.

6. Make sure all wires fit tightly around the distributor cap and spark plugs. Install each wire in the supporting clips and make sure all wires are kept clear of the exhaust manifold and heat shields.

1. Ignition coil testing, open and short circuits, and coil can be tested on or off the engine.

2. Make sure all test points are clean from paint, dirt, grease and oil before testing. Disconnect all wires from the coil before testing.

COIL01

➧B

➧

IGNITSY2

3. Ignition coil testing. a) Connect a volt/ohmmeter as shown in step 1.

Set the meter on ohms scale. If the meter indication is infinity or open circuit, the coil is good. b) Connect the meter as shown in step 2. Set the meter on the ohms scale. If the meter indication is < (less than) 1 ohm, the coil is good. c) Connect the meter as shown in step 3. Set the meter on the ohms scale, 20k. If the meter indication shows infinity or open circuit the coil should be replaced.

4. Install the coil to the mounting bracket and connect the distributor wire, coil wire and engine wiring harness.

Coil Removal

! CAUTION Before starting removal steps of coil or distributor, disconnect the negative battery cable.

1. Remove coil mounting bolts and coil from the bracket.

2. Remove all wires connected to the coil.

3. Check coil for damage or broken connectors.

Ignition Sensing Coil Test

NOTE The following procedure will check the resistance of the sensing coil for the ignition module inside the distributor. The distributor can be left on the engine or removed for this test.

1. Connect an ohmmeter to either sensing coil connection and the housing as shown in step 1.

If the reading is not infinity or open, replace the sensing coil.

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2. Connect an ohmmeter to both connectors of the sensing coil as shown in step 2. Move the connectors at the sensing coil and at the connector to find any open circuits that are not constant. The ohmmeter will correctly indicate 500 to 1500 ohms. If the indication is not constant or is not within the resistance range, replace the sensing coil.

1. Remove the distributor cap from the distributor.

301393

2. Install a NEW distributor gasket onto the distributor.

IGNITSY4

Distributor Installation Important: The engine front cover has 2 alignment tabs and the crankshaft balancer has 2 alignment marks (spaced 90 degrees apart) which are used for positioning number 1 piston at Top Dead Center (TDC). With the piston on the compression stroke and at top dead center, the crankshaft balancer alignment mark (1) must align with the engine front cover tab (2) and the crankshaft balancer alignment mark (4) must align with the engine front cover tab (3).

Rotate the crankshaft balancer clockwise until the alignment marks on the crankshaft balancer are aligned with the tabs on the engine front cover and the number 1 piston is at top dead center of the compression stroke.

3. Align the indent hole on the driven gear with the paint mark.

4. Ensure that the distributor rotor segment points to the cap hold area.

492137

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5. Align the slotted tang in the oil pump driveshaft with the distributor driveshaft. Rotate the oil pump driveshaft with a screwdriver if necessary.

6. Align the flat (1) in the distributor housing toward the front of the engine.

8. Once the distributor is fully seated, align the distributor rotor segment with the number 6 pointer (1) that is cast into the distributor base.

If the distributor rotor segment does not come with a few degrees of the number 6 pointer (1), the gear mesh between the distributor and camshaft may be off a tooth or more. Repeat the procedure again in order to achieve proper alignment.

523746

7. Install the distributor and distributor clamp.

Tighten the bolt enough to hold the distributor in position, but do not tighten completely. a. Align the rotor with the mark on the distributor housing made during removal. b. Align the mark on the distributor housing and the engine made during removal.

334555

9. Install the distributor clamp bolt and tighten to the specified torque.

Tightening Torque for Distributor Clamp Bolt

2.49 Kgf•m (18 lb ft) [25 N•m]

10. If the distributor cap is not being replaced, inspect the cap for carbon build up, cracks or small holes. Replace the distributor cap if it is damaged. Install the distributor cap and NEW distributor cap bolts, tighten to the specified torque.

Tightening Torque for Distributor Cap Bolts

310298

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.24 Kgf•m (21 lb in) [2.4 N•m]

connector on the side of the distributor. Next connect the alligator clip lead from the tool to the positive (+) side of the 12 volt battery with the engine running. This will cause the engine to slow down and default the distributor to basic timing. Read the timing off the balancer pulley with the timing light. If timing is showing something other than what is shown in the engine specifications (gas or LP) section it must be adjusted. Loosen the distributor and rotate it until the correct reading is obtained. Retighten the distributor, hold down clamp, and recheck timing again.

