Yamaha F25C Service Manual - PDF DOWNLOAD

F25C

SERVICE MANUAL 290539

6D5-28197-5F-11

NOTICE This manual has been prepared by Yamaha primarily for use by Yamaha dealers and their trained mechanics when performing maintenance procedures and repairs to Yamaha equipment. It has been written to suit the needs of persons who have a basic understanding of the mechanical and electrical concepts and procedures inherent in the work, for without such knowledge attempted repairs or service to the equipment could render it unsafe or unfit for use.

Because Yamaha has a policy of continuously improving its products, models may differ in detail from the descriptions and illustrations given in this publication. Use only the latest edition of this manual. Authorized Yamaha dealers are notified periodically of modifications and significant changes in specifications and procedures, and these are incorporated in successive editions of this manual.

Important information

1

Particularly important information is distinguished in this manual by the following notations: The Safety Alert Symbol means ATTENTION! BECOME ALERT! YOUR SAFETY IS INVOLVED!

WARNING Failure to follow WARNING instructions could result in severe injury or death to the machine operator, a bystander, or a person inspecting or repairing the outboard motor.

CAUTION: A CAUTION indicates special precautions that must be taken to avoid damage to the outboard motor.

NOTE: A NOTE provides key information to make procedures easier or clearer.

F25C SERVICE MANUAL ©2003 by Yamaha Motor Co., Ltd. 1st Edition, November 2003 All rights reserved.

Any reprinting or unauthorized use without the written permission of Yamaha Motor Co., Ltd. is expressly prohibited.

Printed in Japan

Contents General information Specifications Periodic checks and adjustments Fuel system Power unit Lower unit Bracket unit

GEN INFO

SPEC

CHK ADJ

FUEL

POWR

LOWR

BRKT –

Electrical systems Troubleshooting Index

+

ELEC

TRBL SHTG

1 2 3 4 5 6 7 8 9

GEN INFO

General information How to use this manual ................................................................................. 1-1 Manual format............................................................................................ 1-1 Symbols..................................................................................................... 1-2 Safety while working......................................................................................1-3 Fire prevention........................................................................................... 1-3 Ventilation..................................................................................................1-3 Self-protection ........................................................................................... 1-3 Parts, lubricants, and sealants ..................................................................1-3 Good working practices .............................................................................1-4 Disassembly and assembly ....................................................................... 1-4 Identification...................................................................................................1-5 Applicable models .....................................................................................1-5 Serial number ............................................................................................ 1-5 Propeller selection ......................................................................................... 1-5 Propeller size............................................................................................. 1-5 Selection.................................................................................................... 1-6 Predelivery checks ........................................................................................1-6 Checking the fuel system ..........................................................................1-6 Checking the engine oil level..................................................................... 1-6 Checking the gear oil level ........................................................................ 1-6 Checking the outboard motor mounting height.......................................... 1-7 Checking the remote control cables (remote control model) ..................... 1-7 Checking the steering system ...................................................................1-8 Checking the gear shift and throttle operation...........................................1-8 Checking the engine stop lanyard switch .................................................. 1-9 Checking the cooling water pilot holes ......................................................1-9 Test run ..................................................................................................... 1-9 Break-in ................................................................................................... 1-10 After test run ............................................................................................ 1-10

6D55F11

1 2 3 4 5 6 7 8 9

GEN INFO

General information

How to use this manual

1

Manual format The format of this manual has been designed to make service procedures clear and easy to understand. Use the information below as a guide for effective and quality service.

1 Parts are shown and detailed in an exploded diagram and are listed in the components list.

2 Tightening torque specifications are provided in the exploded diagrams and after a numbered step with tightening instructions.

3 Symbols are used to indicate important aspects of a procedure, such as the grade of lubricant and lubrication point.

4 The components list consists of part names and part quantities, as well as bolt and screw dimensions.

5 Service points regarding removal, checking, and installation are shown in individual illustrations to explain the relevant procedure.

NOTE: For troubleshooting procedures, see Chapter 9, “Troubleshooting.”

LOWR

3

Lower unit

2

1

Lower unit

LOWR

Lower unit

Removing the drive shaft 1. Remove the drive shaft assembly and pinion, and then pull out the forward gear.

S62Y6740K

CAUTION: S62Y6850K

No.

Part name

Q’ty

1

Lower unit

1

2

Plastic tie

1

3

Hose

1

4

Check screw

1

5

Gasket

6

Dowel pin

2

7

Bolt

4

8

Drain screw

1

2

Not reusable

Disassembling the drive shaft

9

Grommet

1

Bolt

1

M10

11

Bolt

1

M8

12

Thrust washer

1

13

Propeller

1

14

Washer

1

Washer

1

16

Cotter pin

1

17

Propeller nut

1

18

Trim tab

1

6-5

1. Install the pinion nut 1, tighten it finger tight, and then remove the drive shaft bearing 2 using a press.

Not reusable

M10

10

15

Drive shaft holder 4 1: 90890-06518 Pinion nut holder 2: 90890-06505 Socket adapter 2 3: 90890-06507

Remarks

Do not reuse the bearing, always replace it with a new one.

Bearing separator 1: 90890-06534 2. Remove the needle bearing from the forward gear.

40 mm

45 mm 60 mm

CAUTION: CAUTION: • Do not press the drive shaft threads a directly.

• Do not reuse the bearing, always replace it with a new one.

Not reusable

Bearing inner race attachment 3: 90890-06639

62Y5A11

Do not reuse the bearing, always replace it with a new one.

Stopper guide plate 2: 90890-06501 Stopper guide stand 3: 90890-06538 Bearing puller 4: 90890-06535 Bearing puller claw 1 5: 90890-06536

Disassembling the forward gear 1. Remove the taper roller bearing from the forward gear using a press.

4

6-19

62Y5A11

5

1-1

6D55F11

How to use this manual

Symbols The symbols below are designed to indicate the content of a chapter.

General information

Fuel system

GEN INFO

Bracket unit

FUEL

Specifications

BRKT

Power unit

SPEC

Electrical systems

POWR

Periodic checks and adjustments Lower unit

CHK ADJ

–

ELEC

+

Troubleshooting

TRBL SHTG

LOWR

Symbols 1 to 6 indicate specific data.

1

2

3

4

5

6

T.

R.

1 2 3 4

5 Specified measurement 6 Specified electrical value (resistance, voltage, electric current)

Special tool Specified oil or fluid Specified engine speed Specified tightening torque

Symbols 7 to C in an exploded diagram indicate the grade of lubricant and the lubrication point.

7

8

9

0 A

E 7 8 9 0

A M

B D

C C

I

G

Apply Yamaha 4-stroke motor oil Apply gear oil Apply water resistant grease (Yamaha grease A) Apply molybdenum disulfide grease

A Apply corrosion resistant grease (Yamaha grease D) B Apply low temperature resistant grease (Yamaha grease C) C Apply injector grease

Symbols D to I in an exploded diagram indicate the type of sealant or locking agent and the application point.

D

E GM

F

4

D Apply Gasket Maker E Apply Yamabond No. 4 F Apply LOCTITE 271 (red) 6D55F11

G

H

I

LT

LT

LT

271

242

572

SS

G Apply LOCTITE 242 (blue) H Apply LOCTITE 572 I Apply silicon sealant

1-2

1 2 3 4 5 6 7 8 9

GEN INFO

General information

Safety while working

1

To prevent an accident or injury and to ensure quality service, follow the safety procedures provided below.

Fire prevention Gasoline is highly flammable.

Keep gasoline and all flammable products away from heat, sparks, and open flames.

Parts, lubricants, and sealants Use only genuine Yamaha parts, lubricants, and sealants or those recommended by Yamaha, when servicing or repairing the outboard motor.

Ventilation Gasoline vapor and exhaust gas are heavier than air and extremely poisonous. If inhaled in large quantities they may cause loss of consciousness and death within a short time.

When test running an engine indoors (e.g., in a water tank) be sure to do so where adequate ventilation can be maintained.

Under normal conditions, the lubricants mentioned in this manual should not harm or be hazardous to your skin. However, you should follow these precautions to minimize any risk when working with lubricants.

1. Maintain good standards of personal and industrial hygiene.

2. Change and wash clothing as soon as possible if soiled with lubricants.

Self-protection Protect your eyes by wearing safety glasses or safety goggles during all operations involving drilling and grinding, or when using an air compressor.

Protect your hands and feet by wearing protective gloves and safety shoes when necessary.

1-3

3. Avoid contact with skin. Do not, for example, place a soiled rag in your pocket.

4. Wash hands and any other part of the body thoroughly with soap and hot water after contact with a lubricant or lubricant soiled clothing has been made.

5. To protect your skin, apply a protective cream to your hands before working on the outboard motor.

6D55F11

Safety while working 6. Keep a supply of clean, lint-free cloths for wiping up spills, etc.

Disassembly and assembly 1. Use compressed air to remove dust and dirt during disassembly.

Good working practices Special service tools Use the recommended special service tools to protect parts from damage. Use the right tool in the right manner—do not improvise.

Tightening torques Follow the tightening torque specifications provided throughout the manual. When tightening nuts, bolts, and screws, tighten the large sizes first, and tighten fasteners starting in the center and moving outward.

Non-reusable parts Always use new gaskets, seals, O-rings, cotter pins, circlips, etc., when installing or assembling parts.

