Caterpillar GM4.3L Gasoline Engine Service Manual SN 003103 & up - PDF DOWNLOAD

99789-84100

GM4.3L Gasoline Engine 003103-up

For use with GC35K-GC70K; GP40, GPL40, GP45, GP50 Lift Trucks

Foreword This service manual is a guide to servicing of Caterpillar ® lift trucks. The instructions are grouped by system.

The long, productive life of lift trucks depends upon correct servicing as described in this service manual. Carefully read the respective sections of this manual. Know all the components before attempting to test, repair or rebuild a part or system.

This manual’s descriptions, illustrations and specifications are for trucks with these model numbers: Caterpillar GP40 and GPL40, GP45, GP50; GC35K-GC70K. Mitsubishi Caterpillar Forklift Inc. (MCFA) 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 Caterpillar lift truck dealer for the latest available information.

For items petaining to the chasis, refer to the following manuals: GC35K-70K – 99739-80100 GP40-50 – 99739-87100

N O T E C A IAO U T N !!W

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: To highlight an essential operating procedure or condition.

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

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

AR !W AR !W

The OPERATION & MAINTENANCE MANUAL outlines the proper and safe lubrication and maintenance for the machine, as recommended by Mitsubishi®.

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.

Because the service mechanic may be unfamiliar with many of the systems on this machine 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 machine 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 that should always be observed.

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

2. Always wear protective glasses and protective shoes when working around machines. In particular, wear protective glasses when pounding on any part of the machine 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 machinery.

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

4. Lower the forks or other implements to the ground before performing any work on the machine. If this cannot be done, make sure the forks or other implements are blocked correctly to prevent them from dropping unexpectedly.

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

5. Use steps and grab handles (if applicable) when mounting or dismounting a machine. Clean any mud or debris from steps, walkways or work platforms before using. Always face machine 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 machines 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, breathers and plugs on the machine. 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 machine 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 machine parked on a level, hard surface. Block the machine 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 machine. Hang “Do Not Operate” tag in the Operator’s Compartment.

14. Repairs which require welding should be performed only with the benefit of the appropriate

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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.

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.

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.

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

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.

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.

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.

Do not operate a machine 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.

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.

TABLE OF CONTENTS Sealers, Adhesives, and Lubricants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1 How to Read This Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2 Removal and Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3

Special Tools and Equipment . . . . . . . . . . . . . . . . . . . .

Use of RTV and Anaerobic Sealer (Gasket Eliminator) Determining When to Overhaul the Engine . . . . . . . . . .

Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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Precautions for Disassembly and Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9 General Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10

Engine Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13 Removal Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13 Installation Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13

Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14 Engine Specifications - Gas and LP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14 General Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17

Major Nuts and Bolts Tightening Torque . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21 Diagnostic Information and Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23 Base Engine Misfire Diagnosis Engine Compression Test . . . .

Engine Noise Diagnosis . . . . .

Valve Train Diagnosis (General)

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Valve Train Diagnosis (Noise Diagnosis) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26 Engine Mechanical - 4.3L . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29 Oil Consumption Diagnosis . . . . . . . . . . . . . .

Low or No Oil Pressure Diagnosis and Testing Oil Leak Diagnosis . . . . . . . . . . . . . . . . . . . .

Repairing the Leak . . . . . . . . . . . . . . . . . . . .

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.29 .29 .29 .30

Intake Manifold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31 Intake Manifold Removal Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31 Intake Manifold Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32

Exhaust Manifold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35 Oil Level Indicator and Tube Removal . . . . . . .

Exhaust Manifold and Heat Shields Removal . .

Exhaust Manifold Clean and Inspect . . . . . . . .

Exhaust Manifold Installation and Heat Shields Oil Level Indicator and Tube Installation . . . . . .

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Cylinder Head and Valves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38 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 . . . . . . . . . . . . . . . . . . . . .

Valve Rocker Arm and Push Rod Installation . . . .

Valve Rocker Arm Cover Left Installation . . . . . . .

Cylinder Head Installation . . . . . . . . . . . . . . . . . .

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Engine Lubrication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51

Table of Contents

Oil Pan, Pump and Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52 Oil Oil Oil Oil Oil Oil Oil Oil

Pan Removal . . . . . . . . .

Pump Removal . . . . . . .

Filter Adapter Removal . .

Pump Disassembly . . . .

Pump Assembly . . . . . . .

Filter Adapter Installation Pump Installation . . . . . .

Pan Installation . . . . . . .

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Front Cover, Timing Chain, and Crankshaft Balancer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .61 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 . . . . . . .

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Balancer and Camshaft . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .65 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 . . . . . . . . . . . . . . .

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.66 .67 .68 .68 .69 .69 .70 .70

Crankshaft, Flywheel, Rear Seal, and Bearings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .71 Engine Flywheel Removal . . . . . . . . . . . . . . . . . . .

Crankshaft Rear Oil Seal and Housing Removal . .

Crankshaft, Bearings, and Bearing Cap Removal .

Service Prior to Assembly . . . . . . . . . . . . . . . . . . .

Crankshaft, Bearings and Bearing Cap Installation Bearing Clearance Measuring Procedures . . . . . . .

Micrometer Method for Crankshaft Bearings . . . . .

Crankshaft Rear Oil Seal and Housing Installation .

Engine Flywheel Installation . . . . . . . . . . . . . . . . .

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Cylinder Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .75 Cylinder Block Cleaning .

Cylinder Block Inspection Reboring the Cylinders . .

Cylinder Block Installation

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Piston and Connecting Rod . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .83 Piston, Connecting Rod, and Bearing Removal . .

Piston and Connecting Rod Disassembly . . . . . .

Piston and Connecting Rod Cleaning and Inspect Piston Selection . . . . . . . . . . . . . . . . . . . . . . . . .

Piston, Connecting Rod and Bearing Installation .

Piston and Connecting Rod Assembly . . . . . . . . .

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Carburetor, Gasoline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .89 Carburetor Assembly (Upper) Carburetor Assembly (Lower) Carburetor Disassembly . . . .

Air Horn Disassembly . . . . . .

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Table of Contents

Carburetor Body Disassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .95 General Cleaning Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .97 Carburetor Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .97 Carburetor Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .98 Air Horn Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .100 Carburetor Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .105 Operational Adjustments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .108 Carburetor Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .108

Electrical Throttle and Governor Control System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .109 System Operation . . . .

Input/Output Interfaces Schematic . . . . . . . . . .

Method of Operation . .

Speed Control . . . . . . .

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GM 4.3L Engine ECU Diagnostic Tester . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .113 Ignition System and Distributor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .115 Ignition System - Distributor . . . . . . . . . . . .

Distributor Removal . . . . . . . . . . . . . . . . . .

Distributor Disassembly . . . . . . . . . . . . . . .

Distributor Assembly . . . . . . . . . . . . . . . . .

Spark Plug Wires and Coil Wire Removal .

Spark Plug Wires and Coil Wire Installation Coil Removal . . . . . . . . . . . . . . . . . . . . . . .

Coil Installation and Testing . . . . . . . . . . . .

Ignition Sensing Coil Testing . . . . . . . . . . .

Distributor Installation . . . . . . . . . . . . . . . .

Ignition Timing . . . . . . . . . . . . . . . . . . . . . .

Spark Plug . . . . . . . . . . . . . . . . . . . . . . . .

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Alternator and V-Belt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .123 Alternator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .124 Accessory Drive Belt Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .125

Starter Motor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .126 Starter Motor Testing . . . . . . . . . .

Troubleshooting . . . . . . . . . . . . . .

Disassembly . . . . . . . . . . . . . . . .

Component Inspection and Repair

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Fuel System - Gas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .132 Fuel Pump and Fuel Hose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .133 Fuel Pump Disassembly and Reassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .134 Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .135 Main Point of Reassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .135

Fuel System - LP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .136 Maintenance Checks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .137 Impco Model VFF-30 Fuel Lock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .138 Model J Regulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .140 LPG Pressure Regulator Service Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .140 On-Vehicle Pressure Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .141 Regulator Disassembly, Inspection, Cleaning, and Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .141 Regulator Bench Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .141 LPG Pressure Regulator Installation Tips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .141 LP Regulator/Lockout - Removal and Replacement GF40K Disassembly Steps . . . . . . . . . . . . . . . . . . . .141 Impco CA 100 Air Fuel Mixer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .142 Model CA100 Carburetor Repair Kit Installation Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .143 LPG Carburetor Adjustment Procedure-co/exhaust Analyzer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .145 Governor Speed Adjustment Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .145

Sealers, Adhesives, and Lubricants Application Balancer Shaft Driven Gear Bolt Threads Coolant Sealing Pellets Crankshaft Balancer Keyway Cylinder Head Bolt Threads 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 Threads Engine Block Oil Gallery Plug Engine Coolant Temperature (ECT) Gauge Sensor Threads Engine Oil Engine Oil Pressure Sensor Threads Engine Oil Pressure Sensor Fitting Threads Engine Oil Supplement Exhaust Manifold Bolt/ Stud Threads Expansion Cup Plug (Balance Shaft Rear Bearing Hole) Expansion Cup Plug (Camshaft Rear Bearing Hole) Distributor Module Lower Intake Manifold Bolt Threads Oil Level Indicator Tube Oil Pump Screen Tube Valve Rocker Arm Stud Threads Valve Train Component Prelube Water Pump Bolt Threads

Type of Material Threadlock Sealant Adhesive Sealant Adhesive

GM Part Number 12345382 3634621 12346141 12346004 12346141

MCFA Part Number 2I4264

Adhesive

12346141

A000000165

Adhesive

12346141

A000000165

Sealant Sealant Sealant SAE 10W30 Oil Sealant Sealant Lubricant Threadlock Sealant Sealant Heat Sink Compound Threadlock Sealant Sealant Threadlock Lubricant Sealant

12346004 12346004 12346004 12345610 5QT 12346004 12346004 1052367 12345493 12346004 12346004

2I4263 2I4263 2I4263 A000000806 2I4263 2I4263

12345382 12346004 12346004 12345493 12345501 12346004

A000000165 2I4256 A000000165

2I4256 2I4263 2I4263 5P8937 2I4264 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:

N O T E

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.

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.

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H o w t o R e a d T h i s M a n u a l S T ie h s b o k d e s c r i b e s t h e s r v i c e p r o c e d u r e s f o r t h e n g i e r m o v e d f r o m a v e h i c l e .

F o rfM p c e u o n c r n i g t h m v a l o t h e n g i f r o m t h e h i c l e a n d o n i n s p e c t i o n a n d s e r v i c n g , t(1 h a p p r i a a n u s p a l y p e p a d f r t i v u l m o d l . i(2 a n e n c e a n d S e r v i c n g P r o c e d r e • R e m o v a l S t e p s : T h p r t d i g n a t i o n u m b e r c o r e s p o n d s t o h e n u m b e r ))T A icttp rh d a g m o f t h c o m p o e n t p a r t s i p o v i d e n e a r i n t i u s r a o d i c a t m v a l t e p . fh ta e o n e a s e t i i o d e o g e t h r d to b e u d r n d g f h i n l e d c n o f m p p t .

• I n s t a l t i o n S t e p s : S p e c f e d c a i n t a l t i o n i s m p o s i b l e i n r e v r s e o r d e e n u m b e r s r o v i d e w i t h n t h e d i a g r m i n d c a t e o f r m v a l s .

O m i e d f t a l t i n p o s b l i n v s s q n c f m a n a c n s e v c g d o r m o v l s e p s . ro c;lith d ;l.th e o lu ira o -re u sb l••T N ta e ib g n isyg tb g esd p o vidn w h iS D s a s e m b l y S t e p s : h e p r t d s i g n a i o n u m b e r c o r e s p o n d s t o h e n u m b e r to iiR n ln u r a o d i c a t d i s a m b l y e p s . e a s e m b l y S t e p s : p c i f d i n c a s r a s e m b l y i s m p o s i b l e i n r e v r s e o r d e f d .

O i t e d f r e a m y s p o i b l r e v r s e o r d e o f d i t .

C lW isia fn a s c a t i o n o f M a j o r M a i n t e n a c e / S e r v i c e P o i n t s h td e n h e r r e m p s r l i v t o m a n t n a c e a n d rrA ifo v c g p o c d u r e s ( u c h a e s e n i a l i e ig txe ,Id n s a i n t a n e n d r c e s d r d v l u e s , tn m a r e g g h e s o f p t o l , t c . ) , t h a r e d o h e r s m j o r m a i t e n a a n s e i c p o i n t lB irIe p in n d n d t a i l . tsica c a s e e s e n l p o i n t s f o r m o v a l r sd ltm e .e m b y s t h e r a r e s e n t i a l p o i n t s f o r i n s t a l t i o n o r b l y .

S lIa y m b o s f o r L u b r i c a t i o n , S e a l n t s a n d G r e a s e icp A d h e v e ( m u l t i p u r o s e g r e a s e u n l e s t h e r i s a b n d o t y p p c i f d ) n fo rm o tvip m a o n c o n c e r n i g t h e l o c a t i o n s f o r l u b r i c a t o n d lo p ie tn id a f s a l n s n d h e i v e s S e a l r a d h e s v e ,b y u s g y m b , d a g m f p rt,p o re th e p a g e fio le w nth eB rE fn igeid k u ,lo trg u o tao m a iilcp ra n sm islo n flu id t a a , a n d x n . o a i c o n n e r m e o r IO tn n io s p e c n g le ycra s p e ch tio n sa to b e rcfo m ya u g sp cn ia lsco ra m a so u in g in sth ru m e n tlsw a rye o ve rd .rG e n lisn e rva ice p rlo s tp vh rio e in.n d m n u a l,p su h a se vd ib lsin te o slto n d e n ie g frp a o ld scb p fo m dra u g tu a sce vd iu cre -2-

How to Read This Manual

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 (lbf-ft) [N-m] *kgf-m (lbf-in.) [N-m] 15. Plug 16. Valve 17. Spring 18. Filter 19. Fitting 20. Valve 21. Bolt 22. Adapter - Oil Filter 23. Gasket 24. Connector 25. Gasket T = 2.08 (15) [20]

Denotes nonreusable part.