11. Install the coil lead wire and engine harness connector to the distributor.

! CAUTION Do not shut engine off with the 12 volt lead connected to the battery or restart the engine with the timing shunt connected. Connecting the timing shunt to 12 volt + battery with the engine not running can cause damage to the ECU or the EST module.

12. Reconnect the negative battery cable.

Ignition Timing

NOTE Before trying to start the engine, make sure the distributor is installed correctly, and all high voltage wires are connected and installed correctly on the coil and distributor.

1. The ignition timing setting is different for gasoline and LPG models and there is also a year break. Units built before 2004 are set at 0° BTDC for Gasoline units or 8° BTDC for LPG units. Year 2004 and up the timing is set at 0° BTDC and the computer takes care of the timing.

IGNITSY7

➧D➧ Spark Plug Inspection Check each spark plug for the following faults. If necessary, replace the spark plug: 1. Damage to insulator.

2. Wear to electrodes.

3. Deposit of carbon. To remove carbon deposit, use a plug cleaner or wire brush. At the same time, clean the insulator tip (glass).

4. Damage to gasket.

5. Burnt insulator gasket (glass). Black carbon coating on the insulator tip is caused by too rich a fuel mixture, excessively insufficient intake air, or misfires due to excessively large plug gap.

Whitish coating on the insulator tip is caused by too thin a fuel mixture, advanced ignition timing, or loose spark plug.

6. Check the plug gap. If necessary, adjust it to specification. .889mm, .035 in. gap.

7. Do not over tighten spark plugs when replacing or inspecting them. See Torque section for values.

IGNITSY6

2. Connect an inductive type timing light on No. 1 spark plug wire.

3. Start the engine. The engine does not start rotating the distributor clockwise or counterclockwise until the engine starts. If engine still will not start, go back to the EST Distributor Installation section. Once the engine is running smoothly let it idle until the engine reaches normal operational temperature.

4. With engine running at an idle and warm, unplug the 4-wire connector on the distributor (gas only) and connect the timing shunt tool to the 4-pin

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Alternator and V-Belt (Units built before 01/01/2004) Removal and Installation

1

T= 2.49 Kgf•m (18 lb •ft) [25 N•m]

3

4

2 T= 4.16Kgf•m(30 lb •ft) [41 N•m]

5

Removal Steps 1. Bolt 2. Bolt 3. Alternator

6

4. Belt T= 5.94Kgf•m (43 lb•ft) [58 N•m]

5. Pulley 6. Pulley

T= 2.49Kgf•m (18 lb•ft) [25 N•m]

-165-

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Alternator Removal and Installation

6 5

9

8 3 2 4 1 7 14

11 13 12

10

16 15

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Removal steps 1. Nut 2. Pulley 3. Rotor Assy 4. Bearing Retainer 5. Bearing 6. Front Bracket 7. Spacer 8. Fan 9. Stator Assy 10. Condenser Assy 11. Regulator 12. Brush 13. Spring 14. Slinger 15. Rectifier Assy 16. Rear Bracket

Accessory Drive Belt Replacement

Installation Procedure 1. Route the belts over all the pulleys including the alternator.

2. Rotate alternator to tension belts and tighten mounting bolts.

Removal Procedure 1. Loosen alternator mounting bolts.

2. Rotate alternator to reduce belt tension and remove drive belt.

43858

43856

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Starter Motor Removal and Installation

6

5 4

Removal Steps

3

2 1

-169-

1.

2.

3.

4.

5.

6.

Bolt Spring Washer Starter Motor Cord Starter Harness Starter Relay

Starter Motor Testing

Troubleshooting

Electrically the motor consists of the brush assembly and the armature. The solenoid contains pull-in and hold-in windings, and the motor external wiring is the same as field-coil motors. No periodic maintenance or lubrication is required.

Cranking Circuit Before removing any unit in a cranking circuit for repair, the following checks should be made.

Battery: Ensure that the battery is fully charged, and that it passes the load test. The starting motor cannot operate properly if the battery is discharged or defective.

Wiring: Inspect the wiring for damage. Inspect all connections to the cranking motor, solenoid, ignition switch or any other control switch, and battery, including all ground connections. To eliminate any excessive resistance, disconnect and wire brush all wiring connectors in the cranking circuit. This will ensure optimum performance from the wiring. Cables, when properly attached at the battery side terminals, are sealed and normally required no periodic maintenance attention.