6D55F11

2. Apply engine oil to the contact surfaces of moving parts before assembly.

3. Install bearings with the manufacture identification mark in the direction indicated in the installation procedure. In addition, be sure to lubricate the bearings liberally.

4. Apply a thin coat of water-resistant grease to the lip and periphery of an oil seal before installation.

5. Check that moving parts operate normally after assembly.

1-4

1 2 3 4 5 6 7 8 9

GEN INFO

General information

Identification

1

Applicable models This manual covers the following models.

Applicable models F25CMH, F25CM

Serial number The outboard motor serial number is stamped on a label attached to the port clamp bracket.

Propeller selection

1

The performance of a boat and outboard motor will be critically affected by the size and type of propeller you choose. Propellers greatly affect boat speed, acceleration, engine life, fuel economy, and even boating and steering capabilities. An incorrect choice could adversely affect performance and could also seriously damage the engine.

Use the following information as a guide for selecting a propeller that meets the operating conditions of the boat and the outboard motor.

Propeller size The size of the propeller is indicated on a propeller blade, on the propeller boss end, on the side of the propeller boss.

×

a

-

b c

S69W1030

1 2 3 4

×

Model name Approved model code Transom height Serial number

Model name F25CMH F25CM

Approved model code

a

-

b c

Starting serial No.

S69W1040

S: 1000001– 6D5

L: 1000001– L: 1000001– ×

a

-

b c S69W1050

1-5

6D55F11

Identification / Propeller selection / Predelivery checks a Propeller diameter (in inches) b Propeller pitch (in inches) c Propeller type (propeller mark)

CAUTION: This is a 4-stroke engine. Never use premixed fuel.

Selection When the engine speed is at the full throttle operating range (5,000–6,000 r/min), the ideal propeller for the boat is one that provides maximum performance in relation to boat speed and fuel consumption.

Propeller size (in)

Checking the engine oil level 1. Check the engine oil level.

Material

9 7/8 × 8 - F 9 7/8 × 9 - F 9 7/8 × 10 1/2 - F 9 7/8 × 11 1/4 - F

Aluminum

9 7/8 × 12 - F 9 7/8 × 13 - F 9 7/8 × 14 - F

Predelivery checks

1

To make the delivery process smooth and efficient, the predelivery checks should be completed as explained below.

Checking the fuel system 1. Check that the fuel hoses are securely connected and that the fuel tank is full with fuel.

NOTE: If the engine oil is below the minimum level mark b, add sufficient oil until the level is between a and b.

Recommended engine oil: 4-stroke motor oil API: SE, SF, SG, SH, or SJ SAE: 10W-30 or 10W-40 Oil quantity: With oil filter replacement: 1.9 L (2.0 US qt, 1.7 Imp qt)

Checking the gear oil level 1. Check the gear oil level.

S60V1290

6D55F11

1-6

1 2 3 4 5 6 7 8 9

GEN INFO

General information

Checking the outboard motor mounting height 1. Check that the anti-cavitation plate is between the bottom of the boat and a maximum of 25 mm (1 in) a below it. If the mounting height is too high, cavitation will occur and propulsion will be reduced. Also, the engine speed will increase abnormally and cause the engine to overheat. If the mounting height is too low, water resistance will increase and reduce engine efficiency.

2

1

S6D51040

3. Check that the shift link lever 3 is vertical to the mating surfaces of the engine.

a S6D51030

NOTE: The optimum mounting height is affected by the combination of the boat and the outboard motor. To determine the optimum mounting height, test run the outboard motor at different heights.

a 2. Check that the clamp brackets are secured with the clamp screws.

Checking the remote control cables (remote control model) 1. Set the remote control lever to the neutral position and fully close the throttle lever.

S6D53190

WARNING The shift/throttle cable joint must be screwed in a minimum of 8.0 mm (0.31 in) a.

2. Check that the throttle cam 1 contacts the fully closed stopper 2.

1-7

6D55F11

Predelivery checks

Checking the steering system 1. Check the steering friction for proper adjustment.

N

% 100

steering

R

FAST

the

2. Check that the throttle operates smoothly when the throttle grip (tiller handle model) is turned from the fully closed position to the fully open position a.

Check that the throttle operates smoothly when the remote control lever (remote control model) is shifted from forward or reverse to the fully open positions a.

0

2. Check that smoothly.

1. Check that the gear shift operates smoothly when the remote control lever or shift lever is shifted from neutral to forward or reverse.

START

NOTE: • To increase the friction, turn the friction adjusting bolt in direction a.

• To decrease the friction, turn the friction adjusting bolt in direction b.

Checking the gear shift and throttle operation

F

operates

a

S6D51090

N F

R a

S6D51070

a S6D51130

S6D51080

3. Check that there is no interference with wires or hoses when the outboard motor is steered.

6D55F11

1-8

1 2 3 4 5 6 7 8 9

GEN INFO

General information

Checking the engine stop lanyard switch

Checking the cooling water pilot holes

1. Check that the engine turns off when the engine stop lanyard switch is pushed or the engine stop lanyard is pulled from the engine stop lanyard switch.

1. Check that cooling water is discharged from the cooling water pilot holes.

S6D53140

S6D51100

Test run 1. Start the engine, and then check that the gear shift operates smoothly.

2. Check the engine idle speed after the engine has been warmed up.

3. Operate at trolling speed.

S6D51110

4. Run the outboard motor for 1 hour at 2,000 r/min or at half throttle, then for another hour at 3,000 r/min or at 3/4 throttle.

5. Check that the outboard motor does not tilt up when shifting into reverse and that water does not flow in over the transom.

NOTE: The test run is part of the break-in operation.

È To outboard motor

1-9

6D55F11

Predelivery checks

Break-in During the test run, perform the break-in operation in the following three stages.

1. One hour a at 2,000 r/min or at approximately half throttle

1 2 3 4 5 6 7 8 9

2. One hour b at 3,000 r/min or 3/4 throttle and 1 minute out of every 10 at full throttle 3. Eight hours c at any speed, however, avoid running at full speed for more than 5 minutes

a È 0

b

1

c

2

10

S69J1240

È Hour

After test run 1. Check for water in the gear oil.

2. Check for fuel leakage in the cowling.

3. Flush the cooling water passage with fresh water using the flushing kit and with the engine running at idle.

6D55F11

1-10

GEN INFO

General information

— MEMO —

1-11

6D55F11

SPEC

Specifications General specifications................................................................................... 2-1 Maintenance specification ............................................................................2-3 Power unit..................................................................................................2-3 Lower unit ..................................................................................................2-7 Electrical .................................................................................................... 2-7 Dimensions................................................................................................2-9 Tightening torques....................................................................................... 2-11 Specified torques.....................................................................................2-11 General torques....................................................................................... 2-13

6D55F11

1 2 3 4 5 6 7 8 9

SPEC

Specifications

General specifications Item Dimension Overall length Overall width Overall height (S) (L) Boat transom height (S) (L) Weight (with aluminium propeller) (S) (L) Performance Maximum output Full throttle operating range Maximum fuel consumption Engine idle speed Power unit Type Cylinder quantity Total displacement Bore × stroke Compression ratio Control system Starting system Enrichment system Ignition system Maximum generator output Spark plug Cooling system Exhaust system Lubrication system

2-1

2

Unit

Model F25CMH

F25CM

mm (in) mm (in)

1,151 (45.3) 430 (16.9)

703 (27.7) 376 (14.8)

mm (in) mm (in)

1,148 (45.2)

—

mm (in) mm (in)

381 (15.0)

kg (lb) kg (lb)

62.0 (137) 64.0 (141)

kW (hp) r/min L (US gal, lmp gal)/hr r/min

cm3 (cu. in) mm (in)

V, W

1,275 (50.2) — 508 (20.0)

— 63.0 (139)

18.4 (25.0) at 5,500 r/min 5,000–6,000 9.2 (2.4, 2.0) at 6,000 r/min 925–1,025 In-line, 4-stroke, SOHC, 4 valves L2 498 (30.4) 65.0 × 75.0 (2.56 × 2.95) 9.87 Tiller handle Remote control Manual Prime Start Microcomputer (CDI) 12, 80 DPR6EA-9 (NGK) Water Propeller boss Wet sump

6D55F11

General specifications Item Fuel and oil Fuel type Fuel minimum rating Engine oil Engine oil grade Engine oil quantity (without oil filter replacement) (with oil filter replacement) Gear oil type Gear oil grade(*2) Gear oil quantity Bracket unit Tilt angle (at 12° boat transom) Tilt-up angle Shallow water drive angle Steering angle Drive unit Gear shift positions Gear ratio Reduction gear type Clutch type Propeller shaft type Propeller direction (rear view) Propeller identification mark (*1) (*2)

Unit

RON(*1) API SAE L (US qt, lmp qt) L (US qt, lmp qt) API SAE cm3 (US oz, lmp oz)

Model F25CMH

F25CM

1 2 3 4 5 6 7 8 9

Regular unleaded gasoline 86 4-stroke motor oil SE, SF, SG, SH, or SJ 10W-30 or 10W-40 1.7 (1.8, 1.5) 1.9 (2.0, 1.7) Hypoid gear oil GL-4 90 320 (10.8, 11.3)