Lubricate all internal parts with engine oil during reassembly

INSTALLATION OR REMOVAL SERVICE POINTS A Install the oil pump screen.

• 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 MCF-1071 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.

T = 9.14 (66) [90]

T = 1.22 (106) [12]

Denotes tightening torque.

T = 2.49 (18) [25] T = 2.49 (18) [25]

T = 2.49 (18) [25]

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.

-3-

N O T E

Special Tools and Equipment All special service tool part numbers beginning with MCF- can be found in the new dealer SERVICE TOOL AND EQUIPMENT CATALOG/MANUAL MCF-5000. The catalog contains a wide assortment of tools and equipment used to service the lift truck. Information on ordering, warranty, and repair will be covered in the SERVICE TOOL AND EQUIPMENT CATALOG/MANUAL. Contact SPX/OTC Service tool department at 1-800-533-0492

MCF - 1078 or J 3049 - A Valve Lifter Remover

MCF - 1089 or J 5892 - D Valve Spring Compressor

MCF - 1064 or J 5239 Connecting Rod Bolt Guide Set

MCF - 1091 or J 7872 Magnetic Base Dial Indicator

MCF - 1065 or J 5590 Installer

MCF - 1067 or J 8001 Dial Indicator Set

MCF - 1066 or J 5825 - A Crankshaft Gear Remover

MCF - 1068 or J 8037 Ring Compressor

-4-

Special Tools and Equipment

MCF - 1069 or J 8062 Valve Spring Compressor

MCF - 1082 or J 9666 Valve Spring Tester

MCF - 1079 or J 8087 Cylinder Bore Gauge

MCF - 1071 or J 21882 Oil Suction Pipe Installer

MCF - 1092 or J 8089 Carbon Removing Brush

MCF - 1086 or J 23523 - F Balancer Remover and Installer

MCF - 1070 or J 8092 Universal Driver Handle

MCF - 1083 or J 24086 - C Piston Pin Remover/Installer

MCF - 1080 or J 8520 Cam Lobe Lift Indicator

-5-

Special Tools and Equipment

MCF - 1084 or J 24270 Cylinder Bore Ridge Reamer

MCF - 1073 or J 35621 - B Rear Main Seal Installer

MCF - 1096 or J 26941 Bushing/Bearing Remover

MCF - 1074 or J 36660 Electronic Torque Angle Meter

MCF - 1093 or J 33049 Camshaft Bearing Service Kit

MCF - 1075 or J 36996 Balance Shaft Installer

MCF - 1085 or J 35468 Cover Aligner/Seal Installer

MCF - 1090 or J 38606 Valve Spring Compressor

MCF - 1076 or J 38834 Balance Shaft Service Kit

-6-

Special Tools and Equipment

MCF - 1097 or J 41712 Oil Pressure Switch Socket

MCF - 1094 Timing Shunt

MCF - 1087 or J 42073 Valve Stem Seal Installer

MCF - 1101 or 91868-02300 ECU Diagnostic Tester

-7-

Use of RTV and Anaerobic Sealer (Gasket Eliminator)

Determining When to Overhaul the Engine

1. Apply RTV to one of the clean surfaces. Use a bead size as specified in the procedure. Run the bead to the inside of any bolt holes. Do not allow the sealer in any bolt holes. Do not allow the sealer in any blind threaded holes, as it may prevent the bolt from seating properly or cause damage when the bolt is tightened.

2. Assemble components while RTV is still wet (within 3 minutes). Do not wait for RTV to skin over.

3. Tighten bolts to specifications. Do not overtighten.

4. Apply a continuous bead of gasket eliminator to one flange. Surfaces to be resealed must be clean and dry.

Deciding when to overhaul the engine is determined by considering the following factors: A drop in compression pressure as well as an increase in lube oil consumption and excessive blowby.

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.

N O T E

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.

Important: Incorrect shimming of anaerobic sealed joints may occur when joints are partially torqued and allowed to cure more than five minutes.

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

5. Spread the bead evenly with a finger to get a uniform coating on the complete flange.

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.

-8-

Precautions

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 project and lubricate the surfaces on initial operation. Throughout this section, it should be understood that proper cleaning and protection of machined surfaces and friction areas are part of the repair procedure. This is considered standard shop practice, even if not specifically stated.

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.

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 surfaced as when removed.

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.

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

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.

Assembly

-9-

Precautions

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 Mitsubishi 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.

-10-

Precautions

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, put the plug into the socket until it clicks.

-11-

Precautions

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).

-12-

N O T E

Engine Replacement

6. Support engine using appropriate sling and hoist.

Use existing lift eyes.

7. Disconnect the fuel line and fuel line clamp.

8. Remove the starter. Refer to Engine Electrical.

9. Disconnect the torque convertor bolts from the flywheel.

10. Remove the oil filter.

11. Support the transmission with a jack.

12. Remove the transmission 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 machine.

Removal Procedure

If the engine is damaged internally and a new engine assembly is installed in the machine, ensure that all foreign material is flushed out of the cooling system. It is necessary to flush out the oil cooler system. Failure to rid the oil cooler system of debris can result in engine damage.

N O T E

1. Disconnect battery.

2. Raise the machine and support with stands.

3. Drain fluids and oil filter removal 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. Disconnect the exhaust pipe from the exhaust manifolds.

5. Disconnect the following items: • The wiring harnesses • The throttle cable • The fuel lines

Installation Procedure

If the engine is damaged internally and a new engine assembly is installed in the machine, ensure that all foreign material is flushed out of the cooling system. It is necessary to flush out the oil cooler system. Failure to rid the oil cooler system of debris can result in engine damage.

1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

16.

17.

-13-

Raise the machine.

Install the engine into the machine.

Install the left upper transmission to engine bolt.

Install the front engine mounts.

Install the distributor.

Install the following items: • The wiring harnesses • The vacuum lines • The throttle cable • The fuel lines Install torque convertor to flywheel bolts.

Install the remaining transmission to engine bolts.

Install the oil filter.

Install the pump drive shaft.

Install the starter. Refer to Engine Electrical.

Connect the fuel line and fuel line clamp.

Connect the exhaust pipe to the exhaust manifolds.

Lower the machine.

Fill the crankcase with oil.

Fill radiator with coolant.

Connect battery.

Specifications Engine Specifications - Gas and LP Application

Specification

Engine Engine Model

GM 4.3L

Manufacturer

General Motors

Type

Gasoline

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)

101.6x88.39 (4.00x3.48)

Displacement, cc (cu in)

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

710x620x740 (28x24.5x29)

Weight, kg (lbs)

260 (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

-14-

Specifications

Engine Specifications - Gas and LP, continued

Specification

Application 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 #41 - 932

Manufacturer

AC Delco

Size, mm

14 (0.55)

Gap, mm (in)

1.52 (.060)

Fuel System Carburetor/ Mixer-Type Manufacturer Governor -

Type Manufacturer

Fuel Pump -

GAS

LP

IFZ

CA100

AISAN Kogyo Co.

IMPCO

Electronic

Pneumatic

Mitsubishi Heavy Industries

Type Manufacturer

AISAN Kogyo Co.

Electromagnetic

–

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)

-15-

Specifications

Engine Specifications - Gas and LP, continued

Specification

Application Cooling System Type

Forced Circulation

Complete Engine Refill Capacity, Liter (Quarts) Water Pump

18.2 (4.84) Centrifugal Type, V - Belt Driven

Thermostat Type/ Opening Temp° F

Wax Type / 180

Alternator Type

3 - Phase AC

Manufacturer

MANDO

Rated Output, V - A

12 - 50

Regulator

Built in IC Type

Type

Electromagnetic

Starter

Manufacturer

Delco Remy

Voltage - Output, V - kW

12 V - 0.75

-16-

Specifications

General Specifications Application

Specification

Engine type

90 Degree V6

RPO VIN Code

L35(W), LF6 (X)

Displacement

4.3L

262 CID

Bore

101.6 (4.000)

Stroke

88.39 (3.480)

Compression Ratio

9.2:1

Firing Order

1-6-5-4-3-2

Spark Plug Gap

1.52 (060)

Oil Pressure (Minimum Hot)

41.4 at 1000 min. (6.0 at 1000)

- kPa at engine RPM (psi at engine RPM)

124.1 at 2000 (18.0 at 2000)

Service Weight (KG) [LB]

(185) [408]

Ignition Timing BTDC (LP) [Gasoline]

(8°) [0°]

Lubrication System Oil Capacity Without Filter Change - liters(qts.)

Oil Capacity With Filter Change Add - liters(qts.)

3.75 (4) 0.398 (0.42)

Pan Engine Block Clearance Tolerance

0.254 (0.010) max.

Cylinder Head Surface Flatness

0.1016 (0.004) max.

Exhaust Manifold Surface Flatness

0.254 (0.010) max.

Intake Manifold Surface Flatness

0.254 (0.010) max.

Cylinder Bore Diameter

101.618-101.643 (4.0007-4.0017)

Out-of-Round Production

0.02 (0.0001) max.

Out-of Round Service Limit

0.05 (0.002) max.

N O T E

Taper Production Thrust Side

0.012 (0.0005) max.

Important: All measurements are in millimeters (inches) unless otherwise noted.

-17-

Specifications

General Specifications, continued Application

Specification

Taper Production Relief Side

0.025 (0.001) max.

Taper Service Limit

0.025 (0.001) max.

Piston Piston Bore Clearance-Production

0.0001-0.005 (0.0007-0.002)

Piston Bore Clearance-Service Limit

0.070 (0.0024) max.

Piston Rings (End Gap Measured in Cylinder Bore) Piston Compression Ring Groove Clearance-Production Top

0.050-0.15 (0.02-0.06)

Piston Compression Ring Groove Clearance-Production 2nd

0.10-0.20 (0.04-0.08)

Piston Compression Ring Groove Clearance-Service Limit

0.050-0.107 (0.0127-0.0042) max.

Piston Compression Ring Gap-Production Top

0.25-0.40 (0.010-0.016)

Piston Compression Ring Gap-Production 2nd

0.46-0.66 (0.018-0.026) max.

Piston Compression Ring Gap-Service Limit

.25 - .88 (0.06 - .035) max.

Piston Oil Ring Groove Clearance-Production

0.051-0.17 (0.002-0.007)

Piston Oil Ring Groove Clearance-Service Limit

0.051-0.20 (0.002-0.008) max.

Piston Oil Ring Gap-Production

0.003-0.0127 (0.015-0.050)

Piston Oil Ring Gap-Service Limit

0.25-1.65 (0.009-0.065) max.

Piston Pin Diameter

23.545-23.548 (0.9267-0.9271)

Clearance in Piston-Production

0.009-0.0024

Clearance in Piston-Service Limit

0.0025 (max.) (0.001) max.

Fit in Connecting Rod

0.021-0.040 (0.0008-0.0016)

(0.0002-0.0007)

Interference Crankshaft Crankshaft Journal-Diameter #1

62.199-62.217 (2.4488-2.4495)

Crankshaft Journal-Diameter #2, #3

62.191-62.215 (2.4485-2.4494)

N O T E

Important: All measurements are in millimeters (inches) unless otherwise noted.

-18-

Specifications

General Specifications, continued

Application

Specification

Crankshaft Journal-Diameter #4

62.179-62.203 (2.4479 - 2.4489)

Crankshaft Journal Taper-Production

0.0076 (0.0003) max.

Crankshaft Journal Out-of-Round-Production

0.005 (0.0002) max.

Crankshaft Journal Out-of-Round-Service Limit

0.025 (0.001) max.

Crankshaft Bearing Clearance-Production #1

0.020-0.050 (0.0008-0.0020)

Crankshaft Bearing Clearance-Production #2, #3, #4

0.22-0.061 (0.0009-0.0024)

Crankshaft Bearing Clearance-Service Limit #1

0.025-0.05 (0.0010-0.0020)

Crankshaft Bearing Clearance-Service Limit #2, #3, #4

0.025-0.06 (0.0010-0.025)

Crankshaft End Play

0.050-0.20 (0.002-0.008)

Crankshaft Runout

0.025 (0.001) max.

Connecting Rod Connecting Rod Journal Diameter

57.116-57.148 (2.2487-2.2497)

Connecting Rod Journal Taper-Production

0.007 (0.0003)

Connecting Rod Journal Taper-Service Limit

0.025 (0.001)

Connecting Rod Journal Out-of-Round-Production

0.007 (0.0002)

Connecting Rod Journal Out-of-Round-Service Limit

0.025 (0.001)

Rod Bearing Clearance-Production

0.038-0.078 (0.0015-0.0031)

Rod Bearing Clearance-Service Limit

0.025-0.076 (0.0010-0.0030)

Rod Side Clearance

0.15-0.44 (0.006-0.017)

Camshaft Journal Diameter

47.452-47.478 (1.8682-1.8692)

End Play

0.0254-0.2286 (0.001-0.009)

Lobe Lift Intake

0.0726-0.0736 (0.286-0.290)

Lobe Lift Exhaust

0.0741-0.0751 (0.292-0.296)

Balance Shaft Front Bearing Journal Diameter

55.985-55.001(2.1648-2.1654)

N O T E

Rear Bearing Journal Diameter

38.084-38.100 (1.4994-1.500)

Rear Bearing Journal Clearance

0.0254-0.09144 (0.001-0.0036)

Important: All measurements are in millimeters (inches) unless otherwise noted.