Switches: Inspect all switches to determine their condition. With switches closed, use a voltmeter to check the circuit for continuity. Replace defective switches and wiring as required.

Motor: If the battery, wiring and switches are in satisfactory condition, and the engine is known to be functioning properly, remove the motor and follow the test procedures outlined below.

Regardless of the construction, never operate the cranking motor more than 30 seconds at a time without pausing to allow it to cool for at least two minutes. Overheating caused by excessive cranking will seriously damage the cranking motor.

In the basic circuit, the solenoid windings are energized when the switch is closed. The resulting plunger and shift lever movement causes the pinion to engage the engine flywheel ring gear and the solenoid main contacts to close, and cranking takes place. When the engine starts, pinion overrun protects the armature from excessive speed until the switch is opened, at which time the return spring causes the pinion to disengage. To prevent excessive overrun, the switch should be opened immediately when the engine starts.

Cranking Motor Tests With the cranking motor removed from the engine, the pinion should be checked for freedom of operation by turning it on the screw shaft. The armature should be checked for freedom of rotation by prying the pinion with a screwdriver. Tight bearings or a bent armature shaft will cause the armature not to turn freely. If the armature does not turn freely the motor should be replaced.

-170-

Check Pinion Clearance 1. With motor lead disconnected from solenoid, connect 12 volt battery to solenoid “S” terminal and drive housing.

2. Momentarily flash a jumper lead from solenoid “M” terminal to drive housing. Pinion will shift into crank position.

3. Push pinion back to take up any movement, and check clearance between pinion and retainer with a feeler gauge. The clearance should be 0.010 and 0.160 in.

4. Clearance is necessary to prevent wear on drive collar during cranking. Clearance is not adjustable. If not within limits, check for improper assembly or for worn parts.

-171-

Fuel System - Gasoline (Units built before 01/01/2004) Removal and Installation

Removal steps 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

16.

17.

18.

19.

20.

21.

22.

23.

-173-

Nut Washer - Spring Washer Seal - Oil Hose Bolt Horn - Air Bolt Pipe - Fuel Hose Hose Carburetor Gasket Nut Hose Hose Adapter Gasket - Adapter Cable Lever Bracket Motor - Step Bracket - Motor

-174-

Fuel Pump and Fuel Hose (Units built before 01/01/2004) Removal and Installation

Precautions for Installation • Install the fuel pump filter side bottom.

• Put in the fuel hose securely to the nipple or joint, clamp it, and make sure that no fuel leaks.

• Fasten the fuel hose securely to prevent it from being damaged by vibrations and touching any rotating or hot part.

NOTE This manual only covers the fuel system supplied on units built before 01/01/2004. See fuel system supplements for units built after 01/01/2004.

-175-

-176-

Fuel Pump (Units built before 01/01/2004) Disassembly and Reassembly

Disassembly Steps 1. Pump cover 2. Magnet

N

3. Cover gasket

N

4. Filter

N

5. Filter gasket 6. Pump body

Main Point of Disassembly

! CAUTION The transistorized fuel pump is of the totally enclosed type, except the filter side. Ordinary service work should be restricted to inspection and cleaning of the filter; never disassemble the fuel pump unnecessarily. Do not tamper with the fuel inlet elbow. Only items (2) to (5) can be replaced independently.

1. Remove the pump cover with a 17 mm (0.67 in.) wrench. Then take out the filter. Never impact upon the pump body during removal.

-177-

Inspection Checking and Cleaning the Filter Check the filter for clogging and dirtiness. If necessary, clean or replace the filter.

Checking the Fuel Pump for Proper Function Turn the ignition switch to ON and listen for clicks.

If no click is made, connect the fuel pump directly to a 12-volt power source and try listening for clicks. Replace if no sound is found.

Checking Delivery Flow Check the pump delivery flow by using the method shown in the figure. Delivery flow of the pump is considered normal if 15-second delivery is 225 cm3.

Main Point of Reassembly Filter 1. Before installing the filter, check that the pump body side plunger valve is not clogged with dust.

2. Be sure to install a NEW filter gasket.

3. Fit the cleaned magnet to the cover without fail and install the cover securely. During trial run, check the cover and piping. For fuel leaks, use a soap/water solution or leak detector solution on all fittings while engine is running.