Degree

8, 12, 16, 20, 24

Degree Degree Degree

64 29, 43 45 + 45 F-N-R 2.08 (27/13) Spiral bevel gear Dog clutch Spline Clockwise F

RON: Research Octane Number Meeting both API and SAE requirements

6D55F11

2-2

SPEC

Specifications

Maintenance specification

2

Power unit Item Power unit Minimum compression pressure(*1) Lubrication oil pressure(*2) Cylinder heads Warpage limit

(lines indicate straightedge position) Cylinder head journal inside diameter Cylinders Bore size Taper limit Out-of-round limit Pistons Piston diameter (D) Measuring point (H) Piston-to-cylinder clearance Piston pin boss bore Oversize piston diameter 1st 2nd Piston pins Outside diameter

Unit kPa (kgf/cm2, psi) kPa (kgf/cm2, psi)

Model F25CMH

F25CM 810 (8.1, 115)

80 (0.8, 11) at engine idle speed

mm (in)

0.10 (0.0039)

mm (in)

37.000–37.025 (1.4567–1.4577)

mm (in) mm (in) mm (in)

65.000–65.015 (2.5590–2.5596) 0.08 (0.0032) 0.05 (0.0020)

mm (in) mm (in) mm (in) mm (in)

64.950–64.965 (2.5571–2.5577) 2.0 (0.08) 0.035–0.065 (0.0014–0.0026) 15.974–15.985 (0.6289–0.6293)

mm (in) mm (in)

65.200–65.215 (2.5669–2.5675) 65.450–65.465 (2.5768–2.5774)

mm (in)

15.965–15.970 (0.6285–0.6287)

(*1)

Measure conditions: • Ambient temperature 20 °C (68 °F), wide open throttle, with spark plugs removed from all cylinders.

The figures are for reference only.

• Since this outboard motor is equipped with an automatic decompression mechanism, accurate data may be difficult to obtain due to differences in the way the starer rope is pulled. (*2) The figures are for reference only.

2-3

6D55F11

Maintenance specification Item Piston rings Top ring Dimension B Dimension T End gap Side clearance Oversize diameter 1st 2nd 2nd ring Dimension B Dimension T End gap Side clearance Oversize diameter 1st 2nd Oil ring Dimension B Dimension T End gap Side clearance Oversize diameter 1st 2nd Camshafts Intake and exhaust (A) Intake and exhaust (B) Camshaft journal diameter (top) Camshaft journal diameter (center) Camshaft journal oil clearance Camshaft runout limit Rocker arm shaft Rocker arm shaft outside diameter Rocker arms Rocker arm inside diameter

6D55F11

Unit

Model F25CMH

F25CM

mm (in) mm (in) mm (in) mm (in)

1.17–1.19 (0.0461–0.0469) 2.25–2.45 (0.0885–0.0965) 0.15–0.30 (0.0059–0.0118) 0.02–0.06 (0.0008–0.0024)

mm (in) mm (in)

65.250 (2.5689) 65.500 (2.5787)

mm (in) mm (in) mm (in) mm (in)

1.47–1.49 (0.0579–0.0587) 2.60–2.80 (0.1024–0.1102) 0.30–0.50 (0.0118–0.0197) 0.02–0.06 (0.0008–0.0024)

mm (in) mm (in)

65.250 (2.5689) 65.500 (2.5787)

mm (in) mm (in) mm (in) mm (in)

2.36–2.48 (0.0929–0.0976) 2.75 (0.1083) 0.20–0.70 (0.0079–0.0276) 0.04–0.18 (0.0016–0.0070)

mm (in) mm (in)

65.250 (2.5689) 65.500 (2.5787)

mm (in)

30.834–31.034 (1.2139–1.2218)

mm (in)

25.90–26.10 (1.0197–1.0276)

mm (in)

36.925–36.945 (1.4537–1.4545)

mm (in)

36.935–36.955 (1.4541–1.4549)

mm (in) mm (in)

0.050–0.090 (0.0020–0.0035) 0.03 (0.0012)

mm (in)

15.971–15.991 (0.6288–0.6296)

mm (in)

16.000–16.018 (0.6299–0.6306)

1 2 3 4 5 6 7 8 9 2-4

SPEC

Specifications Item

Valves Valve clearance (cold) Intake Exhaust Head diameter (A) Intake Exhaust Face width (B) Intake Exhaust Seat contact width (C) Intake and exhaust Margin thickness (D) Intake Exhaust Stem diameter Intake Exhaust Guide inside diameter Intake and exhaust Stem-to-guide clearance Intake and exhaust Stem runout limit Valve springs Free length Minimum free length Tilt limit Connecting rods Small-end inside diameter Big-end inside diameter Crankpin oil clearance Big-end bearing thickness A Blue B Black C Brown Crankshaft Crankshaft journal diameter Crankpin diameter Crankpin width Runout limit

2-5

Unit

Model F25CMH

F25CM

mm (in) mm (in)

0.15–0.25 (0.006–0.010) 0.25–0.35 (0.010–0.014)

mm (in) mm (in)

31.90–32.10 (1.256–1.264) 25.90–26.10 (1.020–1.028)

mm (in) mm (in)

1.84–2.97 (0.072–0.117) 1.98–3.11 (0.078–0.122)

mm (in)

0.9–1.1 (0.035–0.043)

mm (in) mm (in)

0.8 (0.0315) 0.9 (0.0354)

mm (in) mm (in)

5.475–5.490 (0.2156–0.2161) 5.460–5.475 (0.2150–0.2156)

mm (in)

5.500–5.512 (0.2165–0.2170)

mm (in) mm (in)

0.025–0.052 (0.0010–0.0020) 0.03 (0.0012)

mm (in) mm (in) mm (in)

39.85 (1.5689) 25.80 (1.0157) 1.7 (0.07)

mm (in) mm (in) mm (in)

15.985–15.998 (0.6293–0.6298) 36.000–36.024 (1.4173–1.4183) 0.020–0.052 (0.0008–0.0020)

mm (in) mm (in) mm (in)

1.494–1.498 (0.0588–0.0590) 1.490–1.494 (0.0587–0.0588) 1.486–1.490 (0.0585–0.0587)

mm (in) mm (in) mm (in) mm (in)

42.984–43.000 (1.6923–1.6929) 32.984–33.000 (1.2986–1.2992) 21.000–21.070 (0.8268–0.8295) 0.05 (0.0020)

6D55F11

Maintenance specification Item Crankcase Crankshaft main journal oil clearance Crankcase main journal bearing thickness A Blue B Black C Brown Oil pump Type Outer rotor-to-housing clearance Outer rotor-to-inner rotor clearance limit Rotor-to-cover clearance Relief valve operating pressure Thermostats Opening temperature Fully open temperature Valve open lower limit Fuel pump Discharge Pressure Plunger stroke Carburetor Identification mark Main jet Pilot jet Pilot screw Float height Manual starter Starter rope length

6D55F11

Unit

Model F25CMH

F25CM

mm (in)

0.012–0.044 (0.0005–0.0017)

mm (in) mm (in) mm (in)

1.498–1.502 (0.0590–0.0591) 1.494–1.498 (0.0588–0.0590) 1.490–1.494 (0.0587–0.0588)

mm (in)

Trochoid 0.09–0.15 (0.0035–0.0059)

mm (in)

0.12 (0.047)

mm (in) kPa (kgf/cm2, psi)

0.03–0.08 (0.0012–0.0031) 382–442 (3.82–4.42, 55.4–64.1)

°C (°F) °C (°F) mm (in)

58–62 (136–144) 70 (158) 3.0 (0.12)

L (US gal, lmp gal)/hr kPa (kgf/cm2, psi) mm (in)

70 (18.5, 15.4) at 3,000 r/min

1 2 3 4 5 6 7 8 9

49 (0.49, 7.1) 5.85–9.65 (0.23–0.38)

# # turns out mm (in)

65W11 112 50 1 5/8–2 5/8 8.7–9.7 (0.34–0.38)

mm (in)

1,625–1,727 (63.98–67.99)

2-6

SPEC

Specifications

Lower unit Item Gear backlash Pinion-to-forward gear Pinion-to-reverse gear Pinion shims Forward gear shims Reverse gear shims

Unit mm (in) mm (in) mm mm mm

Model F25CMH

F25CM

0.30–0.72 (0.0118–0.0283) 0.92–1.65 (0.0362–0.0650) 0.7, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6 1.0, 1.1, 1.2, 1.3, 1.4 1.0, 1.1, 1.2, 1.3

Electrical Item Ignition and ignition control system Ignition timing (cylinder #1) Spark plug gap Ignition coil resistance Primary coil (O – B) at 20 °C (68 °F) Secondary coil (spark plug wire – spark plug wire) at 20 °C (68 °F) CDI unit output peak voltage (B/W – O) at cranking (loaded) at 1,500 r/min (loaded) at 3,500 r/min (loaded) Pulser coil output peak voltage (R – W) at cranking (unloaded) at cranking (loaded) at 1,500 r/min (loaded) at 3,500 r/min (loaded) Pulser coil resistance(*1) (R – W) (*1)

Unit

Model F25CMH

F25CM

Degree Degree mm (in)

BTDC 8.5 at engine idle speed BTDC 30 at 6,000 r/min 0.8–0.9 (0.031–0.035)

Ω

0.08–0.11

kΩ

3.4–4.7

V V V

120.0 120.0 130.0

V V V V Ω

6.0 5.7 14.0 20.4 300–350

The figures are for reference only.