-19-

Specifications

General Specifications, continued Application

Specification

Valve System Valve Lifter

Hydraulic Roller Type

Valve Rocker Arm Ratio

1.50:1

Valve Lash

Net Lash No Adjustment

Face Angle

45 Degrees

Seat Angle

46 Degrees

Seat Runout

0.05 (0.002) max.

Seat Width Intake

0.76-1.27 (0.030-0.050)

Seat Width Exhaust

1.651-2.489 (0.065-0.098)

Stem Clearance Production Intake

0.025-0.069 (0.0011-0.0027)

Stem Clearance Production Exhaust

0.025-0.069 (0.0011-0.0027)

Stem Clearance Service Limit Intake

0.0257 (0.001) max.

Stem Clearance Service Limit Exhaust

0.0508 (0.002) max.

Valve Spring Free Length

52 (2.03)

Valve Spring Pressure Closed - N at mm / (Lb at in.)

338-374 at 43 (76-84 at 1.78)

Valve Spring Pressure Open - N at mm / (Lb at in.)

832-903 at 32 (187-203 at 1.27)

Valve Spring Installed Height Intake

45.2 (1.78)

Valve Spring Installed Height Exhaust

45.2-43.43 (1.690-1.710)

N O T E

Valve Lift Intake

10.51 (0.414)

Valve Lift Exhaust

10.87 (0.428)

Important: All measurements are in millimeters (inches) unless otherwise noted.

-20-

Major Nuts and Bolts Tightening Torque

N O T E

Important: Unless otherwise noted all torques are dry.

-21-

Major Nuts and Bolts Tightening Torque

Major Nuts and Bolts Tightening Torque, continued

N O T E

Important: Unless otherwise noted all torques are dry.

-22-

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 page 113.

-23-

Diagnostic Information and Procedures

Base Engine Misfire Diagnosis, continued

Perform a cylinder leakdown test.

Ste

Using a water spray bottle, lightly spray the spark plug wires and the distributor while listening to the engine.

Did the engine stumble or fail?

-24-

Diagnostic Information and Procedures

Engine Compression Test

Knocks Cold and Continues for 2 to 3 Minutes: • Loose or broken crankshaft balancer or drive pulleys. Tighten or replace as necessary.

• Excessive piston to bore clearance.

Complete the following steps to perform a compression test: 1. Conduct the following steps to check cylinder compression. a. Engine should be at room temperature. b. Disconnect the Battery terminal and the terminal connector from the distributor. c. Remove the spark plugs. d. Block the throttle body plate wide open. e. Battery should be at or near full charge.

2. For each cylinder, crank engine through four compression strokes.

3. The lowest reading cylinder should not be less than 70% of the highest.

4. No cylinder reading should be less than 689 kPa (100 psi).

Replace the piston: • Cold engine knock usually disappears when the specific cylinder secondary ignition circuit is grounded out. Cold engine piston knock which disappears in 1.5 minutes should be considered acceptable.

Knocks on Start-Up but only Lasts a Few Seconds: • Improper oil viscosity. Install recommended oil viscosity for expected temperatures.

• Excessive piston to bore clearance.

• Excessive piston pin to piston clearance.

• Excessive crankshaft end clearance.

• Excessive crankshaft bearing clearance.

N O T E

Knocks at Idle Hot: • Detonation or spark knock. Check operation of ignition controls.

• Loose torque converter bolts • Exhaust leak at manifold. Tighten the exhaust manifold bolts and/or replace the gasket.

• Excessive connecting rod bearing clearance.

Replace bearings as necessary.

• Excessive piston pin clearance.

• Excessive crankshaft thrust bearing clearance.

• Bent connecting rod.

Important: The results of a compression test will fall into one of the following categories.

1. Normal - Compression on each cylinder builds up quickly and evenly to specified compression.

2. Piston Rings - Compression low on first stroke.

Tends to build up on the subsequent strokes but does not reach normal. Improves considerably with addition of oil.

3. Valves - 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.

Valve Train Diagnosis (General) A light tapping at one-half engine speed, or any varying frequency, can indicate a valve train problem.

These tapping noises increase with engine speed.

Before attempting to judge the valve train noises, thoroughly warm up the engine to bring all engine components to a normal state of expansion. Also, run the engine at various speeds and listen for engine noise while sitting in the driver's seat. The causes of the valve train noise include the following conditions.

Engine Noise Diagnosis There are four steps to diagnosing engine noise.

Determine the following conditions: • Type of noise.

• The exact operating condition under which the noise exists.

• The noise’s rate and location in the engine.

• Compare to sounds in other engines to make sure a normal condition is not corrected.

• Identify the type of noise. For example, a light rattle or low rumble.

• • • • • • • • • •

Remember, engine noises are generally synchronized to either engine speed (caused by the crankshaft, connecting rods or pistons) or one-half engine speed (valve train noise). Try to determine the rate at which the noise is occurring.

-25-

Low oil pressure Loose valve rocker arm attachments Worn valve rocker arm and/or pushrod Broken valve spring Sticking valves Lifters worn, dirty or faulty Camshaft lobes worn Worn valve guides Worn or damaged valve keys Bent pushrods

Valve Train Diagnosis (Noise Diagnosis) Momentary Noise On Engine Startup

This condition is normal. Oil drains from the lifters which hold the valves open when the engine is not running. The lifter needs a few seconds to fill with oil after the engine is started.

_

Intermittent Noise at Idle Speed

1. Disassemble the hydraulic lifters.

2. Check the lifters for any dirt. Check the lifters for a pitted or damaged check ball.

Are the lifters dirty? Are the lifters damaged?

Noise at Slow Idle

S Ste

Inspect valve lifter for high leakdown rate. Does the lifter have a high leakdown rate?

Lifters Noisy at High Speeds, Quiet at Low Speeds

Check for a high engine oil level. An oil level above the FULL mark causes the crankshaft counterweights to chum the oil into foam. When the foam is pumped into the lifters, the lifters become noisy. A solid column of oil ensures proper operation. Is the oil level too high?

_

Check for a low engine oil level. An oil level below the ADD mark causes the oil pump to pump air at high speeds. This causes noisy lifters. Is the oil level too low?

_

-26-

Valve Train Diagnosis (Noise Diagnosis)

Noise at Idle, Becomes Louder at High Engine Speed

This noise is not connected with lifter malfunction. The noise becomes noticeable at 1500 rpm. The noise simulates a “ticking” sound. At slow idle, the sound may be entirely gone or become a light ticking noise in one or more valves. The noise is caused by one or more of the following: 1. Badly worn or scuffed valve tip and rocker arm pad.

2. Excessive valve stem-to-guide clearance.

3. Excessive valve seat runout.

4. Off-square valve spring.

5. Excessive valve face runout.

Are any components damaged or worn excessively?

_

Ste -27-

Valve Train Diagnosis (Noise Diagnosis)

Valve Noise Regardless of Engine Speed

Check for excessive valve lash. To check for valve lash, turn the engine so that the piston in the cylinder is on top dead center (TDC) of the firing stroke. If valve lash is present, move the push rod freely up and down with the rocker arm held against the valve. Check for worn push rod upper end ball.

Is the push rod upper end ball worn?

_

Ste

If there is no need to replace the push rod or the rocker arm, this indicates trouble in the hydraulic lifter or camshaft.

Is the camshaft worn or damaged?

-28-

_

Engine Mechanical-4.3L

Oil Leak Diagnosis

Oil Consumption Diagnosis

Most fluid oil leaks are easily located and repaired by visually finding the leak and replacing or repairing the necessary parts. On some occasions a fluid leak may be difficult to locate or repair.

Excessive oil consumption (not due to leaks) is the use of 1.9L (2qts) or more of engine oil within 50 - 60 hours. The causes of excessive oil consumption include the following conditions: • External oil leaks. Tighten bolts and/or replace gaskets and oil seals as necessary.

• Incorrect oil level or improper reading of oil level indicator. With the machine on a level surface, allow adequate drain time and check for the correct oil level.

• Improper oil viscosity. Use recommended SAE viscosity for the prevailing temperatures.

• Continuous high speed driving and/or severe usage.

• Crankcase ventilation system restrictions or malfunctioning components.

• Valve guides and/or valve stem oil seals are worn or the seal is omitted.

• Piston rings broken, improperly installed, worn, or not seated properly. Allow adequate time for rings to seat. Replace broken or worn rings as necessary.

• Piston improperly installed or mis-fitted.

Use the following steps to find the leak.

1. Identify the fluid, determine whether it is engine oil or automatic transmission fluid.

2. From what point is the fluid leaking?

After running the machine at normal operating temperature, park the machine over a large sheet of paper. After a few minutes, the approximate location of the leak should be identified by the location of the drops on the paper.

3. Visually check around the suspected component.

Check around the gasket mating surfaces for leaks.

A mirror is useful for finding leaks in areas that are hard to reach.

4. If the leak still cannot be found, it may be necessary to clean the suspected area with a degreaser, steam, or spray solvent. Clean the area well, then dry the area. Operate the machine for several miles at normal operating temperature and varying speeds. After operating the machine, visually check the suspected component. If the leak is not located, try using the powder or blacklight-and-dye method.

Low or No Oil Pressure Diagnosis and Testing • • • • • • • • • • • •

Perform the following steps to use the powder method.

1. Clean the suspected area.

2. Apply aerosol-type powder (such as foot powder) to the suspected area.

3. Operate the vehicle under normal operating conditions.

4. Visually inspect the suspected component. Trace the leak path over the white powder surface to locate the source.

Low oil level. Fill to full mark on oil level indicator.

Incorrect or malfunctioning oil pressure switch.

Incorrect or malfunctioning oil pressure gauge.

Improper oil viscosity for the expected temperature.

Oil pump worn or dirty.

Malfunctioning oil pump pressure regulator valve.

Plugged oil filter.

Oil pump screen loose, plugged, or damaged.

Excessive bearing clearance. Replace as necessary.

Cracked, porous or restricted oil galleries. Repair or replace block.

Oil gallery plugs missing or incorrectly installed.

Install plugs or repair as necessary.

Oil diluted by moisture or unburned fuel mixtures.

Perform the following steps in order to use the blacklight-and-dye method.

Tools Required • J 39400 Leak Detector 1. Pour specified amount of dye onto the leaking component.

2. Operate the vehicle under normal operating conditions as directed by the J 39400.

3. Direct the light toward the suspect area. The dyed fluid will appear as a yellow path leading to the source.

-29-

Engine Mechanical-4.3L

Repairing the Leak Once the origin of the leak has been pinpointed and traced to its source, the cause of the leak must be determined to properly repair it. If a gasket is replaced, but the sealing surface is damaged, the new gasket will not repair the leak. The surface must be repaired or replaced. Before attempting to repair a leak, be sure the gasket and sealing surfaces are correct.

Perform the following steps to check for gasket leaks.

1. Inspect the fluid level/pressure to see if it is too high.

2. Check the crankcase ventilation system for restrictions or malfunctioning components.

3. Inspect for improperly tightened fasteners or dirty/damaged threads.

4. Look for warped flanges or sealing surfaces.

5. Check for scratches, burrs, or other damage to the sealing and shaft surfaces.

6. Look for a damaged or worn gasket.

7. Check for cracking or porosity of the component.

8. Check for use of an improper sealant used (where applicable).

9. Check for a damaged O-ring seal bore (scratched, burred or nicked).

10. Check for improper component installation.

11. Check for a loose or worn bearing which may lead to premature oil seal wear.

-30-

Intake Manifold Removal and Installation

1

2

Torque Specifications First pass: .31 kgf•m (27 lbf•in) [3 N•m] Second pass: 1.22 kgf•m (106 lbf•in) [12 N•m] Third pass: 1.52 kgf•m (11 lbf•ft) [15 N•m]

3

4

Removal steps

B A

1. Cover - Thermostat 2. Gasket 3. Thermostat 4. Manifold 5. Gasket

5

-31-

Intake Manifold

N O T E

Intake Manifold Removal Procedures

Important: Make sure the ends of the fuel system are properly sealed.

1. Drain the engine coolant.

2. Remove the distributor clamp and bolt.

3. Remove the distributor.

N O T E

11. Remove the gaskets.

A Intake Manifold Installation

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 MCF P/N A000000165 (GM P/N 12346141) or equivalent to each side of the cylinder head side of the intake manifold gasket.

34403

4.

5.

6.

7.

8.

9.

10.

Remove Remove Remove Remove Remove Remove Remove

the air inlet duct. the throttle linkage. the ignition coil.

PCV valve and vacuum hoses. the lower intake manifold bolts. the lower intake manifold. the intake manifold.

-32-

N O T E N O T E

Intake Manifold

Important: The lower intake manifold must be installed and the fasteners tightened while the adhesive is still wet to the touch.

2. Install the intake manifold gasket onto the cylinder heads. Use the gasket locator pins to properly seat the intake manifold gasket on the cylinder heads.

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.

3. Apply a 5 mm (0.197 in.) bead of adhesive MCF P/N A000000165 (GM P/N 12346141) or equivalent to the front and rear top of the engine block. a. Extend the adhesive bead 13 mm (0.50 in.) onto the intake manifold gasket. Front and rear top of the engine block.

b. Install the intake manifold on to engine block. c. Apply threadlock MCF P/N 2I4264 (GM P/N 12345382) or equivalent to the threads of the lower intake manifold bolts.

4. Install the lower intake manifold bolts in sequence and torque in the 3 step method.

-33-

Intake Manifold

N O T E

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.