-178-

Fuel System - LP (Units built before 01/01/2004) Removal and Installation

2

1

N3 5 4 6

N 7 10 20

8

13

11

N 12

14

9

Removal steps 1. Nut 2. Carburetor Assy

N

3. Gasket 4. Spacer 5. Hose 6. Governor - Air

N

7. Gasket 8. Hose 9. Hose 10. Nut 11. Adapter

N

12. Gasket - Adapter 13. Actuator - Vacuum 14. Unit, Idle - Up

-179-

Maintenance Checks

5. With the carburetor air-gas valve and cover removed, it is a simple matter to check the converter and fuel lock for leaks. The following checks should indicate each component is operating properly.

• Turn fuel on at the tank and check carburetor open gas jet for leakage. If the fuel lock and the converter are operating properly, no fuel will leak through.

• Press the primer button on the front of the converter to open the gas regulator valve. A small amount of gas should pass through the jet as the system is emptied back to the fuel lock. If the fuel lock is operating properly, the gas flow will soon cease as soon as the fuel downstream of the fuel lock is exhausted.

• Next remove the vacuum hose to the VFF30 fuel lock from the fitting at the source of vacuum. With the primer button depressed, apply vacuum to the fuel lock vacuum hose.

Fuel should flow immediately and stop flowing when suction is relieved.

6. With consistent starting and idling, the vaporizer/ regulator need not be disassembled. If inconsistent, remove the regulator front cover and diaphragm assembly to check for oil and dirt deposits. If granules of foreign matter are embedded in the Viton rubber of the secondary valve, the valve and seat may be washed clean; however, it may be wise to replace the Viton valve for a perfect seal. These granules almost invariably enter the vaporizer in solution in the liquid propane and drop out as the fuel is vaporized, similar to salt water through a filter with deposits of salt left after evaporation of the water. It is seldom a sign of insufficient filtration.

Foreign matter and scale from the tank generally deposit in the filter when a new tank is installed.

Welding scale and rust are frequently present in new tanks, and occasionally residual water from the hydrostatic pressure testing is still in the tank.

At scheduled preventative maintenance increments: 1. Check coolant hoses for deterioration. Hardened hoses may crack or be subject to rupture, particularly if thermostats hotter than 160-170 degrees F are used, or if hoses are located adjacent to an exhaust manifold. Also check all vacuum hoses.

2. The fuel vapor hose is located between the vaporizer / regulator and the carburetor. Remove the hose and check for undue deterioration.

Particularly check the vapor outlet fitting from the regulator for tightness.

3. Use a soap/water solution or leak detector solution on all fittings while engine is running.

4. If starting and idling have been consistently satisfactory, it should be unnecessary to disassemble the carburetor air valve from the bowl. If inconsistent, remove the air valve cover, spring and air valve with the diaphragm. Check the gas-metering valve and gas jet for accumulation of foreign deposits or greasy substance, and clean both with a brush and kerosene or equivalent solvent as needed.

Check the air valve diaphragm for integrity and flexibility. Hold the diaphragm up against a strong light to check for small tears or pinholes.

Normal life of the diaphragm and seat is 2,000 hours, barring excessive backfiring or similar abnormalities. When reinstalling the air-gas valve assembly in the bowl, mixer models CA100, CA125 and CA225 require reinstallation of the gas-metering valve in position with two gas valve slots opposing the gas inlet flow. This is for ideal air-fuel distribution.

NOTE This manual only covers the fuel system supplied on units built before 01/01/2004. See fuel system supplements for units built after 01/01/2004.

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Vacuum Fuel Lockoff Filter (Units built before 01/01/2004)

Theory of Operations • Impco vacuum fuel locks are normally closed.

• They use air valve vacuum from the air fuel mixer to open the fuel lock.

• If the engine stops or is turned off, engine vacuum dissipates and the fuel lockoff closes automatically. This is a desirable safety feature.

• When the engine is cranking or running, air valve vacuum is transmitted from the mixer to the lockoff through a 3/16 in. vacuum hose.

• The vacuum acts upon a diaphragm assembly.

Atmospheric pressure forces it inward against the valve operating lever.

• As the valve operating lever is depressed it moves the valve operating pin.

• As the valve operating pin moves it lifts the valve off of its seat.

• This allows propane to flow through the lockoffs 10 micron filter and on to the pressure regulator.

Vacuum Fuel Lock Service Procedures • The Impco VFF30 vacuum fuel filter lockoff is fully field serviceable.