2-7

6D55F11

Maintenance specification Item Charge coil output peak voltage (G/W – W/G) at cranking (unloaded) at cranking (loaded) at 1,500 r/min (loaded) at 3,500 r/min (loaded) Charge coil resistance(*1) (G/W – W/G) at 20 °C (68 °F) Power bobbin output peak voltage (Y/B – Y/B) at cranking (unloaded) at 1,500 r/min (unloaded) at 3,500 r/min (unloaded) at cranking (loaded) at 1,500 r/min (loaded) at 3,500 r/min (loaded) Power bobbin resistance(*1) (Y/B – Y/B) at 20 °C (68 °F) Lighting coil output peak voltage (Y – Y) at cranking (unloaded) at 1,500 r/min (unloaded) at 3,500 r/min (unloaded) Lighting coil resistance(*1) (Y – Y) at 20 °C (68 °F) Enrichment control system Prime Start

Plunger extended length a(*1) Prime Start resistance(*2) (Y – Y) at 20 °C (68 °F) (*1) (*2)

Unit

Model F25CMH

F25CM

V V V V

170.0 130.0 140.0 140.0

Ω

660–710

V V V V V V

10.0 38.9 80.0 5.5 30.0 80.0

Ω

6.50–7.20

V V V

9.4 46.0 95.0

Ω

0.90–1.10

mm (in)

10.7–15.4 (0.42–0.61)

Ω

17.7–18.7

1 2 3 4 5 6 7 8 9

The figures are for reference only.

Measuring condition: Prime Start plunger length is 10.7 mm (0.42 in).

The figures are for reference only.

6D55F11

2-8

SPEC

Specifications

Dimensions Exterior * Tiller handle model only

185 (7.3)

631 (24.8)*

222 (8.7)*

45˚

400 (15.7)

mm (in)

572 (22.5)*

S: 763 (30.0) L: 877 (34.5)

363 (14.3)* 296 (11.7)*

580 (22.8)

190 (7.5)*

22 (0.9)

64

˚

S: 84 ( L: 10 3.3) 2 (4.0 )

S: 615 (24.2) L: 686 (27.0)

37 (1.5)*

42 (1.7)

184 (7.2)*

441 (17.4) S: 423 (16.7) 144 (5.7) L: 550 (21.7)

S: 707 (27.8) L: 834 (32.8)

698 (27.5)

65 (2.6)

12˚ S: 43 (1.7) L: 34 (1.3)

4˚

432 (17.0) S6D52010

2-9

6D55F11

Maintenance specification Clamp bracket

1 2 3 4 5 6 7 8 9 6D55F11

2-10

SPEC

Specifications

Tightening torques

2

Specified torques Part to be tightened

Thread size

Fuel system Fuel pump mounting bolt Fuel pump screw Carburetor bracket bolt Throttle link rod screw Power unit Power unit mounting bolt Apron bolt Start-in-gear protection cable bolt Manual starter roller bolt Starter rope guide bolt Sheave drum bolt Starter pulley bolt Flywheel magnet nut Stator coil bolt Driven sprocket bolt Pulser coil bolt CDI unit bolt CDI unit bracket bolt Ignition coil bolt Cylinder head bolt

1st 2nd 1st 2nd

Spark plug Oil pump screw Rocker arm locknut Rocker arm shaft bolt Thermostat cover bolt Exhaust cover bolt Oil filter Oil filter union bolt Balancer cover bolt Balancer piston nut Crankcase bolt

Connecting rod bolt

2-11

M6 M5 M6 M4

8 3 8 1

0.8 0.3 0.8 0.1

5.9 2.2 5.9 0.7

M8 M6 M5 M6 M6 — M8 M20 M5 M10 M5 M6 M6 M6

21 10 5 8 3 15 25 157 6 38 5 5 5 8 6 12 23 46 17 4 14 18 7 6 12 18 40 12 157 6 12 15 30 6 17

2.1 1.0 0.5 0.8 0.3 1.5 2.5 15.7 0.6 3.8 0.5 0.5 0.5 0.8 0.6 1.2 2.3 4.6 1.7 0.4 1.4 1.8 0.7 0.6 1.2 1.8 4.0 1.2 15.7 0.6 1.2 1.5 3.0 0.6 1.7

15.5 7.4 3.7 5.9 2.2 11.1 18.4 115.8 4.4 28.0 3.7 3.7 3.7 5.9 4.4 8.9 17.0 34.0 12.5 3.0 10.3 13.3 5.2 4.4 8.9 13.3 29.5 8.9 115.8 4.4 8.9 11.1 22.1 4.4 12.5

M6 M9 — M6 M6 M8 M6

1st 2nd

M6 — — M6 M20

1st 2nd 1st 2nd 1st 2nd

Tightening torques N·m kgf·m ft·lb

M6 M8 M6

6D55F11

Tightening torques Part to be tightened Lower unit Gear oil drain screw Gear oil check screw Lower case mounting bolt Cooling water inlet cover screw Propeller nut Propeller shaft housing bolt Pinion nut Bracket unit Tiller handle bracket nut Self-locking nut Engine stop lanyard switch nut Exhaust manifold bolt Throttle grip screw Shift rod lever bracket bolt Spring hook bolt Shift rod lever spring bolt Retaining plate bolt Upper mounting nut Upper mount bolt Mount housing nut Steering friction bolt Engine oil drain bolt Upper case bolt Exhaust manifold bolt Baffle plate screw Self-locking nut Tilt stopper plate nut Grease nipple Tilt lever screw

6D55F11

Thread size

Tightening torques N·m kgf·m ft·lb

— — M10 M5 M14 M6 M10

9 9 37 4 34 11 50

0.9 0.9 3.7 0.4 3.4 1.1 5.0

6.6 6.6 27.3 3.0 25.1 8.1 36.9

M10 M10 — M6 M5 M6 M6 M6 M6 M8 M8 M10 M8 M14 M8 M6 M5 M22 M8 — M5

10 22 2 10 3 10 10 10 10 24 27 54 4 27 21 10 2 45 24 3 4

1.0 2.2 0.2 1.0 0.3 1.0 1.0 1.0 1.0 2.4 2.7 5.4 0.4 2.7 2.1 1.0 0.2 4.5 2.4 0.3 0.4

7.4 16.2 1.5 7.4 2.2 7.4 7.4 7.4 7.4 17.7 20.0 39.8 3.0 20.0 15.5 7.4 1.5 33.2 17.7 2.2 3.0

2-12

1 2 3 4 5 6 7 8 9

SPEC

Specifications

General torques This chart specifies tightening torques for standard fasteners with a standard ISO thread pitch. Tightening torque specifications for special components or assemblies are provided in applicable sections of this manual. To avoid warpage, tighten multi-fastener assemblies in a crisscross fashion and progressive stages until the specified torque is reached. Unless otherwise specified, torque specifications require clean, dry threads.

Components should be at room temperature.

Nut (A)

Bolt (B)

8 mm 10 mm 12 mm 14 mm 17 mm

M5 M6 M8 M10 M12

2-13

General torque specifications N·m kgf·m ft·lb 5 0.5 3.6 8 0.8 5.8 18 1.8 13 36 3.6 25 43 4.3 31

6D55F11

CHK ADJ

Periodic checks and adjustments Special service tools .....................................................................................3-1 Maintenance interval chart............................................................................3-2 Top cowling .................................................................................................... 3-3 Checking the top cowling...........................................................................3-3 Fuel system .................................................................................................... 3-3 Checking the fuel joint and fuel hoses (fuel joint-to-carburetor) ................ 3-3 Checking the fuel filter ............................................................................... 3-3 Power unit....................................................................................................... 3-4 Checking the engine oil .............................................................................3-4 Changing the engine oil.............................................................................3-4 Replacing the oil filter ................................................................................ 3-5 Checking the timing belt ............................................................................3-5 Checking the spark plugs ..........................................................................3-6 Checking the thermostat............................................................................3-6 Checking the cooling water passage.........................................................3-7 Control system ............................................................................................... 3-7 Adjusting the throttle link ...........................................................................3-7 Adjusting the throttle cables (tiller handle model)...................................... 3-8 Adjusting the throttle cable (remote control model) ...................................3-8 Checking the gear shift operation (tiller handle model) ............................. 3-9 Checking the gear shift operation (remote control model).........................3-9 Checking the start-in-gear protection ........................................................3-9 Checking the engine idle speed ..............................................................3-10 Checking the ignition timing..................................................................... 3-10 Bracket ..........................................................................................................3-11 Checking the tilt operation ....................................................................... 3-11 Lower unit ..................................................................................................... 3-11 Checking the gear oil level ...................................................................... 3-11 Changing the gear oil .............................................................................. 3-12 Checking the lower unit for air leakage ...................................................3-12 Checking the propeller............................................................................. 3-12 General..........................................................................................................3-13 Checking the anodes............................................................................... 3-13 Lubricating the outboard motor................................................................3-13

6D55F11

1 2 3 4 5 6 7 8 9

CHK ADJ

Periodic checks and adjustments

Special service tools

3

Oil filter wrench 90890-01426

Digital tachometer 90890-06760

Timing light 90890-03141

Leakage tester 90890-06840

3-1

6D55F11

Special service tools / Maintenance interval chart

Maintenance interval chart

3

Use the following chart as a guideline for general maintenance.