Tightening torque for intake manifold

1st pass 3 Kgf•cm (27lbf•in) [3N•m] 2nd pass 1.22 Kgf•cm (106lbf•in) [12N•m] 3rd pass 1.62 Kgf•cm (11lbf•in) [15N•m]

-34-

Exhaust Manifold Removal and Installation

Torque Specifications: First pass: 1.52 kgf•m (11 lbf•ft) [15 N•m] Final pass: 3.05 kgf•m (22 lbf•ft) [30 N•m]

Removal steps

A B

1. Gauge - Oil 2. Tube - Level Gage 3. Shield - Exhaust 4. Shield - Spark Plug 5. Shield - Spark Plug 6. Manifolds - Exhaust

-35-

Exhaust Manifold

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.

1. Clean the exhaust manifold in solvent. a. Dry the exhaust manifold with compressed air. b. Inspect the exhaust manifold sealing surfaces for damage. c. Use a straight edge and a feeler gage and measure the exhaust manifold-to-cylinder head sealing surface for warpage. Exhaust manifold flanges with warpage in excess of 0.254 mm (0.010 in.) must be replaced.

Exhaust Manifold Installation and Heat Shields 1. Install the exhaust manifold.

2. Install the heat shields.

B Exhaust Manifold and Heat Shields Removal 1. Remove the studs and the bolts from the exhaust manifold and heat shields.

2. Remove the exhaust manifold and heat shields.

3. Use MCF P/N 2I4256 (GM P/N 12345382) threadlock on bolts, nuts, and studs before installing.

-36-

Tightening torque Front exhaust bolts

1.52 Kgf•m (11lbf•in) [15N•m]

Tightening torque rear exhaust bolts

3.05Kgf•m (22lbf•ft) [30N•m]

Exhaust Manifold

B Oil Level Indicator and Tube Installation 1. Clean and inspect the tube and indicator for damage or serviceability.

2. Apply a sealer MCF P/N 2I4256 (GM P/N 12345493) or equivalent around the oil level indicator tube 13 mm (0.5 in.) below the bead.

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 right cylinder head.

Tightening torque oil level indicator tube bolt

1.22Kgf•m (106lbf•in) [12N•m]

5. Install the oil level indicator into the tube.

-37-

Cylinder Head and Valves Removal and Installation

Removal steps 1. Rocker Arm Cover 2. Bolts A 3. Cylinder Head Assy 4. Gasket B 5. Nut 6. Rocker Arm 7. Key 8. Cap 9. Spring 10. Seal 11. Valves

1

Torque Specifications For Final Pass: Long Bolts: 75 degrees Medium Bolts: 65 degrees Short Bolts: 55 degrees

T = 2.49 kgf•m (18 lbf•ft) [25N•m]

7 5

3 2

Lo ng

8

9 M ed iu m

6

Sh or t

10

3

11 T = 4.16 kgf•m (30 lbf•ft) [40 N•m]

-38-

Cylinder Head and Valves

3.

4.

5.

6.

Valve Rocker Arm Cover Removal (Left) 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.

Remove Remove Remove Remove

the the the the

crankcase vent tube. starter relay. oil level indicator tube. valve rocker arm cover.

Valve Rocker Arm and Push Rod Removal 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 • The valve rocker arm balls • The valve rocker arms

6. Remove the rocker arm cover. Discard the old gasket.

3. Remove the valve rocker arm stud.

Valve Rocker Arm Cover Removal (Right) 1. Disconnect the negative battery cable.

2. Disconnect the spark plug wires from the spark plugs.

-39-

Cylinder Head and Valves

4. Remove the valve pushrods.

2. Remove the valve lifter guides.

5. Place the following parts in a rack so they can be reinstalled in their original locations: • The valve rocker arms • The valve rocker arm balls • The valve pushrods

3. Place the components in a rack so they can be reinstalled to their original location.

N O T E

Important: Some valve lifters may be stuck in their bores because of gum or varnish deposits. Use the MCF-1078 (J 3049) or the J 9290-01 to remove these valve lifters.

4. Use the MCF-1078 (J 3049) to remove the valve lifters.

Valve Lifter Removal Tools Required • MCF-1078 (J 3049) Valve Lifter Remover (Plier Type) • J 9290-01 Valve Lifter Remover (Slide Hammer Type) 1. Remove the valve lifter guide retainer and bolts.

-40-

Cylinder Head and Valves

5. If the valve lifters cannot be removed with the MCF-1078 (J 3049), use the J 9290-01 to remove the valve lifters.

2.

3.

4.

5.

Remove the valve rocker arms.

Remove the spark plugs.

Install the J 23590.

Apply compressed air to hold the valves in place.

Valve Stem Oil Seal and Valve Spring Removal

6. Install the valve rocker arm nut.

7. Use the MCF-1089 (J 5892-D).

Tools Required • J 23590 Spark Plug Adapter • MCF-1089 (J 5892-D) Valve Spring Compressor • MCF-1090 (J 38606) Valve Spring Compressor MCF-1089 (J 5892-D)

8. Use the MCF-1090 (J 38606) if clearance does not permit use of MCF-1089 (J 5892-D).

1. Remove the valve rocker arm cover.

-41-

Cylinder Head and Valves

2. Remove the exhaust manifold.

3. Remove the following components from the left cylinder head: • The electrical connector at the coolant temperature sensor • Spark plugs

MCF-1090 (J 38606)

9. Remove the valve keys.

10. Carefully release the valve spring tension.

11. Remove the MCF-1089 (J 5892-D) or MCF-1090 (J 38606).

12. Remove the cap, rotator, and spring.

13. Remove the valve seal.

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.

-42-

Cylinder Head and Valves

6. Remove valve arm and push rods.

8. Remove the gasket.

7. Remove cyclinder head.

-43-

Cylinder Head and Valves

Cylinder Head Disassembly and Assembly

Assembly Tools Required • MCF-1069 (J 8062) Valve Spring Compressor • MCF-1087 (J 42073) Valve Stem Oil Seal Installer 1. Clean the valve spring seat area.

2. Install the valve into the proper port.

Disassembly Tools Required • MCF-1069 (J 8062) Valve Spring Compressor 1. Use MCF-1069 (J 8062) to compress the valve springs.

N O T E N O T E

MCF-1069 (J 8062)

Important: In order for tool MCF-1087 (J 42073) to work properly, the valve is installed into the cylinder head.

N O T E

3. Lubricate guide and valve stem oil seal (3) with clean engine oil.

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.

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.

MCF-1087 (J 42073)

-44-

Cylinder Head and Valves

N O T E

5. Place the MCF-1087 (J 42073) over the valve stem and oil seal. Lightly tap on the MCF-1087 (J 42073) until the tool bottoms out against the valve spring seat.

6. Install the valve spring (4).

10. Measure the valve spring installed height from the valve spring seat to the locating surface on the cap.

MCF-1069 (J 8062)

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).

Cylinder Head Clean and Inspect Tools Required • MCF-1082 (J 9666) Valve Spring Tester • MCF-1067 (J 8001) Dial Indicator Set 1. Use the MCF-1092 (J 8089) to clean the carbon from the combustion chambers and the valve parts. Be careful not to scuff the chamber.

7. Install the cap (2) on the valve stem.

8. Use the MCF-1069 (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 MCF-1069 (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.

MCF-1092 (J 8089)

-45-

Cylinder Head and Valves

2. Clean the following areas.

• The carbon and the sludge from the valve pushrods and the valve rocker arms • The valve stems and heads on a buffing wheel • The cylinder head and engine block gasket surfaces • The bolt hole threads in the cylinder heads and the engine block 3. Inspect the following areas.

• The cylinder head for cracks in the exhaust ports and combustion chambers • The cylinder head for external cracks in the water chamber • The valves for burned heads, cracked faces, or damaged stems • The valve springs for squareness 4. Use the MCF-1082 (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.).

5. Measure the valve stem-to-bore clearance.

• Excessive valve stem-to-bore clearance will 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.

• Clamp the MCF-1067 (J 8001) on the exhaust port side of the cylinder head.

• 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.

• Drop the valve head about 1.6 mm (0.064 in.) off the valve seat.

• Use light pressure when moving the valve stem from side to side to obtain clearance reading.

MCF-1082 (J 9666) MCF-1067 (J 8001)

-46-

Cylinder Head and Valves

Valve Guide Reaming/Valve and Seat Grinding

Valve Stem Oil Seal and Valve Spring Installation

1. Ream the valve guides for oversize valves if the clearance exceeds the specifications.

2. Ream the valve guide bores for the oversize valves as necessary.

3. Reconditioning the valve seats is very important.

Recondition valve seat after reaming the valve guide bores or installing the new valve guides.

• 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 its seat in the cylinder head is necessary to ensure that the heat in the valve head is properly carried away.

• Regardless of what type of equipment is used, it is essential the valve guide bores are free from carbon or dirt to ensure the proper centering of the pilot in the guide. The valve seats should be concentric to within 0.79 mm (0.031 in.) total indicator reading.

• Reface pitted valves on a valve refacing machine to ensure the correct relationship between the head and the stem. Replace the valve if the stem is warped, or if the stem shows signs of excessive wear. Replace the valve if the edge of the 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. Use the manufacturer recommendations of equipment to attain the proper results

Tools Required • J 23590 Spark Plug Adapter • MCF-1089 (J 5892-D) Valve Spring Compressor • MCF-1090 (J 38606) Valve Spring Compressor 1. Install the new valve seal (3) over the valve stem and set it against the head.

2. Install the cap (2), rotator, and spring (4).

3. Use the MCF-1089 (J 5892-D).

MCF-1089 (J 5892-D)

4. Use the MCF-1090 (J 38606) if clearance does not permit use of MCF-1089 (J 5892-D).

MCF-1090 (J 38606)

-47-

Cylinder Head and Valves

Valve Lifter Installation

5. Install the valve keys (1). Use grease to hold the valve keys in place.

1. Install the valve lifters.

2. Install the retainer.

6. Carefully release the valve spring pressure, making sure the valve keys stay in place.

7. Remove the J 23590, MCF-1089 (J 5892-D) or MCF-1090 (J 38606).

8. Install the spark plugs.

Valve Rocker Arm and Push Rod Installation 1. Install the pushrod, rocker arm with ball and nut.

Refer to Valve Rocker Arm and Push Rod Removal.

2. Replace 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).

9. Install the valve rocker arms.

10. Install the valve rocker arm cover.

-48-

Cylinder Head and Valves

Cylinder Head Installation

4.

5.

6.

7.

8.

9.

10.

11.

Install the pushrods.

Install the valve rocker arm cover.

Install the oil level indicator tube.

Install the starter relay.

Install the crankcase vent tube.

Connect the spark plug wires to the spark plugs.

Connect the negative battery cable.

Install the following components to the left cylinder head.

• The electrical connector at the coolant temperature sensor 12. Install the alternator and bracket to the right cylinder head.

13. Install the exhaust manifold.

14. Install the intake manifold.

1. Install the cylinder head.

2. Torque the cylinder head bolts in sequence on the first pass.

Tightening torque 3.05 Kgf•m (22lbf•ft) [30 N•m] for cylinder head bolts 3. Use MCF-1074 (J 36660)Electronic Torque Angle Meter, in order to tighten the cylinder head bolts in sequence on the final pass.

Tighten on 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.

-49-

Cylinder Head and Valves

Valve Rocker Arm Cover Left Installation 1. Install the valve rocker arm cover.

2.

3.

4.

5.

Install PCV valve and tube.

Connect the spark plug wires to the spark plugs.

Install the ignition coil.

Connect the negative battery cable.

-50-

Engine Lubrication

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.

-51-

Oil Pan, Pump and Filter Removal and Installation

Removal steps 1. Plug 2. Pan 3. Gasket 4. Bolt 5. Pump 6. Retainer 7. Shaft 8. Pin 9. Pin 10. Cover 11. Screen 12. Plug 13. Valve 14. Spring 15. Filter 16. Fitting 17. Valve 18. Adapter, Oil Filter 19. Gasket 20. Connector, Cooler 21. Gasket

-52-

Oil Pan, Pump and Filter

N O T E

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.

Important: Discard old oil pan gasket.

8. Remove the oil pan.

3. Drain the engine oil.

4. Remove the following fasteners from the oil pan: • The bolts • The nuts

-53-

Oil Pan, Pump, and Filter

Oil Pump Removal

Oil Filter Adapter Removal

1. Remove the oil pan.

2. Remove the bolt that attaches the oil pump to the rear crankshaft bearing cap.

1. Remove the oil filter adapter bolts.

2. Remove the oil filter adapter, oil seal and gasket.

3. Remove the oil pump driveshaft and the retainer.

-54-

Oil Pan, Pump and Filter

3. Remove the seal.

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.

3. Remove the cover bolts.

Oil Pump Disassembly 1. Remove the shaft and retainer.

4. Remove the pump cover.

-55-

Oil Pan, Pump, and Filter

5. Remove the drive gear and the driven gear.

6. Remove the following items.

• The retaining pin • The pressure regulator spring • The pressure regulator valve

Matchmark the gear teeth for assembly.

-56-

Oil Pan, Pump and Filter

N O T E

Oil Pump Assembly

2. Coat the drive gear, the driven gear and the housing gear surfaces with clean engine oil.

3. Install the drive gear and the driven gear into the pump body. Align the matchmarks on the gears.

Install the smooth side of the gear toward the pump cover.

Tools Required • MCF-1071 (J 21882) Oil Pump Screen Installer

Important: Replace the pressure relief valve spring when you reuse the oil pump.

1. Install the following items: • The pressure regulator valve • The pressure regulator spring • The retaining pin

4. Install the pump cover.

-57-

Oil Pan, Pump, and Filter

5. Install the cover bolts.

Tightening torque for cover bolts

1.22 Kgf•m (106 lbf•in) [12 N•m]

6. Inspect the pump for smoothness of operation by turning the oil pump driveshaft by hand.

7. Install the oil pump screen.

• 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 MCF-1071 (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.