• A repair kit is available which includes all the wear parts necessary to rebuild the unit. Each part is also available individually.

• To test a unit for external leakage, apply an approved leak test solution to the entire outer surface and watch for leaks.

• To test a unit for internal leakage remove the vacuum hose from the port marked VAC. • Apply an approved leak test agent to your finger tip and lightly place finger over port marked VAC. • Position your finger so that any LPG leaking internally and escaping out of the vacuum port will create small bubbles around your fingertip.

• If bubbles are found, the pin and o-ring need replacing.

Vacuum Fuel Lock Installation Tips • Lockoffs with filter elements should be positioned so that the filter can be changed as easily as possible.

• Vacuum lockoffs should be positioned so that the atmospheric vent is not restricted.

• Vacuum lockoffs should be positioned so that debris will not enter the atmospheric vent.

• Vacuum lockoffs should be connected to air valve vacuum, not manifold vacuum.

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Model J, K and Cobra Converter / Regulator (Units built before 01/01/2004)

LPG Pressure Regulator / Converter Service Procedures

Theory of Operation This converter is a water-heated, two-stage vaporizer. Fuel enters the converter at tank pressure as a liquid and its pressure is reduced to 0.1 to 0.15 kgf/cm2 (1.4 to 2.1 psi) [10 to 15 kPa] within the primary or vaporizing chamber -- it is converted from liquid to a gas. Heat for vaporization is supplied form the engine cooling system.

• lmpco pressure regulators have proven to be very reliable and require very little maintenance due to the robustness of their design and the small number of moving parts. Only periodic disassembly for the purpose of inspection and cleaning is required. The time interval between inspections varies with the quality of the fuel being used. A quick pressure test is all that is required to verify proper regulator operation.

Repair kits are available, if required. These kits contain complete instructions and all wear parts necessary to rebuild an Impco pressure regulator.

Gas then passes through the secondary valve which is controlled by the secondary diaphragm and flows into the secondary chamber where it is drawn off through the gas outlet to the carburetor.

NOTE This manual only covers the fuel system supplied on units built before 01/01/2004. See fuel system supplements for units built after 01/01/2004.

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On-Truck Pressure Test

Regulator / Converter Bench Test

1. Shut off fuel supply at fuel storage container and run engine out of fuel.

2. Remove the primary test port plug.

3. Connect a 0-5 psi gauge to the primary test port.

4. Remove secondary test port plug.

5. Install a 0-10 inch wc (water column) gauge.

6. Slowly open fuel storage container valve.

7. Start engine.

8. Note gauge pressure readings.

9. Primary pressure should be approximately 1.5 psi.

10. Secondary pressure on regulators with a blue spring should be negative 1.5 w c.

11. Secondary pressure on regulators with an orange spring should be negative 0.5 w c.

12. Press throttle several times then allow engine to idle.

13. Gauge readings will fluctuate and then should return to normal as engine idles and pressures stabilize.

14. If pressure readings differ from those stated above, the regulator should be disassembled and inspected as outlined below in "Regulator Disassembly, Inspection, Cleaning and Assembly".

1.

2.

3.

4.

5.

6.

7.

Remove the primary test port plug.

Connect a 0-5 psi gauge to the primary test port.

Connect compressed air to the fuel inlet.

Pressurize the regulator.

Note reading on pressure gauge.

Gauge reading should be approximately 1.5 psi.

There should be no air escaping from the regulator outlet.

8. If air is escaping from the regulator outlet check the secondary diaphragm, secondary valve and seat.

9. Slowly push primer button several times and release.

10. Gauge will fluctuate but should return to approximately 1.5 psi.

Pressure Regulator / Converter Installation Tips 1. Mount regulator below top of radiator. Air in the cooling system will seek the highest point. The regulator must not be the highest point. Air trapped in the regulator may cause it to freeze.

2. Mount regulator with fuel outlet pointing down.

This allows for any heavy ends, such as butyl oil, that may be present in the fuel, to drain from the regulator. If any heavy ends are allowed to accumulate in the regulator they may interfere with the movement of the diaphragms.

3. Mount regulator to a solid surface. Fuel lines and coolant lines must not be used to support regulator.

4. Mount regulator as close as practical to the air fuel mixer. Since the regulator requires a negative pressure signal from the air fuel mixer to operate, mounting them close together will ensure short cranking time when starting the engine.

Regulator / Converter Disassembly, Inspection, Cleaning, and Assembly 1. Shut off fuel supply at fuel storage container and run engine out of fuel.