Adjust the maintenance intervals according to the operating conditions of the outboard motor.

Initial Item Anode (external) Anodes (internal) Cooling water passages Top cowling Fuel filter (can be disassembled) Fuel system Fuel tank (Yamaha portable tank) Gear oil Lubrication points Engine idle speed (carburetor models) Propeller and cotter pin Shift link/shift cable Thermostat Throttle link/throttle cable/ throttle pick-up timing Water pump Engine oil Oil filter (cartridge) Spark plug(s) Timing belt Valve clearance (OHC)

Remarks

Every

10 hours 50 hours 100 hours 200 hours (1 month) (3 months) (6 months) (1 year)

Check/replace Check/replace Clean Check Check/replace Check Check/clean Change Lubricate Check/adjust Check/replace Check/adjust Check Check/adjust Check Check/change Replace Clean/adjust/ replace Check/replace Check/adjust

NOTE: • When operating in salt water, turbid or muddy water, the engine should be flushed with clean water after each use.

• When using lead or high-sulfur gasoline, checking valve clearance may be required more frequently than every 100 hours.

Item Timing belt

6D55F11

Remarks

Every 500 hours (2.5 years) 1,000 hours (5 years)

Replace

3-2

1 2 3 4 5 6 7 8 9

CHK ADJ

Periodic checks and adjustments

Top cowling

3

Checking the top cowling 1. Check the fitting by pushing the cowling with both hands. Adjust if necessary.

Fuel system S6D53010

2. Loosen the nuts 1.

3. Move the hook 2 up or down slightly to adjust its position.

3

Checking the fuel joint and fuel hoses (fuel joint-to-carburetor) 1. Check the fuel hose connections and fuel joints for leaks. Replace if necessary.

Also, check the fuel filter 1, fuel pump 2, and carburetor 3 for leaks or deterioration. Replace if necessary.

a 3

2

1

2

1 b

S6D53020

NOTE: • To loosen the fitting, move the hook in direction a.

• To tighten the fitting, move the hook in direction b.

S6D53040

Checking the fuel filter 1. Check the fuel filter element 1 for dirt and residue and check the fuel filter cup 2 for foreign substances and cracks.

Clean the cup with straight gasoline and replace the element if necessary.

4. Tighten the nuts.

5. Check the fitting again and, if necessary, repeat steps 2–4.

6. Check the water separator drain holes for obstructions. Clean if necessary.

3-3

6D55F11

Top cowling / Fuel system / Power unit NOTE: Be sure not to spill any fuel when removing the fuel filter cup.

Power unit

3

Checking the engine oil 1. Place the outboard motor in an upright position.

2. Remove the engine oil dipstick, wipe it clean, and then insert it back into the oil filler hole.

3. Place a drain pan under the drain hole, and then remove the drain bolt 2 and let the oil drain completely.

3. Remove the dipstick again to check the oil level and to check the oil for discoloration and its viscosity.

2

S6D53080

NOTE: Be sure to clean up any oil spills.

1. Start the engine, warm it up, and then turn it off.

2. Remove the engine oil dipstick and oil filler cap 1.

R.

Changing the engine oil

4. Install the drain bolt, and then tighten it to the specified torque.

T.

NOTE: • Change the oil if it appears milky or dirty.

• If the engine oil is below the minimum level mark b, add sufficient oil until the level is between a and b.

Drain bolt: 27 N·m (2.7 kgf·m, 20.0 ft·lb)

5. Pour the specified amount of the recommended engine oil into the oil filler hole.

Recommended engine oil: 4-stroke motor oil API: SE, SF, SG, SH, or SJ SAE: 10W-30 or 10W-40 Oil quantity: Without oil filter replacement: 1.7 L (1.8 US qt, 1.5 Imp qt) 6. Install the oil filler cap and dipstick, and then start the engine and warm it up for 5 minutes.

6D55F11

3-4

1 2 3 4 5 6 7 8 9

CHK ADJ

Periodic checks and adjustments

7. Turn the engine off, and then check the oil level and correct it if necessary.

T. R.

Oil filter: 18 N·m (1.8 kgf·m, 13.3 ft·lb)

Replacing the oil filter 1. Drain the engine oil.

2. Place a rag under the oil filter 1, and then remove the oil filter using the oil filter wrench.

5. Pour the specified amount of the recommended engine oil into the oil filler hole.

Recommended engine oil: 4-stroke motor oil API: SE, SF, SG, SH, or SJ SAE: 10W-30 or 10W-40 Oil quantity: With oil filter replacement: 1.9 L (2.0 US qt, 1.7 Imp qt) 6. Install the oil filler cap and dipstick, and then start the engine and warm it up for 5 minutes.

NOTE: • Wait more than 5 minutes after turning the engine off to replace the oil filter.

• Be sure to clean up any oil spills.

Oil filter wrench: 90890-01426 3. Apply a thin coat of engine oil to the Oring of the new oil filter.

4. Install the oil filter, and then tighten it to the specified torque using the oil filter wrench.

7. Turn the engine off, and then check the oil level and correct it if necessary.

Checking the timing belt 1. Remove the manual starter.

2. While turning the flywheel magnet clockwise, check the interior and the exterior of the timing belt for cracks, damage, or wear. Replace if necessary.

3. Turn the flywheel magnet clockwise to transfer the slack of the timing belt from port to starboard, and then lightly hold the flywheel magnet in place.

4. Slightly push the timing belt with your finger between the drive gear and driven gear, and then measure the belt slack.

Replace the timing belt if above specification.

a

S6D53110

3-5

6D55F11

Power unit NOTE: The valve system of this model will not be damaged even if the timing belt breaks.

5. Install the spark plugs, tighten them finger tight, then to the specified torque using a spark plug wrench.

T. R.

Timing belt slack a: Within 13 mm (0.5 in)

Checking the spark plugs

Spark plug: 17 N·m (1.7 kgf·m, 12.5 ft·lb)

Checking the thermostat 1. Remove the cover 1 and thermostat 2.

1. Disconnect the spark plug caps, and then remove the spark plugs.

2. Clean the electrodes 1 with a spark plug cleaner or wire brush. Replace the spark plug if necessary.

2. Suspend the thermostat in a container of water.

3. Place a thermometer in the water and slowly heat the water.

3. Check the electrodes for erosion and excessive carbon or other deposits, and the gasket for damage. Replace the spark plug if necessary.

4. Check the spark plug gap a. Adjust if out of specification.

S69J5E40

Specified spark plug: DPR6EA-9 (NGK) Spark plug gap a: 0.8–0.9 mm (0.031–0.035 in)

6D55F11

3-6

1 2 3 4 5 6 7 8 9

CHK ADJ

Periodic checks and adjustments

4. Check the thermostat valve opening at the specified water temperatures.

Replace if out of specification.

3. Check for water flow at the cooling water pilot holes. If there is no water flow, check the cooling water passages inside the outboard motor.

S6D53140

Water temperature

Valve lift a

58–62 °C (136–144 °F)

0.05 mm (0.0020 in) (valve begins to lift)

above 70 °C (158 °F)

more than 3.0 mm (0.12 in)

Control system

3

Adjusting the throttle link NOTE: For tiller handle models, adjust the throttle link after adjusting the throttle cable.

1. Loosen the screw 1.

5. Install the thermostat and cover, and then tighten the cover bolts to the specified torque.

2. Turn the throttle cam 2 clockwise until it contacts the stopper 3, and then hold it in that position.

T. R.

Thermostat cover bolt: 7 N·m (0.7 kgf·m, 5.2 ft·lb)

Checking the cooling water passage 1. Check the cooling water inlet cover 1 and cooling water inlet for clogs. Clean if necessary.

1 1

S6D53130

2. Place the lower unit in water, and then start the engine.

3-7

NOTE: For remote control models, the throttle cam cannot be turned unless the remote control lever is shifted to forward.

3. Turn the throttle lever 4 clockwise so that the throttle valve is fully open.

4. Tighten the screw.

6D55F11

Power unit / Control system 5. Operate the throttle cam to check that the throttle valve fully opens and fully closes.

Adjusting the throttle cables (tiller handle model) 1. Turn the throttle grip to the fully open position.

2. Loosen the locknut 1, and then turn the adjusting nut 2 to adjust the throttle cable 3.

S6D53210

Adjusting the throttle cable (remote control model) 1. Loosen the locknut 1, remove the clip 2, and then disconnect the throttle cable joint 3.

3. Tighten the locknut.

1

2 3

2. Contact the throttle cam 4 to the stopper 5.

5

4

S6D53220

2 1 4. Turn the throttle grip to the fully close position.

5. Loosen the locknut 4, and then turn the adjusting nut 5 to adjust the throttle cable 6.

6. Tighten the locknut.

4

5

3

S6D53180

3. Adjust the position of the throttle cable joint until its hole is aligned with the set pin on the throttle cam.

a

6 S6D53310

7. Check the throttle grip for smooth operation and, if necessary, repeat steps 1–6.

S6D53190

WARNING The throttle cable joint must be screwed in a minimum of 8.0 mm (0.31 in) a.