MCF-1071 (J 21882)

8. Install the shaft and the retainer.

-58-

Oil Pan, Pump and Filter

Oil Filter Adapter Installation

Oil Pump Installation

1. Install the oil filter adapter.

2. Install the oil cooler lines.

1. Install the oil pump to the engine.

2. Install the oil pan.

3. Install the oil level indicator.

-59-

N O T E

Oil Pan, Pump, and Filter

Installation Procedure

Oil Pan Installation 1. Install the oil pan.

2. Install the engine.

3. Fill the crankcase with oil.

Important: Any time the transmission and the oil pan are off of the engine at the same time, the transmission must be installed before the oil pan. This will allow for the proper measurement of the oil pan tolerance.

1. Install the oil pan and tighten in sequence.

Tightening torque for oil pan bolts and nuts 2.49 Kgf•m (18 lbf•ft) [25 N•m]

2. Use a feeler gauge to check the clearance between the three oil pan-to-transmission contact points. If the clearance exceeds 0.0254 mm (0.010 in.) at any of the three points, repeat the installation steps until the clearance is within specifications.

0.3mm (0.010")

-60-

Front Cover, Timing Chain, and Crankshaft Balancer Removal and Installation

8 7 3 4

6

9 5 2

Removal steps

1

1. Cover 2. Seal 3. Bolt 4. Sprocket 5. Chain 6. Drive Gear 7. Bolt 8. Gear 9. Sprocket

-61-

Front Cover, Timing Chain and Crankshaft Balancer

N O T E

Engine Front Cover Removal

Timing Chain and Sprockets Removal

1. Remove the crankshaft balancer.

2. Remove the water pump.

3.. Remove the engine front cover.

Tools Required • MCF-1086 (J 23523-F) Crankshaft Balancer Remover and Installer • MCF-1066 (J 5825-A) Crankshaft Sprocket Puller

N O T E

Do not reuse the front engine cover. Always install a new front engine cover.

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.

2.

3.

4.

Engine Front Cover Oil Seal Removal 1. Disconnect the negative battery cable.

2. Remove the crankshaft balancer.

3. Remove the crankshaft front seal.

-62-

Remove Remove Remove Remove

the the the the

engine front cover. camshaft sprocket bolts. camshaft sprocket. timing chain.

Front Cover, Timing Chain and Crankshaft Balancer

Crankshaft Balancer Installation

5. Remove the crankshaft sprocket.

6. If necessary, remove the crankshaft sprocket key.

Tools Required • MCF-1086 (J 23523-F) Crankshaft Balancer Remover and Installer 1. Install the crankshaft balancer.

2. Install the accessory drive pulley.

3. Install the accessory drive belt.

4. Install Hydraulic Pump drive shaft.

MCF-1066 (J 5825 A)

Timing Chain and Sprockets Installation Tools Required • MCF-1065 (J 5590) Crankshaft Sprocket Installer 1. Install the key into the crankshaft keyway.

2. Use the MCF-1065 (J 5590) to install the crankshaft sprocket.

3. Install the camshaft sprocket and timing chain. The

Crankshaft Balancer Removal Tools Required • MCF-1086 (J 23523-F) Crankshaft Balancer Remover and Installer 1. Disconnect the negative battery cable.

2. Remove the accessory drive belt.

3. Remove Hydraulic Pump drive shaft.

4. Remove the accessory drive pulley.

5. Remove the crankshaft balancer.

MCF-1086 (J 23523-F)

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Front Cover, Timing Chain and Crankshaft Balancer

Engine Front Cover Oil Seal Installation

gears must mesh to prevent damage to the camshaft retainer.

4. Align timing marks on camshaft gear and

Tools Required • MCF-1085 (J 35468) Crankshaft Seal Installer and Centering Tool 1. Install the crankshaft front seal.

2. Install the crankshaft balancer.

Engine Front Cover Installation 1. Install the front cover.

2. Install the water pump.

3. Install the crankshaft balancer.

crankshaft gear.

5. Install timing chain and camshaft sprocket.

6. Install camshaft sprocket bolts. Be sure to align the camshaft and the crankshaft sprocket alignment marks.

Tightening torque for camshaft sprocket 2.49 Kgf•m (18 lbf•ft) [25 N•m] bolts

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Balancer and Camshaft Removal and Installation

Removal steps 1. Rod 2. Guide 3. Lifter 4. Camshaft Gear 5. Gear Kit 6. Retainer 7. Retainer 8. Camshaft 9. Balancer 10. Bearing Kit - Camshaft 11. Bearing 12. Bearing 13. Plug

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Balancer and Camshaft

Balance Shaft Removal

5. Remove the balance shaft drive gear. Inspect the sprockets for chipped teeth and wear. Worn sprockets will wear a new chain.

Tools Required • MCF-1086 (J 23523-F) Crankshaft Balancer Remover and Installer • MCF-1076 (J 38834) Balancer Shaft Bearing Service Kit 1. Remove the radiator.

N O T E

Check 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.).

2. Remove the valve lifter retainer.

3. Remove the camshaft sprocket bolts.

4. Remove the camshaft sprocket.

6. Remove the bolt and the balance shaft driven gear.

Inspect the balance shaft drive and driven gears for nicks and burrs.

7. Remove the bolt and the balance shaft retainer.

N O T E

Important: The balance shaft drive and driven gears are serviced as a set. The set includes the balance shaft driven gear bolt.

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N O T E

Balancer and Camshaft

Camshaft Removal Tool Required • MCF-1086 (J23523-F) Crankshaft Balancer Remover/Installer 1. Remove the camshaft retainer bolts and retainer.

Important: The balance shaft and the front bearing are serviced only as a package. Do not remove the front bearing from the balance shaft.

8. Use a soft-faced hammer to remove the balance shaft and the front bearing.

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.

9. Use the MCF-1076 (J 38834) to remove the balance shaft rear bearing.

MCF-1076 (J 38834)

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Balancer and Camshaft

Camshaft Bearing Removal

Camshaft and Bearings Clean and Inspect

Tools Required • MCF-1093 (J 33049) Camshaft Bearing Replacer 1. Use the MCF-1093 (J 33049) to remove the inner camshaft bearing.

2. Inspect the camshaft bearings for scratches, pits or a loose bearing fit in the bores. Replace the camshaft bearings if necessary.

3. Remove the rear camshaft plug.

4. Disassemble all the camshaft bearings. Use MCF1093 (J 33049). a. Insert the tool with the correct collet into the camshaft bearing being replaced. b. Turn the tool until the collet has tightened in the bearing. c. Push the center cone against the block and into the first bearing bore to center the tool. d. Drive the bearing from the block. Repeat this procedure to remove the remaining inner camshaft bearings. e. Remove the rear bearing from the front of the block. f. Remove the front bearing from the rear.

5. Clean the camshaft bearing bores in the block.

Tools Required • MCF-1091 (J 7872) Magnetic Base Indicator Set 1. Measure the camshaft journals with a micrometer.

If journals are more than 0.025 mm (0.0010 in.) outof-round, replace the camshaft.

2. Measure camshaft runout. a. Mount the camshaft in V-blocks or between centers. b. Check the intermediate camshaft journal for runout. c. If runout exceeds 0.065 mm (0.0026 in.), camshaft is excessively bent and should be replaced.

MCF-1091 (J 7872)

MCF-1093 (J 33049)

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Balancer and Camshaft

Camshaft Bearing Installation

c. Place the new bearing on the bearing tool. Hold the bearing tool and bearing against the bearing bore. Align the bearing hole in the block. d. Thread the puller screw into the bearing tool enough to hold the tool and the bearing in place. e. Holding the puller screw with a wrench, turn the nut with a second wrench to pull the camshaft bearing into place. f. Remove the puller screw, the pilot, and the bearing tool.

7. Install a new camshaft rear bearing hole plug. Coat the outside diameter of the plug with (MCF P/N 12346004) (GM P/N 2I4256) sealant or equivalent. a. Install the plug flush to 0.80 mm (1/32 in.) b. Install the plug while RTV is still wet.

Tools Required • MCF-1093 (J 33049) Camshaft Bearing Removal/Installer 1. Use the MCF-1093 (J 33049) to install the front and rear camshaft bearings.

2. Install the outer camshaft bearings first. These bearings serve as guides for the pilot, and these bearings help center the inner bearings during installation.

3. Fit the correct cam bearing into the bore. The cam bearing bores vary in size.

4. Assemble the outer camshaft bearings. Drive the bearings into place using MCF-1093 (J 33049).

N O T E

Camshaft Installation Tool Required • MCF-1086 (J 23523-F) Crankshaft Balancer Remover/Installer 1. Install the camshaft.

2. Install the timing chain and sprocket.

3. Install the valve lifters.

4. Install the radiator.

Important: The camshaft bearing hole (holes) must align with the oil hole (or holes) in the block. On some engines the oil holes may be difficult to see. If these oil holes are difficult to see use a piece of 2 mm (3/32 in.) rod to check the alignment. Rod length should be 762 mm (30 in.).

MCF-1093 (J 33049)

5. Inspect the alignment of the camshaft bearing hole to the oil hole (or holes) in the block.

6. Assemble the inner camshaft bearing. Use MCF1093 (J 33049). a. Assemble the tool with the pilot engaged in the front bearing and the pilot flange against the front face of the block. b. Slide the puller screw (with the nut and the washer) through the pilot.

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Balancer and Camshaft

Balance Shaft and Bearing Clean and Inspect 1. Inspect balance shaft front roller bearing and rear sleeve bearing for damage or excessive wear. The bearings are serviced as an assembly. Use the proper tools for properly servicing the bearings.

2. Inspect balance shaft drive and driven gears for nicks or burrs. Replace gears that are damaged.

3. Inspect front and rear bearing journal diameters.

Replace the balance shaft if the diameter exceeds specifications.

Balance Shaft Installation Tools Required • MCF-1086 (J 23523-F) Crankshaft Balancer Remover and Installer • MCF-1076 (J 38834) Balance Shaft Bearing Service Kit • MCF-1075 (J 36996) Balance Shaft Installer • MCF-1070 (J 8092) Universal Driver Handle • MCF-1074 (J 36660) Torque/Angle Meter 1. Install the balance shaft and gears.

2. Install the valve lifter retainer.

3. Install the timing chain and the camshaft sprocket.

4. Install the radiator.

MCF-1070 (J 8092)

MCF-1075 (J 36996)

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Crankshaft, Flywheel, Rear Seal, and Bearings Removal and Installation

2

4 6

1

3 5 13 12 9 7

11 10 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

8

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Crankshaft, Flywheel, Rear Seal, and Bearings

Engine Flywheel Removal

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.

1. Remove the transmission.

2. Remove the flywheel.

Crankshaft Rear Oil Seal and Housing Removal

Crankshaft, Bearings and Bearing Cap Removal

1. Remove the crankshaft rear oil seal housing nuts and bolts.

2. Remove the crankshaft rear oil seal housing, seal, and gasket.

1.

2.

3.

4.

Remove the crankshaft bearing cap bolts.

Remove the crankshaft bearing caps.

Remove the crankshaft.

Remove the crankshaft bearings from the bearing caps and from the engine block.

5. Clean and inspect upper and lower bearings for damage and wear.

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Crankshaft, Flywheel, Rear Seal, and Bearings

Service Prior to Assembly 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.

10. Use a dial indicator or feeler gauge to measure end play between the front of the rear of the crankshaft bearing cap and the crankshaft thrust surface. If a feeler gauge is used, measure between the thrust surface of the crankshaft bearing and the crankshaft. Refer to General Specifications for clearance

Crankshaft, Bearings and Bearing Cap Installation

a

1. Install the crankshaft bearing into the engine block and the crankshaft bearing caps.

2. Coat the crankshaft bearings with clean engine oil.

3. Install the crankshaft.

4. Install the crankshaft bearing caps with crankshaft bearings.

5. Be sure the cap directional arrows point toward the front of the engine block and the cap is in its original position.

6. Install the crankshaft bearing cap bolts and studs.

7. Thrust the crankshaft rearward to set and align the thrust bearings and the bearing caps.

8. Thrust the crankshaft forward to align the rear faces of the rear crankshaft bearing.

9. Tighten the crankshaft bearing cap bolts

b

c

d

N O T E

Tightening torque 1st pass for crankshaft bearing 2.08 Kgf•m (15 lbf•ft) [20 N•m] cap bolts 2nd pass 10.66 Kgf•m (77 lbf•ft) [105 N•m]

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 Engine Mechanical Specifications.

If the correct end play cannot be obtained, verify that the correct size crankshaft bearing has been installed.

Refer to Engine Mechanical 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 crankshaft bearing cap at a time, until the tight crankshaft bearing is located.

Burrs on the the crankshaft bearing cap, foreign matter between the crankshaft bearing and the engine block or the crankshaft bearing cap, or a faulty crankshaft bearing could cause a lack of clearance at the crankshaft bearing.

Bearing Clearance Measuring Procedures The crankshaft bearings are of the precision insert type and do not use shims for adjustment. If the clearances are excessive, then new upper and lower 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-ha;f of a standard crankshaft bearing with one-half of a undersize crankshaft bearing.

In order to determine the correct replacement 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.

Important: In order to properly measure the crankshaft end play, the crankshaft, the crankshaft bearings, the crankshaft bearing caps,. and the crankshaft bearing cap bolts must be installed into the engine block and the bolts tightened to specifications.