2. Disconnect fuel inlet and outlet lines.

3. Drain cooling system.

4. Remove regulator.

5. Disassemble regulator.

6. Clean primary and secondary valves with soap and warm water and inspect for wear. Replace if required.

7. Clean primary and secondary diaphragms with soap and warm water and inspect for wear.

8. Inspect primary diaphragm lever for straightness.

Replace if required.

9. Always replace the coolant chamber gasket.

10. Clean regulator castings with parts cleaning solvent and inspect. It is very rare for the castings to require replacement.

11. Reassemble regulator.

12. Use an anti-seize compound on screws.

13. Use an approved pipe sealant on fittings.

14. Bench test regulator.

Regulator/Lockout - Removal 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

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Turn off engine.

Run engine to clear LP system.

Drain coolant.

Remove battery.

Disconnect LP line at lockout.

Remove LP regulator/lockout assembly.

Remove water hoses from regulator.

Remove low pressure hose from regulator.

Remove vacuum hose from lockout.

Remove bracket from regulator/lockout.

Separate lockout from regulator.

Impco CA 100 Air Fuel Mixer

Air Valve Mixer Theory Of Operation The air-gas valve mixer is mounted in the intake air stream above the throttle plates and is designed to create a slight pressure drop (negative pressure) as air is drawn through it in to the engine. This negative pressure signal is communicated to the upperside of the diaphragm through passages in the air-gas valve assembly (the air-gas valve assembly is mounted in the center of and supported by the diaphragm).

Atmospheric pressure above the diaphragm forces it down against the secondary metering spring and opens the secondary valve allowing fuel to flow to the air-gas valve mixer. The tapered shape of the gas-metering valve is designed to maintain the correct air/fuel ratio over the entire operating range of the engine.

Atmospheric pressure acting on the underside of the diaphragm forces it upward against the metering spring. The metering spring is calibrated to generate about negative 6-inches of water column at idle and up to about negative 14-inches of water column at wide open throttle. The amount of negative pressure generated is a direct result of throttle position and the amount of air flowing through the mixer. As the diaphragm rises it lifts the tapered gas metering valve off of its seat and exposes the fuel outlet to the negative pressure generated within the mixer. This allows the negative pressure signal to travel to the secondary chamber of the pressure regulator and act upon the underside of the secondary diaphragm.

This manual only covers the fuel system supplied on units built before 01/01/2004. See fuel system supplements for units built after 01/01/2004.

NOTE

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Model CA100 Carburetor Repair Kit (Units built before 01/01/2004) Installation Instructions

1.

2.

3.

4. *5. *6. *7. *8.

9.

10.

11.

12.

13.

14.

15.

16.

17.

Screw Cover Spring, Air Valve Screw Plate, backup Diaphragm Ring, Air Valve Air Valve Mixer Body Fitting Screw, idle Spring, idle screw Plug Gasket Spacer Adaptor Air Valve Assembly

* Components included in the Repair Kit 205403

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Model CA100 Carburetor Repair Kit Installation 1. Remove the air valve cover and retaining screws.

3. Press the air valve down until it bottoms into the body.

205406 205407

4. Reassemble the air valve cover and install retaining screws.

2. Lift out and replace the air valve assembly in the mixer body.

205405

205407

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LPG Carburetor Adjustment Procedure CO/Exhaust Analyzer 1. Check engine coolant and transmission oil is at full levels, and inching pedal is properly adjusted.

2. Turn idle mixture adjustment screw all the way “in” clockwise, then turn it “out” 1-1/2 rotations.

3. Allow the engine and transmission temperature to warm up to operating temperature. Transmission temperature gauge should be just over first break line or higher.

NOTE There is a 5-10 second delay between making a power valve adjustment and picking up the effect on the analyzer. A slight change in power valve setting will produce a significant change in CO level.

NOTE Turning the power valve clockwise produces a rich mixture and higher CO levels. Turning it counterclockwise will produce a lean mixture and lower CO levels.

NOTE For console box without trans temperature gauge, warm truck up until engine coolant gauge is at block line or slightly above.

10. Remove gas collection hose.

4. Adjust low idle to 750 ± 50 rpm using low idle adjustment screw. Then check engine timing and adjust as required to specification (8°BTDC).

5. Insert gas collection hose of emission analyzer into tail pipe of truck approximately 250mm (10 in.) Do not insert during warm up.