4. Connect the cable joint, install the clip, and then tighten the locknut.

6D55F11

3-8

1 2 3 4 5 6 7 8 9

CHK ADJ

Periodic checks and adjustments

5. Check the throttle cable for smooth operation and, if necessary, repeat steps 1–4.

Checking the gear shift operation (tiller handle model) 1. Check that the gear shift operates smoothly when shifting it from neutral to forward or reverse. Adjust the adjusting nut 1 if necessary.

R

N

4. Adjust the position of the shift cable joint until its hole is aligned with the set pin on the shift link lever.

F

S6D53320

a S6D53190

WARNING

1

The shift cable joint must be screwed in a minimum of 8.0 mm (0.31 in) a.

S6D53330

Checking the gear shift operation (remote control model)

5. Connect the cable joint, install the clip, and then tighten the locknut.

1. Check that the gear shift operates smoothly when the remote control lever is shifted from neutral to forward or reverse. Adjust the shift cable length if necessary.

6. Check the gear shift for smooth operation and, if necessary, repeat steps 3–5.

Checking the start-in-gear protection CAUTION:

2. Shift the remote control lever to neutral.

NOTE: After shifting the remote control lever to neutral, check that the shift link lever 1 is vertical to the mating surfaces of the engine.

3. Loosen the locknut 2, remove the clip 3, and then disconnect the shift cable joint 4.

3-9

Be sure to remove the engine stop lanyard switch clip before checking the startin-gear protection.

1. Shift the remote control lever or shift lever to forward or reverse, then pull the starter handle.

2. Check the operation of the start-in-gear protection cable. If the starter rope can be pulled out normally, adjust the start-ingear protection cable.

6D55F11

Control system NOTE: If the starter rope cannot be pulled out, the start-in-gear protection is working correctly.

3. Turn the throttle stop screw 2 in direction a or b until the specified engine idle speed is obtained.

3. Shift the remote control lever or shift lever to neutral.

4. Loosen the bolt 1, and then adjust the plate 2 until the mark a on the cable connector is aligned with the mark b on the manual starter case.

5. Tighten the bolt.

NOTE: • To increase the idle speed, turn the throttle stop screw in direction a.

• To decrease the idle speed, turn the throttle stop screw in direction b.

Checking the ignition timing 1. Start the engine and warm it up for 5 minutes.

Checking the engine idle speed 1. Start the engine and warm it up for 5 minutes.

2. Attach the special service tool to spark plug wire #1 1, and then check the engine idle speed. Adjust if out of specification.

2. Attach the special service tool to spark plug wire #1, and then check the engine idle speed.

Digital tachometer: 90890-06760

Engine idle speed: 925–1,025 r/min

1 3. Attach the special service tool to spark plug wire #1.

S6D53150

Digital tachometer: 90890-06760

Engine idle speed: 925–1,025 r/min

6D55F11

Timing light: 90890-03141

3-10

1 2 3 4 5 6 7 8 9

CHK ADJ

Periodic checks and adjustments

4. Check that the a is specified timing on the flywheel magnet.

Lower unit Checking the gear oil level

Ignition timing at engine idle speed: BTDC 8.5°

Bracket

3

1. Fully tilt the outboard motor down.

3

2. Remove the check screw 1, and then check the gear oil level in the lower case.

Checking the tilt operation 1. Fully tilt the outboard motor up and down a few times and check the entire tilt range for smooth operation. Check the tilt mechanism if necessary.

1 S60V3320

NOTE: • If the oil is at the correct level, the oil should overflow out of the check hole when the check screw is removed.

• If necessary, add sufficient gear oil of the recommended type until it overflows out of the check hole.

3. Install the check screw.

S6D53360

2. Fully tilt the outboard motor up, then support it with the tilt stop lever 1 to check the lock mechanism of the lever.

3-11

6D55F11

Control system / Bracket / Lower unit

Changing the gear oil 1. Tilt the outboard motor up slightly.

2. Place a drain pan under the drain screw 1, remove the drain screw, then the check screw 2 and let the oil drain completely.

Checking the lower unit for air leakage 1. Remove the check screw 1, and then install the special service tool.

Leakage tester: 90890-06840 2. Apply the specified pressure to check that the pressure is maintained in the lower unit for at least 10 seconds.

3. Check the oil for metal and discoloration, and its viscosity. Check the internal parts of the lower case if necessary.

4. Insert a gear oil tube or gear oil pump into the drain hole and slowly fill the gear oil until oil flows out of the check hole and no air bubbles are visible.

CAUTION: Do not over pressurize the lower unit, otherwise the oil seals can be damaged.

NOTE: Cover the check hole with a rag when removing the special service tool from the lower unit.

Lower unit holding pressure: 100 kPa (1.0 kgf/cm2, 14 psi) 3. If pressure drops below specification, check the drive shaft and propeller shaft oil seals for damage.

Checking the propeller Recommended gear oil: Hypoid gear oil SAE: 90 Oil quantity: 320 cm3 (10.8 US oz, 11.3 Imp oz)

1. Check the propeller blades and splines for cracks, damage, or wear. Replace if necessary.

5. Install the check screw and quickly install the drain screw.

6D55F11

3-12

1 2 3 4 5 6 7 8 9

CHK ADJ

Periodic checks and adjustments

General

3

Checking the anodes 1. Check the anodes for scales, grease, or oil. Clean if necessary.

S6D53240

È A

CAUTION: Do not oil, grease, or paint the anodes, otherwise they will be ineffective.

S6D53290

2. Replace eroded.

the

anodes

if

excessively

Lubricating the outboard motor

È Tiller handle model

NOTE: Apply grease to the grease nipples until it flows from the bushings a.

1. Apply water resistant grease to the areas shown.

2. Apply corrosion resistant grease to the area shown.

A

S6D53260

3-13

6D55F11

FUEL

Fuel system Special service tools .....................................................................................4-1 Hose routing ...................................................................................................4-2 Fuel hoses and fuel filter............................................................................... 4-3 Fuel pump ....................................................................................................... 4-4 Checking the fuel pump.............................................................................4-5 Disassembling the fuel pump .................................................................... 4-5 Checking the diaphragms and valves........................................................4-6 Assembling the fuel pump ......................................................................... 4-6 Checking the fuel joint ............................................................................... 4-7 Carburetor unit ............................................................................................... 4-8 Carburetor....................................................................................................... 4-9 Removing the carburetor .........................................................................4-11 Checking the carburetor ..........................................................................4-11 Checking the Prime Start.........................................................................4-12 Assembling the carburetor....................................................................... 4-12 Adjusting the throttle stop screw..............................................................4-13

6D55F11

1 2 3 4 5 6 7 8 9

FUEL

Fuel system

Special service tools

4

Vacuum/pressure pump gauge set 90890-06756

4-1

6D55F11

Special service tools / Hose routing

Hose routing

4

1

2

1

3 1 4

5

5 3

2 1 4

1

3

4

2 S6D54010

1 2 3 4 5

Blowby hoses Fuel hose (fuel joint-to-fuel filter) Fuel hose (fuel filter-to-fuel pump) Fuel hose (fuel pump-to-carburetor) Pilot water hose

6D55F11

4-2

1 2 3 4 5 6 7 8 9

FUEL

Fuel system

Fuel hoses and fuel filter

No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

4-3

Part name Fuel joint Bolt Fuel hose Bolt Nut Bracket Fuel filter Fuel filter element O-ring Cup Fuel hose Fuel hose Fuel pump O-ring Bracket Bolt

4

Q’ty 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2

Remarks M6 × 25 mm M8 × 14 mm

Not reusable

Not reusable

M6 × 30 mm

6D55F11

Fuel hoses and fuel filter / Fuel pump

Fuel pump

No. 1 2 3 4 5 6 7 8 9 10 11 12

Part name Screw Cover Gasket Diaphragm Fuel pump body 2 assembly Nut Pin Plunger Spring Fuel pump body 1 Spring Diaphragm

6D55F11

4

Q’ty 4 1 1 1 1 4 1 1 1 1 1 1

1 2 3 4 5 6 7 8 9

Remarks ø5 × 43 mm Not reusable Not reusable

4-4

FUEL

Fuel system

Checking the fuel pump 1. Place a drain pan under the fuel hose connections, and then disconnect the fuel hoses from the fuel pump.

6. Apply the specified positive pressure and check that there is no air leakage. Disassemble the fuel pump if necessary.

2. Connect the special service tool to the fuel pump inlet.

3. Cover the fuel pump outlet with a finger, and then apply the specified positive pressure. Check that there is no air leakage.

NOTE: Assemble the fuel pump valves to the fuel pump body, and moisten the inside of the fuel pump with gasoline to ensure a good seal.

Specified pressure: 50 kPa (0.5 kgf/cm2, 7.3 psi) Vacuum/pressure pump gauge set: 90890-06756

Disassembling the fuel pump 1. Disassemble the fuel pump as shown.

Specified pressure: 50 kPa (0.5 kgf/cm2, 7.3 psi) 4. Apply the specified negative pressure and check that there is no air leakage.

Specified pressure: 30 kPa (0.3 kgf/cm2, 4.4 psi)

2. Push down on the plunger and the diaphragm, turn fuel pump body 1 1 approximately 90° to a position where the pin 2 can be removed easily, and then remove the pin.

5. Connect the special service tool to the fuel pump outlet.

4-5

6D55F11

Fuel pump

3. Turn fuel pump body 1 2 approximately 90°, and then push down on the plunger several times to make sure that the pin does not come out.