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Crankshaft, Flywheel, Rear Seal, and Bearings

2. Install the rear oil seal housing nuts and bolts. a. Tighten the crankshaft rear oil seal housing.

Tightening torque for rear oil seal housing 1.52 Kgf•m (11 lbf•ft) [15 N•m] nuts and bolts

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 Engine Mechanical Specifications

3. Coat the new oil seal entirely with clean engine oil.

4. Install the seal onto the MCF-1073 (J 35621).

5. Install the MCF-1073 (J 35621) onto the rear of the crankshaft. Tighten the screws snugly to ensure the seal is installed squarely over the crankshaft.

6. Install the crankshaft rear oil seal to the crankshaft and the crankshaft rear oil seal housing. Tighten the wing nut on the MCF-1073 (J 35621) until the oil seal bottoms.

7. Remove the MCF-1073 (J 35621) from the crankshaft rear oil seal housing.

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 flywheel 10.25 Kgf•m (74 lbf•ft) [100 N•m] bolts 4. Install the transmission.

Crankshaft Rear Oil Seal and Housing Installation

N O T E

Tools Required • MCF-1073 (J 35621) Crankshaft Rear Oil Seal Installer Important: Always use a new crankshaft rear oil seal

and new crankshaft rear oil seal housing gasket when you install the crankshaft rear oil seal housing.

1. Install the new gasket and the crankshaft rear oil housing on to the studs.

MCF-1073 (J 35621-B)

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Cylinder Block Cleaning and Inspection

T= 4.3-6.0 kgf•m (31.1-43.4 lbf•ft) [42-59 N•m]

Disassembly steps T=4.3-6.0 kgf•m (31.1-43.4 lbf•ft) [42-59 N•m]

1. Engine support (R.H.) 2. Engine support (L.H.) 3. Cylinder block

7EN0035

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Cylinder Block

Cylinder Block Cleaning

5. Check and inspect the cylinder walls for scratches and signs of seizure. If necessary, rebore the cylinders to oversize or replace the cylinder block.

6. Measure cylinder bores following areas: • Diameter • Out-of-round • Taper • Excessive ring ridge 7. If excessive wear is found, rebore the cylinders to oversize and replace the pistons and piston rings.

Checking should be made at the positions shown in the figure.

1. Remove the front oil gallery plugs.

2. Remove the rear oil gallery plugs.

3. Disconnect the pump oil pressure switch and fitting.

4. Clean the following areas: • The engine block in solvent • The gasket surfaces • The coolant passages • The oil passages

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A U T IO N !C Cylinder Block

Cylinder Block Inspection 1. All expansion plugs for lack of fit or leakage.

2. Valve lifter bores for deep scratches and deposits.

3. Cracks in the block.

• Cylinder walls • Coolant jackets • Engine mount bosses • Main bearing webs 4. Main bearing bores and caps.

• All main bearing bores should be rounded and uniform in ID at all of the bearing supports.

• The area where the main bearing inserts contact the main bearing bore should be smooth.

• If a main bearing cap is found to be damaged, replace the cap and line-bore the block.

5. Cylinder head mounting surface for flatness, using a precision straight edge and feeler gage. a. Set the straight edge on the sealing surface to be inspected. b. Take the feeler gage at various locations, check the gap between the straight edge and the sealing surface. c. 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. d. 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.

6. Oil pan, timing cover, and intake manifold mounting surfaces for nicks. Minor irregularites may be cleaned up with a flat file.

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.

Standard value: 0.05 mm (0.002 in.) Limit: 0.1 mm (0.004 in.) Grinding limit value: 0.2 mm (0.008 in.)

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Cylinder Block

A U T IO N !C

N O T E

Reboring the Cylinders

Reboring should be made in the order of the cylinders numbers to prevent warping due to excessive temperature.

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.

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.

7. Perform the following procedure to bore and hone the cylinders. Use proper boring equipment, as recommended by the manufacturer. a. Draw a flat file across the top of the cylinder head block several times to remove any burrs or gasket materials. If the cylinder head block is not completely smooth and flat, tilt the boring bar to produce an incorrect angle of the cylinder to the crankshaft. b. Finish the honing operation with a 45-65 degree cross-hatch pattern on the cylinder walls. The finish marks should be clean but not sharp, free from imbedded particles and torn or faded metal.

8. Reinstall the pistons: a. Measure the piston 11.5 mm (0.45 in.) from the bottom of the piston skirt and at right angles to the piston pin to install the piston correctly. b. Bore the cylinder to the same diameter as the piston. c. Hone the cylinder to provide the specified clearance. Use proper boring equipment, as recommended by the manufacturer. d. Check each cylinder for proper cylinder-to-piston clearance.

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.

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.

Standard value: 0.02-0.04 mm (8x10-4-1.6x10-3 in.)

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Cylinder Block

A U T IO N !C

Cylinder Block Plug Installation

Installation Procedure Tools Required • J 41712 Oil Pressure Switch Socket

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.

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.

4. Install the spring type S pin (crankshaft rear oil seal housing locator) (if required).

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Cylinder Block

5. 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).

6. Install the new expansion cup plug (balance shaft rear bearing hole).

9. 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.

10. Install 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.

Tighten the engine block left side oil gallery plug Tightening torque for left and right rear oil gallery plug

Left 2.08 Kgf•m (15 lbf•ft) [20 N•m] Right 3.05 Kgf•m (22 lbf•ft) [30 N•m]

N O T E

7. 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).

8. Install the new expansion cup plug (camshaft rear bearing hole).

and the engine block right rear oil gallery plug 11. Install the dowel straight pins (transmission locator) (if required).

-80-

Cylinder Block

12. Install the left side dowel pins (cylinder head locator) (if required).

14. Apply sealant MCF P/N 2I4256/GM P/N 12346004 or equivalent to the threads of the engine block coolant drain hole plug.

15. Install the engne block coolant drain hole plug.

Tightening torque engine block coolant drain hole plug

13. Install the right side dowel pins (cylinder head locator) (if required).

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2.08 Kgf•m (15 lbf•ft) [20 N•m]

Cylinder Block

N O T E N O T E

22. Install the knock sensor.

16. Apply sealant MCF P/N 2I4256/GM P/N 12346004 or equivalent to the threads of the engine oil pressure sensor fitting.

Tightening torque for knock sensor

Important: Do not loosen the engine oil pressure fitting after the initial torque has been obtained.

Tightening torque for engine oil pressure sensor fitting

1.52 Kgf•m (11 lbf•ft) [15 N•m]

17. Install the engine oil pressure sensor fitting.

18.

19.

20.

21.

Important: Do not rotate the engine oil pressure fitting clockwise more than 359 degrees after the initial torque has been obtained.

Rotate the engine oil pressure sensor fitting clockwise to the proper position Apply sealant MCF P/N 2I4256/GM P/N 12346004 or equivalent to the threads of the engine oil pressure gauge sensor.

Install the engine oil pressure gauge sensor using the J 41712.

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]

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2.08 Kgf•m (15 lbf•ft) [20 N•m]

Piston and Connecting Rod Removal and Installation

9 T=4.3-6.0 kgf-m (31.1-43.4 lbf-ft) [42-59 N•m]

8

5 6

7

4

Removal steps 1. Nut 2. Rod Cap 3. Bearing 4. Bearing 5. Piston and Connecting Rod Assy 6. Pin 7. Rod - Connecting 8. Piston 9. Ring Kit

3

2 1

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Piston and Connecting Rod

Piston, Connecting Rod, and Bearing Removal

5. Use the MCF-1064 (J 5239) to remove the connecting rod and the piston out of the top of the engine block.

Tools Required • MCF-1064 (J 5239) Guide Set 1. Remove the 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.

2. Remove the connecting rod nuts.

3. Remove the connecting rod cap.

MCF-1064 (J 5239)

N O T E

Important: Place matchmarks or numbers on the connecting rods and the connecting rod caps.

Assemble the connecting rod caps to the matching connecting rods.

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.

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Piston and Connecting Rod

N O T E

Piston and Connecting Rod Disassembly

Piston and Connecting Rod Clean and Inspect

Tools Required • MCF-1083 (J 24086-C) Piston Pin Removal Set

1. Clean the connecting rod in cleaning solvent.

2. Dry the connecting rod with compressed air.

3. Clean the varnish from the piston skirts and the pins with the cleaning solvent.

4. Clean the piston ring grooves with a groove cleaner.

5. Do not use a wire brush to clean any part of the piston.

6. Clean the piston oil ring holes and the slots.

7. Inspect the connecting rod for twisting, nicks, and cracks. Replace any damaged connecting rods.

8. Inspect the pistons for the following conditions.

• Cracked ring lands, skirts, or pin-bosses.

• Nicks or burrs in the grooves that may cause binding.

Important: Mark the piston for installation to the proper cylinder.

1. Remove the piston rings from the pistons.

2. Remove the pin from the piston.

MCF-1083 (J 24086-C)

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Piston and Connecting Rod

Piston Selection

Piston, Connecting Rod and Bearing Installation

1. Measure the piston-to-cylinder bore clearance to determine the suitability of a used piston.

2. Measure the piston-to-cylinder bore clearance as follows. a. Use a boring gauge to measure the cylinder bore diameter at a point of 66 mm (2.5 in.) from the top of the cylinder bore. b. Use a micrometer or caliper to measure the piston 11.5 mm (0.45 in.) from the bottom of the skirt at right angles to the piston pin. c. Subtract the piston diameter from the cylinder bore diameter to indicate piston-to-bore clearance. d. Compare the measurements to specifications. e. Mark the piston for installation to the proper cylinder. f. A used piston may be installed, if clearances are within specifications.

Tools Required • MCF-1064 (J 5239) Guide Set • MCF-1068 (J 8037) Piston Ring Compressor • MCF-1074 (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 piston with the stamped arrow facing forward.

3. Install the piston assembly into its matched bore.

When assembled, the flanges on the connecting rod and cap should face the front in the left bank and the rear in the right bank.

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Piston and Connecting Rod

4. Use the MCF-1068 (J 8037) and the MCF-1064 (J 5239) to lightly tap the top of the piston with a wooden hammer handle. a. Hold the MCF-1068 (J 8037) firmly against the engine block until all of the piston rings enter the cylinder bore.

6. Install the connecting rod cap and nuts.

Tightening torque for rod cap nuts N•m]

1st pass 2.77 Kgf•m (20 lbf•ft) [27

• On the final pass, use the MCF-1074 (J 36660) to tighten the nuts an additional 70 degrees.

7. When all of the connecting rod bearings are installed, tap each connecting rod assembly lightly parallel to the crankpin to make sure they have clearance.

MCF-1068 (J 8037)

b. Use the MCF-1064 (J 5239) to guide the connecting rod onto the crankshaft journal.

5. Remove the MCF-1064 (J 5239).

MCF-1064 (J 5239)

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Piston and Connecting Rod

N O T E N O T E

8. Use a feeler gauge or a dial indicator to measure the side clearance between the connecting rod caps. The rod side clearance should be 0.160.43 mm (0.006-0.017 in.).

2. Install the piston rings onto the piston. The marked side of the piston rings must face the top of the piston.

3. Use the following procedure to locate the piston ring gaps. a. Install the oil ring spacer in the groove. b. Hold the spacer ends together and properly locate the gap to install the lower oil ring rail. c. Properly locate the gap and install the upper oil ring rail. d. Flex the oil ring assembly to make sure the rings are free. e. Install the lower compression ring. f. Install the upper compression ring.

4. Install the compression piston rings with the ring gaps 120 degrees apart. Stagger the end gaps on the oil control rings.

Piston and Connecting Rod Assembly

Important: After the MCF-1083 (J 24086-C) installer hub bottoms on the support assembly, do not exceed 35,000 kPa (5000 psi) or the tool may be damaged.

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 flange on the connecting rod must face the front of the piston on the left hand assembly and face the rear of the piston on the right hand assembly.

1. Install the piston pin and connecting rod assembly. a. Lubricate the piston holes in both the piston and the connecting rod assembly. b. Press the piston pin into the piston and connecting rod assembly using the MCF-1083 (J 24086-C).

MCF-1083 (J 24086-C)

c. Inspect the piston on the piston pin for freedom of movement.

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Carburetor, Gasoline Removal and Installation

3

4 1 2

T=2.8 kgf•m (20 lb•ft) [28 N•m]

5 6 T=2.5 kgf•m (18 lb•ft) [25 N•m]

7 8 1. Carburetor 2. Fuel Inlet 3. Intake Air Connector 4. Accelerator Cable 5. Carburetor Connector 6. Gasket 7. Adapter 8. Gasket

-89-

Carburetor, Gasoline

Removal Procedure 1. Remove Intake Air Connector 2. Disconnect Accelerator Cable from Carburetor 3. Disconnect Carburetor Connector Hint: Before disconnecting the emission control hoses, use tag to identify how they should be reconnected.

4. Disconnect the Following Hoses: • Fuel inlet hose • Emmision control hoses • Vacuum Laines 5. Remove the four carburetor mounting nuts.

6. Lift out the carburetor.

7. Cover the inlet hole of the intake manifold with a cloth.

-90-

Carburetor Assembly

Carburetor Assembly (Upper) Removal and Installation

Disassembly steps 1. Stud bolt 2. Nipple union 3. Pivot bolt 4. Acceleration pump arm 5. FICB link 6. Air Horn 7. Wire clamp 8. Pivot pin 9. Wire 10. Float 11. Plunger 12. Spring 13. Needle valve 14. Acceleration pump plunger 15. Plunger boot 16. Air horn gasket 17. Needle valve seat 18. Gasket 19. Screw 20. Retainer 21. Power piston 22. Spring 23. Primary upper slow jet

24. Screw 25. Coil housing 26. Gasket 27. Screw 28. Cover 29. Spring 30. E-ring 31. Stopper 32. Spring 33. Collar 34. Diaphragm 35. Solenoid Valve 36. Gasket 37. Screw 38. Choke lever 39. Screw 40. Thermostat housing

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Carburetor Assembly

Carburetor Assembly (Lower) Removal and Installation

Disassembly steps 1. Discharge weight 2. Spring 3. Check ball 4. Plunger spring 5. Retainer 6. Check ball 7. Primary slow jet 8. Plug 9. Spring 10. Ball 11. Plug 12. Ball 13. Power valve 14. Passage plugs 15. Gaskets 16. Primary main jet 17. Gasket 18. Passage ring 19. Screw 20. Primary small venturi 21. Gasket 22. Snap ring 23. Screw 24. Fast idle cam breaker (FICB) 25. Fast idle cam 26. Passage screw 27. Bolt 28. Carburetor Body 29. Carburetor flange 30. Insulator

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Carburetor Assembly

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.