6. Check idle adjustment with truck at low (750 ± 50 rpm) and in neutral, adjust the Idle Mixture Adjustment Screw until the co-emission level is to a maximum CO% of 0.8%.

Governor Speed Adjustment Procedure 1. Set transmission in neutral position.

2. Press the accelerator pedal all the way to full open throttle. High RPM is 2650.

3. Turn spring adjustment nut (A) clockwise to increase rpm. Turn nut counter clockwise to decrease rpm.

4. When turning nut, hold the adjusting screw (A1).

The adjusting screw is only used to adjust hunting.

NOTE Turning the screw “in” will make the fuel mixture rich, higher CO level, and turning it “out” will make it lean, lower CO level.

7. Adjust the idle screw located on the idle up vacuum device so that it contacts the plunger.

8. Check high idle RPM to make sure it is not beyond 2650. If it is adjust the governor.

9. Power adjustment -- make sure truck is adequately secured, hold at converter stall full throttle (no more than 10 seconds at a time), and adjust power valve until the CO emission level is a maximum of 1.0%.

Adjustment for Eliminating Hunting: 1. Set transmission in neutral position.

2. Press the accelerator pedal all the way.

3. Gradually turn the adjusting screw (B) clockwise until the engine no longer hunts.

! CAUTION Do not attempt to depress the inching pedal. Do not continue “stall speed” run for more than 10 seconds. A failure to follow this precaution would result in destruction of the torque converter.

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Accelerator Cable Adjustment — LPG

NOTE Adjustment of the Accelerator Cable and the Accelerator Pedal Stop Bolt is required to obtain correct engine RPM. 1. The Floor Plate must be installed and the engine cover open to view the movement of the throttle cable linkage.

2. With the engine stopped, pre adjust the tension to 2-4 mm of free play at accelerator pedal before throttle linkage begins to move. Throttle linkage and cable must be able to follow Idle Up Actuator rod when engine is running to obtain correct low Idle setting.

3. Loosen the locking nut on the accelerator pedal stop bolt to allow adjustment of the accelerator stop bolt.

4. Depress the accelerator pedal while viewing the throttle cable linkage. The linkage will move the full range of motion from the stops as the accelerator pedal is depressed.

5. Set the stop bolt height so the throttle linkage moves the full range of motion within 0-1 mm from the stop plates at carburetor. Tighten the locknut to secure the accelerator stop bolt once adjustment is obtained.

6. With the engine running and at operating temperature make final tension adjustment of 0-2 mm free play at accelerator pedal before throttle linkage begins to move. Readjust as necessary.

7. Adjust Idle Speed and Idle Mixture. Low idle 750 + - 50 rpm, High rpm 2650 – 2700 rpm.

8. Check torque converter stall speed per chassis service manual.

NOTE This manual only covers the fuel system supplied on units built before 01/01/2004. See fuel system supplements for units built after 01/01/2004.

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Special Tools and Equipment

J 3049 - A Valve Lifter Remover

J 5892 - D Valve Spring Compressor

J 5239 Connecting Rod Bolt Guide Set

J 7872 Magnetic Base Dial Indicator

J 5590 Installer

J 8001 Dial Indicator Set

J 5825 - A Crankshaft Gear Remover

J 8037 Ring Compressor

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J 8062 Valve Spring Compressor

J 9666 Valve Spring Tester

J 8087 Cylinder Bore Gauge

J 21882 Oil Suction Pipe Installer

J 8089 Carbon Removing Brush

J 23523 - F Balancer Remover and Installer

J 8092 Universal Driver Handle

J 24086 - C Piston Pin Remover/Installer

J 8520 Cam Lobe Lift Indicator

J 5830-02 Valve Guide Reamer Set

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J 24270 Cylinder Bore Ridge Reamer

J 35621 - B Rear Main Seal Installer

J 26941 Bushing/Bearing Remover

J 36660 Electronic Torque Angle Meter

J 33049 Camshaft Bearing Service Kit

J 36996 Balance Shaft Installer

J 35468 Cover Aligner/Seal Installer

J 38606 Valve Spring Compressor

90425-09120 Pulley Puller

J 38834 Balance Shaft Service Kit

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J 41712 Oil Pressure Switch Socket

Timing Shunt

J 42073 Valve Stem Seal Installer

91868-02300 ECU Diagnostic Tester

91H20-09220 Seal Cutter

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