3. Slowly let up on the plunger and diaphragm, and then remove them.

Checking the diaphragms and valves 1. Check the diaphragms for tears and the valves for cracks. Replace if necessary.

Assembling the fuel pump

NOTE: Make sure that the gasket and diaphragm are kept in place through the assembly process.

NOTE: Clean the parts and soak the valves and the diaphragms in gasoline before assembly to obtain prompt operation of the fuel pump when starting the engine.

1. Align the plunger and diaphragm installation holes a, and then install the plunger into the diaphragm.

2. Push down on the plunger and the diaphragm, and then install the pin 1.

6D55F11

4-6

1 2 3 4 5 6 7 8 9

FUEL

Fuel system

Checking the fuel joint 1. Visually check the fuel hose connector for cracks or damage.

2. Connect the special service tool at the outlet of fuel hose connector.

3. Apply the specified pressure to check that the pressure is maintained for 10 seconds. Replace the fuel hose connector of necessary.

Vacuum/pressure pump gauge set: 90890-06756 Fuel hose connector holding pressure: 50 kPa (0.5 kgf/cm2, 7.3 psi)

4-7

6D55F11

Fuel pump / Carburetor unit

Carburetor unit

No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14

Part name Bolt Fuel hose Plastic tie Blowby hose Bolt Intake silencer Joint Seal O-ring Plate Bracket O-ring Spacer Carburetor

6D55F11

4

Q’ty 3 1 1 1 2 1 1 1 1 1 1 2 1 1

1 2 3 4 5 6 7 8 9

Remarks M6 × 25 mm Not reusable

M6 × 100 mm

Not reusable

Not reusable

4-8

FUEL

Fuel system

Carburetor

No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14

4-9

Part name Throttle link rod Screw Screw Retainer Prime Start O-ring Screw Cover Gasket Throttle stop screw Spring Pilot screw O-ring Spring

4

Q’ty 1 1 1 1 1 1 3 1 1 1 1 1 1 1

Remarks ø4 × 5 mm ø4 × 10 mm

Not reusable

ø4 × 10 mm Not reusable

Not reusable

6D55F11

Carburetor 4

No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

Part name Carburetor body Float chamber Gasket Plunger rod Plunger Spring Circlip Ball Drain screw Screw Screw Float Needle valve Main jet Main nozzle Plug Pilot jet

6D55F11

Q’ty 1 1 1 1 1 1 1 1 1 4 1 1 1 1 1 1 1

1 2 3 4 5 6 7 8 9

Remarks

Not reusable

ø4 × 13 mm ø4 × 7 mm

4-10

FUEL

Fuel system

Removing the carburetor 1. Remove the manual starter.

2. Disconnect the throttle link rod and Prime Start connectors.

3. Disconnect the fuel hose.

4. Disconnect the blowby hose 1.

CAUTION:

1

S6D54160

5. Remove the bolts 2, then the carburetor assembly 3.

• Direct the compressed air downward, otherwise cleaning solvent may be blown into your eyes or small parts of the carburetor may be blown off.

• Do not use steel wire for cleaning the jets, otherwise the jet diameters may be enlarged, which may seriously affect performance.

3. Check the main jet, pilot jet, and main nozzle for dirt or residue. Clean if necessary.

4. Check the pilot screw and needle valve for bends or wear. Replace if necessary.

6. Remove the intake silencer and bracket from the carburetor.

S6D54200

Checking the carburetor

5. Check the float for deterioration. Replace if necessary.

1. Check the air and fuel passages and jets, for dirt and foreign matter. Clean the carburetor body with a petroleum based solvent if necessary.

6. Measure the float height a. Replace the float and needle valve as a set, if out of specification.

2. Blow compressed air into all passages and jets.

4-11

6D55F11

Carburetor Prime Start plunger extended length a (reference data): 10.7–15.4 mm (0.42–0.61 in)

NOTE: • The float should be resting on the needle valve 1, but not compressing it.

• Take measurements at the float position shown opposite its pivoted side.

Float height a: 8.7–9.7 mm (0.34–0.38 in)

Checking the Prime Start 1. Measure the length of the Prime Start plunger.

2. Connect the Prime Start yellow (Y) leads to a 12 V battery as shown.

3. Measure the plunger length a after applying power for the times indicated in the following table. Replace if out of specification.

Time (min)

Length (mm [in])

0

10.7 (0.42)

1

12.6 (0.50)

3

14.1 (0.56)

5

14.8 (0.58)

7

15.3 (0.60)

10

15.4 (0.61)

4. Measure the prime start resistance when the prime start plunger length is 10.7 mm (0.42 in).

Prime Start resistance (reference data): Yellow (Y) – Yellow (Y) 17.7–18.7 Ω at 20 °C (68 °F)

Assembling the carburetor 1. Install the main nozzle 1, main jet 2, pilot jet 3, and plug 4 to the carburetor body as shown.

4

2

3 1

S6D54110

6D55F11

4-12

1 2 3 4 5 6 7 8 9

FUEL

Fuel system

2. Install the needle valve 5, float 6, float pin 7, and screw 8 as shown, and then the check the float for smooth operation.

7 5 8

6

S6D54120

NOTE: • Place the needle valve in the valve seat when installing the float to the carburetor body.

• Fit the float pin into the slit on the carburetor body and lock it with the screw.

3. Install the pilot screw 9, turn it in until it is lightly seated, then out the specified number of turns.

NOTE: For remote control models, the throttle cam cannot be turned unless the remote control lever is shifted to forward.

7. Turn the throttle lever B clockwise so that the throttle valve is fully open.

8. Tighten the screw C. 9. Operate the throttle cam to check that the throttle valve fully opens and fully closes.

Adjusting the throttle stop screw 1. Start the engine and warm it up for 5 minutes.

Engine idle speed: 925–1,025 r/min 2. Turn the throttle stop screw 1 in direction a or b until the specified engine idle speed is obtained.

Pilot screw setting: 1 5/8–2 5/8 turns out 4. Install the carburetor assembly.

5. Connect the throttle link rod to the carburetor throttle lever.

6. Turn the throttle cam 0 clockwise until it contacts the stopper A, and then hold it in that position.

4-13

6D55F11

Carburetor NOTE: • To increase the idle speed, turn the throttle stop screw in direction a.

• To decrease the idle speed, turn the throttle stop screw in direction b.

1 2 3 4 5 6 7 8 9

Engine idle speed: 925–1,025 r/min

6D55F11

4-14

POWR

Power unit Special service tools .....................................................................................5-1 Power unit....................................................................................................... 5-3 Checking the compression pressure .........................................................5-3 Checking the oil pressure ..........................................................................5-3 Checking the valve clearance.................................................................... 5-4 Disassembling the manual starter ........................................................... 5-13 Checking the spiral spring ....................................................................... 5-13 Measuring the starter rope ...................................................................... 5-13 Assembling the manual starter ................................................................5-13 Installing the starter rope .........................................................................5-14 Removing the timing belt and sprockets.................................................. 5-15 Checking the timing belt and sprockets...................................................5-17 Installing the sprockets and timing belt....................................................5-17 Removing the power unit.........................................................................5-18 Cylinder head ...............................................................................................5-20 Removing the cylinder head .................................................................... 5-23 Checking the valve springs...................................................................... 5-24 Checking the valves ................................................................................ 5-24 Checking the valve guides....................................................................... 5-25 Replacing the valve guides...................................................................... 5-25 Checking the valve seat ..........................................................................5-26 Refacing the valve seat ...........................................................................5-26 Checking the rocker arms and rocker arm shaft...................................... 5-28 Checking the camshaft ............................................................................5-29 Checking the cylinder head ..................................................................... 5-29 Checking the oil pump ............................................................................. 5-30 Installing the valves ................................................................................. 5-30 Installing the camshaft............................................................................. 5-31 Installing the rocker arm shaft assembly ................................................. 5-32 Installing the oil pump.............................................................................. 5-32

6D55F11

Cylinder block ..............................................................................................5-33 Disassembling the cylinder block ............................................................ 5-36 Checking the balancer............................................................................. 5-37 Checking the piston diameter .................................................................. 5-37 Checking the cylinder bore ...................................................................... 5-37 Checking the piston clearance ................................................................5-38 Checking the piston rings ........................................................................5-38 Checking the piston ring grooves ............................................................ 5-39 Checking the piston ring side clearance.................................................. 5-39 Checking the piston pin boss bore .......................................................... 5-39 Checking the piston pin ...........................................................................5-39 Checking the connecting rod small end inside diameter ......................... 5-40 Checking the connecting rod big end side clearance ..............................5-40 Checking the crankshaft ..........................................................................5-40 Checking the crankpin oil clearance........................................................ 5-41 Selecting the connecting rod bearing ......................................................5-42 Checking the crankshaft main journal oil clearance ................................5-42 Selecting the crankshaft main bearing ....................................................5-43 Assembling the pistons and cylinder block.............................................. 5-44 Installing the cylinder head ...................................................................... 5-47 Installing the power unit...........................................................................5-49

6D55F11

1 2 3 4 5 6 7 8 9

POWR

Power unit

Special service tools

5

Compression gauge 90890-03160

Valve spring compressor attachment 90890-06320

Flywheel holder 90890-06522

Valve guide remover/installer 90890-06801

Universal clutch holder 90890-04086

Valve guide reamer 90890-06804

Flywheel puller 90890-06521

Valve seat cutter holder 90890-06316

Valve spring compressor 90890-04019

Valve seat cutter 90890-06312, 90890-06315, 90890-06323, 90890-06325, 90890-06327, 90890-06328

5-1

6D55F11

Special service tools

1 2 3 4 5 6 7 8 9

Bearing outer race attachment 90890-06626

Driver rod LS 90890-06606

Oil filter wrench 90890-01426

Piston slider 90890-06529

6D55F11

5-2

POWR

Power unit

Power unit

5

Checking the compression pressure 1. Start the engine, warm it up for 5 minutes, and then turn it off.