3. Use SST carburetor driver set.

Air Horn Disassembly

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.

1. Remove Carburetor Stud Bolt and Nipple Union

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.

5. Remove Float and Needle Valve Remove the float pivot pin, float and needle valve subassembly

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Carburetor Assembly

6. Remove Acceleration Pump Plunger a. Remove the pump plunger and boot. b. Remove air horn gasket.

9. Remove Primary Upper Slow Jet

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.

7. Remove Needle Valve Seat a. Remove the needle valve seat and gasket.

8. Remove Power Piston a. Remove the screw, retainer, power piston and spring.

12. Remove Choke Breaker (CB) a. Remove the three screws, cover and spring.

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Carburetor Assembly

b. Remove the E-ring, stopper, spring collar and diaphragm

15. Remove Fast Idle Cam Breaker (FICB) Link a. Remove the screw and FICB link.

Carburetor Body Disassembly

13. Remove Fuel Cut Solenoid Valve a. Remove the solenoid valve and gasket.

1. Remove Check Balls for Acceleration Pump a. Remove the pump discharge weight, spring and large ball. b. Remove the plunger spring.

14. Remove Thermostat Housing a. Remove the screw and choke lever. c. Using tweezers, remove the ball retainer. d. Remove the small ball.

b. Remove the two screws and thermostat housing.

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Carburetor Assembly

2. Remove Slow Jets a. Remove the primary slow jet.

b. Remove the primary main jets and gaskets.

6. Remove Small Venturies a. Remove the passage ring.

3. Remove Check Balls for Auxiliary Acceleration Pump (AAP) a. Remove the plug, spring and ball (a). b. Remove the plug and ball (b).

b. Remove the two screws, primary small venturi and gasket.

4. Remove Power Valve

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

5. Remove Primary Main Jets a. Remove the two passage plugs and gaskets.

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Carburetor Assembly

General Cleaning Procedure

8. Remove Fast Idle Cam

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.

9. Separate Carburetor Body and Flange a. Remove the passage screw and spring washer.

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.

b. Remove the two bolts. c. Separate the body and flange. d. Remove the insulator.

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Carburetor Assembly

2. Inspect Power Piston a. Check that the power piston moves smoothly.

5. Inspect Choke Heater (Coil Housing) a. Using an ohmmeter, measure the resistance between the terminals.

Resistance (Cold): 17.3 - 18.7 at 20°C (68°F) If a problem is found, replace the choke heater.

3. Inspect Power Valve a. Check for faulty opening and closing action.

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.

4. Inspect Fuel Cut 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.

c. Install the passage screw together with the spring washer.

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Carburetor Assembly

2. Install Fast Idle Cam

b. Install the passage ring.

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.

5. Install Primary Main Jets a. Install the primary main jets with new gaskets.

b. Install the primary passage plugs with new gaskets.

4. Install Small Venturies a. Install a new gasket and the primary venturi with the two screws.

6. Install Power Valve

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Carburetor Assembly

Air Horn Assembly

7. Install Primary Slow Jet

1. Install Fast Idle Cam Breaker (FICB) Link.

Install the FICB link with the screw.

8. Install Check Balls for Acceleration a. Install the plunger small ball. b. Using tweezers, install the ball retainer.

2. Install Thermostat Housing a. Install the thermostat housing with the two screws.

c. Install the plunger spring (c). d. Install the pump discharge large ball, spring and weight (d).

b. Install the chock lever with the screw.

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Carburetor Assembly

3. Install Fuel Cut Solenoid Valve a. Install a new O-ring to the solenoid valve. b. Install the solenoid valve together with a new gasket.

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.

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.

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.

c. Install the following parts with the three screws: • Spring • Cover

b. Pull on the wire to check that it is securely locked.

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Carburetor Assembly

7. Install Primary Upper Slow Jet

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.

8. Install Power Piston a. Install the spring and power piston with the retainer and screw. b. Install the float with the pivot pin.

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.

Using SST, measure the clearance between the float tip and air horn. SST 09240-00014 Float level (Raised position): 7.0 mm (0.276 in.)

Hint: This measurement should be made without a gasket on the air horn.

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Carburetor Assembly

d. Adjust by bending the portion of the float lip marked A.

e. Lift up the float. Using SST, measure the clearance between the needle valve plunger and float tip. SST 09240-00020 Float level (lowered position): 0.9 - 1.1 mm (0.035 - 0.043 in.)

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.

h. Assemble the clip onto the needle valve.

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.

13. Install Needle Valve and Float a. Hook the needle valve clip to the lip portion of the float.

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Carburetor Assembly

b. Install the float and secure it with the pivot pin.

15. Connect Fast Idle Cam Breaker (FICB) Link

14. Install Air Horn Assembly a. Install the wire clamp in position.

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. 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

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Carburetor Assembly

Carburetor Adjustment

b. Depending on vehicle operating conditions, turn the coil housing and adjust the engine starting mixture.

If too rich ........ Turn clockwise If too lean ....... Turn counterclockwise

Hint: Use SST 09240-00014 to make adjustment.

1. Check and Adjust Throttle Valve Opening a. Check the full opening angle of the primary throttle valve.

Standard angle: 90° from horizontal

3. Check and Adjust Fast Idle Setting a. Position the fast idle lever onto the 1st step as shown. b. Adjust by bending the primary throttle stop lever.

b. Check the primary throttle valve angle.

Standard angle: 23.3° - 25.3° from horizontal

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).

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Carburetor Assembly

c. Adjust by turning the fast idle adjusting screw.

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.

4. Check and Adjust Unloader a. With the primary throttle valve fully opened, check the choke valve angle.

Standard angle: 35° - 39° from horizontal

• Check that the fast idle lever is set in the 1st step of the fast idle cam as shown.

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.

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Carburetor Assembly

d. Adjust by bending the FICB lever.

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.

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 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

d. Adjust by turning the CB adjusting screw.

c. Adjust turning the idle speed adjusting screw.

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Carburetor Assembly

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.

b. Place the carburetor on the insulator. c. Install the four carburetor mounting nuts.

N O T E

Tightening torque for carburetor mounting nuts

130 Kgf•m (9 lbf•ft) [13 N•m]

Use care not to screw it in too tightly and damage the screw tip.

2. Connect the Following Hoses a. Emission control hoses b. Fuel inlet hose c. Outer vent control hose d. Vacuum lines Between thermal switch and choke pulloff

10. Check for smooth operation of each part.

11. Install carburetor stud bolt.

Between choke breaker and intake manifold

Operational Adjustments 1.

2.

3.

4.

5.

Start engine Allow engine to reach operating temperature.

Install tachometer.

Idle speed adjustment.

Idle mixture adjustment.

How to Adjust Using 1. Tachometer Adjustment 2. Exhaust Analyzer 3. Vacuum Gauge Adjustments

3.

4.

5.

6.

7.

8.

9.

10.

Carburetor Installation 1. Install Carburetor a. Place the insulator and new gaskets on the intake manifold.

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Connect Carburetor Connector Connect Accelerator Cable Install Intake Air Connector Fill with Coolant Adjust Idle Speed and Idle Mixture Adjust Fast Idle Speed Adjust Dash Pot (DP) Setting Speed Adjust Throttle Positioner (TP) Setting Speed

Electrical Throttle and Governor Control System

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 to any malfunction.

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.

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. Overrun 2. Accelerator sensor fault 3. Idle switch fault 4. Throttle CLOSE position detection switch fault 5. Throttle OPEN position detection switch fault 6. Stepping motor fault 7. Rotary pulse fault 8. Alternator fault The motor output shall perform PWM of approximately 60% to prevent the motor from overheating.

Characteristics Low idle: 750 ± 50 rpm High idle: 2650 rpm Speed regulation (rated load): +/- 2% (at 2650 rpm) Instantaneous maximum speed: 2800 rpm Governor: All-speed type

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Electrical Throttle and Governor Control System

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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Electrical Throttle and Governor Control System

Schematic

-111-

Electrical Throttle and Governor Control System

Method of Operation

Speed Control

Initial Setting Turning the power ON allows the conroller 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 in 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 spped 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 noload 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 is run at the target speed determined on the basis of the “accelerator-target speed characteristic” curve. (This is all-speed characteristic.)

The target of steady-state speed regulation id +/-2% (at 2650 rpm) with the rated load.

Stopping As the starter switch key is turned to OFF position, the controller power source is turned OFF and, 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 once and the position of the throttle CLOSE position detection switch is detected. Since then, the control function is continued on the basis of this switch position.

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Electrical Throttle and Governor Control System

GM 4.3L Engine ECU Diagnostics Tester Tools required • ECU Diagnostics Tester MCF-1101 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 tester MCF-1101 to the OFF position.

4. Turn the truck key switch to the ON position (the light on the tester MCF-1101 will flash continuously at 1 second intervals).

5. Flip the toggle switch on tester MCF-1101 to the 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 OFFand remove the diagnostic tool.

How to clear the error history from the ECU. 1. Repeat Steps 1 and 2 above.

2. Move the toggle switch on tester MCF-1101 to the ON position.

3. Turn the truck key switch to the ON position (the light on tester MCF-1101 will flash continuously at 1 second intervals).

4. Turn the key switch OFF and remove the diagnostic tool.

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Electrical Throttle and Governor Control System

Error Code Flashes

Error

Reason

Result

1

Overspeed of the engine

Then engine ran at over 3000 rpm for more than 0.3 seconds

The throttle shuts down and will not operate until restart.

2

Input signal from the accelerator sensor is out of spec

The voltage of the input signal from the accelerator sensor exceeded limitation.

The Input signal from the accelerator sensor does not increase when the idle switch on the carburetor is off.

The throttle shuts down and prevents the starter motor from activating. Will not operate until restart.

3

The idle position sensing switch on the carburetor is not correct

The idle position sensing switch on the carburetor stays at on when the input signal from accelerator sensor opens more than 1/2.

The maximum speed is limited to 150 rpm.

4

The throttle close sensing switch on the carburetor is not correct

During calibration, the ECU did not receive an on-signal from the throttle close-sensing switch.

See #2 above.

5

The throttle open sensing switch is not correct

During calibration, the ECU did not receive an on-signal from the throttle open-sensing switch.

See #3 above.

6

The stepping motor is not correct

The ECU received a throttle close or open signal from the sensing switch during the normal throttle lever stroke (expect high or low idle).

See #1 above.

7

The revolution signalpulse from the distributor is not correct

No revolution signal pulse from the distributor while the voltage of the “L” terminal of the alternator is in the normal operating range.

See #1 above.

8

Alternator is not correct

The voltage of the “L” terminal of the alternator remains lower than limitation over 30 seconds when a revolution signal pulse exists.

See #1 above.

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Ignition System and Distributor Removal and Installation

Removal steps A A B C

A A B C D

4 1

1. Spark Plug Wires 2. Ignition Coil Wire 3. Coil 4. Distributor 5. Gasket 6. Spark Plugs

2

5

3

6

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Ignition System - Distributor Removal and Installation

1

13

6 2 7

14 15

8

16

9 3 10

11 4 Removal steps 1. Screw 2. Distributor Cap 3. Rotor 4. Shaft Assembly 5. Retainer 6. Shield 7. Sensing Coil 8. Pole, Stationary 9. Screw (4) 10. EST Module 11. Pin 12. Housing 13. Tab Washer 14. Washer 15. Gear 16. Roll Pin

12

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5

C

N O T E A U T IO N !C

Ignition System and Distributor

Distributor Disassembly

Distributor Removal

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.

Position the engine on 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.

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. Then put a corresponding mark on the distributor housing and then 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 then remove the distributor.

A U T IO N !C

3. Remove the gear, washer, and tab washer.

4. Remove the shaft with the pole piece and plate from the housing.

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 module to the plate. Remove the module.

N O T E

Distributor Assembly

34403

A small amount silicon grease is supplied with each replacement module. If silicon grease is needed, use the 5P8937 Heat Sink Compound.

1. Completely cover the bottom of the module with a thin layer of 5P8937 Heat Sink Compound or an equivalent compound for heat transfer.

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A U T IO N !C

Ignition System and Distributor

Make sure the bottom of the module is completely covered with a thin layer of 5P8937 heat sink compound. If the silicon grease is not correctly applied, the module can be damaged by heat.

2. Install the module on the housing using the two screws.

3. Install the sensing coil on the shaft assembly.

Make sure the locking tab is in the correct position.

4. Install the shield on the sensing coil and the new retainer to fasten the shield and coil.

5. Install the shaft assembly into the housing. Install the tab washer, the washer, and the gear on the shaft. Align the marks on the gear and the shaft for correct alignment.

6. Install the roll pin into the gear to lock the gear and shaft together. Rotate the shaft to make sure the teeth on the shaft assembly do not touch the pole piece.

A Spark Plug Wires and Coil Wire Installation 1. Measure each spark plug wire resistance.

2. Measure coil wire resistance.

3. Install the spark plug wires on the distributor cap as shown.

4. Install the wires on spark plugs following the firing order shown. Firing Order 165432

A Spark Plug Wires and Coil Wire Removal 1. Remove all wires by the boots, do not pull on the wires. Note the arrangement of the wires before removing.

2. Check all wires and boot ends for cracks, burnt or

hard rubber. Inspect wires for broken insulation or chafing.

3. Inspect wire ends and boots for tight fit on and over spark plugs and distributor.

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Ignition System and Distributor

B Coil Installation and Testing

5. Install the coil wire on the distributor and then 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.

A U T IO N !C

B Coil Removal

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.

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.

N O T E

Ignition Sensing Coil Test

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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Ignition System and Distributor

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.

C Distributor Installation 1. Use the following steps to install: 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. c. Install a new gasket between distributor housing and the engine. d. Install the distributor in the engine.

Hint: Make sure both the rotor and distributor housing marks are correctly aligned before going to the next step. Also make sure that the distributor is fully inserted in the engine.

2. Install the clamp and the bolt. Tighten the bolt enough to hold the distributor in position, but do not tighten completely.

3. If the distributor cap is not being replaced, inspect the cap for carbon, cracks or small holes. Replace the distributor cap if it is dirty or damaged. Install the distributor cap on the distributor. Install the high voltage wires in their correct positions.

4. Install the coil lead wire and engine harness connector to the distributor.

5. Reconnect the negative battery cable.

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Ignition Timing

N O T E

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. Locate the correct timing mark, Gasoline or LP (0° BTDC Gasoline)[ 8° BTDC L.P.G.] on the balancer pulley and front engine cover.

Ignition System and Distributor

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 MCF-1094 to the 4-pin 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.

A U T IO N !C

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.

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.

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Ignition System and Distributor

D Spark Plug 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. 1.52in, 060mm gap.

7. Do not over tighten spark plugs when replacing or inspecting them. See Torque section for values.

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Alternator and V-Belt Removal and Installation

T= 2.49 Kgf•m (18 lbf•ft) [25 N•m]

T= 4.16Kgf•m(30 lbf•ft) [41 N•m]

Removal Steps

T= 5.94Kgf•m (43 lb•ft) [58 N•m] T= 2.49Kgf•m (18 lb•ft) [25 N•m]

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1. Bolt 2. Bolt 3. Alternator 4. Belt 5. Pulley 6. Pulley

Alternator and V-Belt

Alternator Removal and Installation

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

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Alternator and V-Belt

Accessory Drive Belt Replacement Removal Procedure 1. Loosen alternator mounting bolts.

2. Rotate alternator to reduce belt tension and remove drive belt.

Installation Procedure 1. Route the belts over all the pulleys including the alternator.

2. Rotate alternator to tension belts and tighten mounting bolts.

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Starter Motor Removal and Installation

6

5

4

3

2 1

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Removal Steps 1. Bolt 2. Spring Washer 3. Starter Motor 4. Cord 5. Starter Harness 6. Starter Relay

Starter Motor

Starter Motor Testing

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.

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.

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 disassembled immediately. However, if the armature does rotate freely, the motor should be given a no-load test before disassembly.

Troubleshooting Cranking Circuit Before removing any unit in a cranking circuit for repair, the following checks should be made.

The no-load test may point to specific defects which can be verified with tests when disassembled. The noload test also can be used to indicate normal operation on a repaired motor before installation.

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.

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Starter Motor

No-Load Test

c. Broken brush springs, worn brushes, high insulation between the commutator bars or other causes which would prevent good contact between the brushes and commutator.

5. Low no-load speed and low current draw indicate: a. High internal resistance due to poor connections, defective leads, dirty commutator and causes listed under Number 4.

Disassembly If the motor does not perform in accordance with published specifications, it may need to be disassembled for further testing of the components.

Normally the cranking motor should be disassembled only so far as is necessary to make repairs or replace the defective parts.

1. Detach lead from solenoid terminal and remove thru-bolts.

2. Remove two screws and communtator end frame (brush assembly and bearing will remain on armature).

3. Remove armature from field frame and frame and shield from drive end frame assembly.

A U T IO N !C N O T E

Make connections as shown. Close the switch and compare the rpm, current, and voltage readings with the values given in GM Service Bulletin 1M-88.

It is not necessary to obtain the exact voltage specified in these bulletins, as an accurate interpretation can be made by recognizing that if the voltage is slightly higher the rpm will be proportionately higher, with the current remaining essentially unchanged. However, if the exact voltage is desired, a carbon pile connected across the battery can be used to reduce the voltage to the specified value.

Caution: Magnets in frame have strong attraction to metal parts.

4. Use Proto Tools puller No. 4041 or equivalent to pull bearing from armature. The bearing is a press fit over shaft.

Interpret the test results as follows: 1. Rated current draw and no-load speed indicates normal condition of the cranking motor.

2. Low free speed and high current draw indicates: a. Too much friction -- tight, dry, or worn bearings, bent armature shaft allowing armature to drag. b. Shorted armature. This can be further checked on a growler after disassembly. c. Grounded armature. Check further after disassembly.

3. Failure to operate with high current draw indicates: a. A direct ground in the terminal or brush assembly. b. “Frozen” bearings (this should have been determined by turning the armature by hand).

4. Failure to operate with no current draw indicates: a. Open brush leads. b. Open armature coils. Inspect the commutator for badly burned bars after disassembly.

Note: Before removal lift brushes so spring rests against side of brush; this will prevent brush damage when brush assembly is pulled off of commutator. If springs are allowed to push brushes down when brush is moved off of commutator, the brush pigtail lead may be separated for the brush.

5. Slightly separate gear and drive assembly from drive end frame; use screwdriver to pry “plastic” shift lever off drive pins. Remove gear and drive from drive end frame.

6. To remove drive from shaft, remove collar, slide deep socket over shaft, tap socket to drive stop collar off snap ring. Remove snap ring and remove drive from shaft.

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Starter Motor

Component Inspection and Repair

Solenoid

Brushes and Brush Holders Inspect the brushes for wear. If they are worn excessively when compared with a new brush, they should be replaced. Make sure the brush holders are clean and the brushes are not binding in the holders.

The full brush surface should ride on the commutator to give proper performance. Check by hand to ensure that the brush springs are giving firm contact between the brushes and commutator. If the springs are distorted or discolored, they should be replaced.

Armature If commutator is rough or worn turn down only enough to clean the commutator surface. Do not undercut.

The armature should be checked for short circuits, opens, and grounds.

1. Short circuits are located by rotating the armature in a growler with a steel strip such as a hacksaw blade held on the armature. The steel strip will vibrate on the short circuit. Shorts between bars are sometimes produced by brush dust or copper between the bars.

2. Opens may be located by inspecting the points where the conductors are joined to the commutator for loose connections. Poor connections cause arcing and burning of the commutator. If commutator bars are black or discolored where windings are connected to bars, replace armature.

3. Grounds in the armature can be detected by the use of a test lamp. If the lamp lights when one test prod is placed on the commutator and the other test prod is place on the armature core or shaft, the armature is grounded.

With all leads disconnected from the solenoid, make test connections to the solenoid switch terminal and to ground, to check the hold-in winding.

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Starter Motor

Use the carbon pile across the battery to decrease the battery voltage to the value specified in GM Service Bulletin IS-188, and compare the ammeter reading with the specification. A high reading indicates a shorted or grounded hold-in winding, or grounded pullin winding, and a low reading excessive resistance.

N O T E A U T IO N !C

To check the pull-in winding, connect from the solenoid switch terminal (S), and to the solenoid motor (M) terminal.

Note: If needed to reduce the voltage to the specified value, connect the carbon pile between the battery and “M” terminal as shown in the dashed lines instead of across the battery as shown in solid lines. If not needed, connect a jumper directly from the battery to the “M” terminal as shown in dashed lines.

Bearing Replacement and Lubrication Install and lubricate bearings as follows. New prelubricated bearings normally do not require added lubricant.

1. Armature Commutator End Bearing a. Lift brushes up in holder with spring resting against side of brush. b. Place brush assembly over commutator. c. Press bearing inner race over shaft until inner race contacts stop shoulder. d. Bearing is sealed and requires no added lubrication. e. Lift springs to allow brushes to drop onto commutator.

2. Gear Bearing a. Press bearing to dimension shown.

Caution: To prevent overheating, do not leave the pull-in winding energized more than 15 seconds.

The current draw will decrease as the winding temperature increases.

Ammeter readings above the value specified in Service Bulletin IS-188 indicate shorted windings. A low reading indicates excessive resistance or an open.

b. Add lubricant P/N 10497186 to bearings if needed.

3. Drive End Housing Bearing a. Assemble bearings to dimension shown.

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Starter Motor

b. Add lubricant P/N 10497186 to bearings if needed.

4. Shaft Assembly Bearing a. Bearing and shaft are provided already assembled. b. Add lubricant P/N 10497186 if needed.

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.

Starter Assembly 1. Place lubricant P/N 10497186 on inner gear teeth, planetary gears, and armature shaft gear teeth.

2. Assemble inner gear and drive over shaft.

3. Place stop collar and snap ring on shaft. Using two pliers, squeeze collar and stop collar over snap ring.

4. Assemble drive and shaft assembly into drive end frame. Use screwdriver to gently guide shift lever over shift collar pins on drive assembly.

5. Assemble shield, field frame and armature to drive end frame.

A U T IO N !C

Caution: Field frame magnets have strong attraction to armature.

6. Attach commutator end frame to brush assembly with two screw bolts.

7. Assemble thru-bolts.

8. After motor assembly, visually check pinions for proper movement to engaged, then disengaged, position by momentarily connecting battery to solenoid “S” terminal and motor frame. Two or three checks will ensure that shift lever is properly located over shift collar pins.

A U T IO N !C

Caution: Secure motor in a vise, and keep hands away from pinion during test.

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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.

Fuel System - Gasoline Removal and Installation Removal steps 1. Nut 2. Washer - Spring 3. Washer 4. Seal - Oil 5. Hose 6. Bolt 7. Horn - Air 8. Bolt 9. Pipe - Fuel 10. Hose 11. Hose 12. Carburetor 13. Gasket 14. Nut 15. Hose 16. Hose 17. Adapter 18. Gasket - Adapter 19. Cable 20. Lever 21. Bracket 22. Motor - Step 23. Bracket - Motor

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Fuel Pump and Fuel Hose 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.

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Fuel Pump Disassembly and Reassembly

N N Disassembly Steps

N N N

N

1. Pump cover 2. Magnet 3. Cover gasket 4. Filter 5. Filter gasket 6. Pump body

A U T IO N !C

Main Point of Disassembly

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.

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Fuel Pump

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 12volt power source and try listening for clicks.

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 renew the 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 to see if no fuel leaks.

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Fuel System - LP Removal and Installation

N

N

N 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

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Fuel System - LP

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.

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.

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.

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.

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.

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Fuel System - LP

Impco Model VFF-30 Fuel Lock

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.

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Fuel System - LP

Vacuum Fuel Lock Service Procedures • The Impco VFF30 vacuum fuel filter lockoff is fully field serviceable.

• A repair kit is available (RK-VFF30) 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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Fuel System - LP

Model J Regulator

LPG Pressure Regulator 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 from Impco, 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.

N O T E

Use only genuine Impco replacement parts.

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Fuel System - LP

On-Vehicle Pressure Test

Regulator 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 the ITK-1, 0-5 psi gauge to the primary test port.

4. Remove secondary test port plug.

5. Install the ITK-1, 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. Flip 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. Remove the primary test port plug.

2. Connect the ITK-1, 0-5 psi gauge to the primary test port.

3. Connect compressed air to the fuel inlet.

4. Pressurize the regulator.

5. Note reading on pressure gauge.

6. Gauge reading should be approximately 1.5 psi.

7. 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.

LPG Pressure Regulator 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 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 or clamp hoses.

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.

LP Regulator/Lockout - Removal and Replacement GF4OK Disassembly Steps 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.

Fuel System - LP

Impco CA 100 Air Fuel Mixer

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 gasmetering valve is designed to maintain the correct air/fuel ratio over the entire operating range of the engine.

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 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.

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Fuel System - LP

Model CA100 Carburetor Repair Kit Installation Instructions

1. Screw 2. Cover 3. Spring, air valve 4. Screw *5. Plate, backup *6. Diaphragm *7. Ring, air valve *8. Air valve 9. Mixer body 10. Fitting 11. Screw, idle 12. Spring, idle screw 13. Plug 14. Gasket 15. Spacer 16. Adaptor 17. Air Valve Assembly * Components included in the Repair Kit.

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Fuel System - LP

Model CA100 Carburetor Repair Kit Installation 1. Remove the air valve cover and retaining screws.

Place a chalk mark on the air valve diaphragm and the mixer body. This mark will allow correct positioning during reassembly.

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.

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

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

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N O T E

Fuel System - LP

LPG Carburetor Adjustment Procedure CO/Exhaust Analyzer 1. Before starting make sure engine coolant and transmission oils are 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.

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. 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.

For console box without trans termperature gauge, warm truck up until engine coolant gauge is at block line or slightly above.

Governor Speed Adjustment Procedure 1. Set transmission in neutral position.

2. Press the accelerator pedal all the way to full open throttle.

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.

N O T E

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. 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%.

N O T E

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.

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 2700. If it is adjust the governor.

9. Power adjustment -- make sure truck is adequately secured, hold at converter stall full throttle, and adjust power valve until the CO emission level is a maximum of 1.0%.

-145-

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Please fax or mail completed form to: Mitsubishi Caterpillar Forklift America Inc. Attn: Technical Publications 2011 W. Sam Houston Parkway N. Houston, Texas 77043-2421 Fax: 713-365-1616

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Service Manual

GM 4.3L Gasoline Engine

Pub. No. 99789-84100

99789-84100

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