2. Remove the clip from the engine stop lanyard switch.

3. Remove the spark plug caps and all spark plugs, and then install the special service tools into a spark plug hole.

5. If the compression pressure is below specification and the compression pressure for each cylinder is unbalanced, add a small amount of engine oil to the cylinder, and then check the pressure again.

NOTE: • If the compression pressure increases, check the pistons and piston rings for wear.

Replace if necessary.

• If the compression pressure does not increase, check the valve clearance, valve, valve seat, cylinder sleeve, cylinder head gasket, and cylinder head. Adjust or replace if necessary.

Checking the oil pressure 1. Place a rag under the oil pressure switch.

1 S6D55050

CAUTION: Before removing the spark plugs, blow compressed air in the spark plug well to clear out any dirt or dust that may fall into the cylinder.

2. Remove the oil pressure switch, and then install an oil pressure gauge 1 to the oil pressure switch installation hole.

1

Compression gauge 1: 90890-03160 S6D55060

4. Fully open the throttle, crank the engine until the reading on the compression gauge stabilizes, and then check the compression pressure.

NOTE: Since this outboard motor is equipped with an automatic decompression mechanism, accurate data may be difficult to obtain due to differences in the way the starter rope is pulled.

Minimum compression pressure (reference data): 810 kPa (8.1 kgf/cm2, 115 psi)

5-3

NOTE: Use a general pressure gauge.

3. Start the engine and warm it up for 5 minutes.

4. Check the oil pressure. Check the oil pump, oil leakage, and oil strainer if out of specification.

Oil pressure (reference data): 80 kPa (0.8 kgf/cm2, 11 psi) at engine idle speed

6D55F11

Power unit

Checking the valve clearance

7. Check the intake and exhaust valve clearances for cylinder #2. Adjust if out of specification.

1. Remove the manual starter.

2. Remove the fuel pump 1.

3. Disconnect the ignition coil connectors and spark plug caps 2 and remove the spark plugs and cylinder head cover 3.

3 2 1

S6D55070

4. Turn the flywheel magnet clockwise and align the “ ” mark a on the driven sprocket with the “ ” mark b on the cylinder head.

NOTE: • Check the valve clearance when the engine is cold.

• Note the measurement.

Valve clearance: Intake d: 0.15–0.25 mm (0.006–0.010 in) Exhaust e: 0.25–0.35 mm (0.010–0.014 in)

5. Check the intake and exhaust valve clearances for cylinder #1. Adjust if out of specification.

6. Turn the flywheel magnet clockwise and align the “ ” mark c on the driven sprocket with the “ ” mark b on the cylinder head.

6D55F11

5-4

1 2 3 4 5 6 7 8 9

POWR

Power unit

8. Loosen the rocker arm locknut 4, and then turn the adjusting screw 5 until the specified valve clearance is obtained.

4 f

5 g

S6D55100

NOTE: • To decrease the valve clearance, turn the adjusting screw in direction f.

• To increase the valve clearance, turn the adjusting screw in direction g.

9. Tighten the rocker arm locknut to the specified torque, and then check the valve clearance again. Adjust if necessary.

T. R.

Rocker arm locknut 4: 14 N·m (1.4 kgf·m, 10.3 ft·lb)

10. Install the cylinder head cover, fuel pump bolts, spark plugs, spark plug caps, and manual starter.

5-5

6D55F11

Power unit 5

No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

Part name Bolt Washer Clip Start-in-gear protection cable Bolt Manual starter Bolt Power unit Dipstick Dowel Bolt Gasket Bolt Apron Bolt

6D55F11

Q’ty 1 1 2 1 4 1 1 1 1 2 2 1 8 1 2

1 2 3 4 5 6 7 8 9

Remarks M5 × 13 mm

M6 × 25 mm M6 × 12 mm

M6 × 14 mm Not reusable

M8 × 80 mm M6 × 25 mm

5-6

POWR

Power unit 5

No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

5-7

Part name Bolt Starter pulley Nut Washer Flywheel magnet Spacer Bolt Stator coil Woodruff key Woodruff key Drive sprocket Driven sprocket Pulser coil Bolt Washer Bolt Timing belt

Q’ty 3 1 1 1 1 1 3 1 1 1 1 1 1 2 1 1 1

Remarks M8 × 12 mm

M5 × 25 mm

M5 × 16 mm M10 × 40 mm

6D55F11

Power unit 5

R.

R.

22

25

23 24

T.

T.

5 N • m (0.5 kgf • m, 3.7 ft • Ib)

8 N • m (0.8 kgf • m, 5.9 ft • Ib)

2 3

1

26

7

8

54

9 6 A

5

4

10

17

19 20 21

11

13

12

14

18 T.

R.

5 N • m (0.5 kgf • m, 3.7 ft • Ib)

15 16

S6D55040

No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

Part name Ignition coil Bolt Holder Grommet Spark plug cap Plastic tie Retainer Bolt Thermo sensor Oil pressure switch Cap Oil pressure switch lead Holder Bolt Bolt Wiring harness Bolt

6D55F11

Q’ty 1 2 1 2 2 2 1 1 1 1 1 1 1 1 1 1 3

Remarks M6 × 30 mm

Not reusable

M6 × 12 mm

M6 × 16 mm

M6 × 45 mm

5-8

1 2 3 4 5 6 7 8 9

POWR

Power unit 5

R.

R.

22

25

23 24

T.

T.

5 N • m (0.5 kgf • m, 3.7 ft • Ib)

8 N • m (0.8 kgf • m, 5.9 ft • Ib)

2 3

1

26

7

8

54

9 6 A

5

4

10

17

19 20 21

11

13

12

14

18 T.

R.

5 N • m (0.5 kgf • m, 3.7 ft • Ib)

15 16

S6D55040

No. 18 19 20 21 22 23 24 25 26

5-9

Part name CDI unit Bracket Bolt Holder Bolt Collar Grommet Bolt Holder

Q’ty 1 1 1 1 3 3 3 1 1

Remarks

M5 × 16 mm M6 × 25 mm

M6 × 16 mm

6D55F11

Power unit 5

No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14

Part name Bolt Washer Throttle control lever Spacer Throttle cam Bolt Bracket Bolt Washer Shift link lever Collar Shift link rod Washer Clip

6D55F11

Q’ty 1 1 1 1 1 1 1 1 1 1 1 1 1 1

1 2 3 4 5 6 7 8 9

Remarks M6 × 55 mm

M6 × 10 mm M6 × 25 mm, Remote control model Remote control model Remote control model Remote control model Remote control model Remote control model Remote control model

5-10

POWR

Power unit 5

1 2

T.

8 N • m (0.8 kgf • m, 5.9 ft • Ib)

30

R.

3 4

A

5

6 8

7

9 10 29 28

25 23 14

11

12

A

24 A

27

22

13

21

13

26

T.

R.

3 N • m (0.3 kgf • m, 2.2 ft • Ib) A

15 20 19

16 17 T.

R.

No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

5-11

15 N • m (1.5 kgf • m, 11.1 ft • Ib)

Part name Bolt Washer Roller Collar Manual starter case Guide Starter rope Nut Starter rope guide Damper Manual starter handle Cover Oil pressure warning indicator Bolt Spring Drive pawl Circlip

18 Q’ty 1 1 1 1 1 1 1 2 1 1 1 1 1 2 2 2 2

S6D55020

Remarks M6 × 30 mm

M6 × 20 mm

6D55F11

Power unit 5

1 2

T.

8 N • m (0.8 kgf • m, 5.9 ft • Ib)

30

R.

3 4

A

5

6 8

7

9 10 29 28

25 23 14

11

12

A

24 A

27

22

13

21

13

26

T.

R.

3 N • m (0.3 kgf • m, 2.2 ft • Ib)

15

A

20 19

16 17 T.

R.

No. 18 19 20 21 22 23 24 25 26 27 28 29 30

15 N • m (1.5 kgf • m, 11.1 ft • Ib)

Part name Bolt Drive plate Spring Sheave drum Cartridge spring Spring washer Lock cam base plate Spring Bolt Lock cam retainer Lock cam Spring Cover

6D55F11

18 Q’ty 1 1 1 1 1 1 1 1 3 1 1 1 1

S6D55020

Remarks

M5 × 25 mm

5-12

1 2 3 4 5 6 7 8 9

POWR

Power unit

Disassembling the manual starter

Measuring the starter rope

1. Remove the lock cam retainer, and then remove the lock cam base plate 1 and lock cam 2.

1. Measure the starter rope length. Replace if the length is out of specification.

Starter rope length: 1,625–1,727 mm (63.98–67.99 in)

1

Assembling the manual starter 1. Install the spring washer 1 and cartridge spring 2 into the manual starter case.

2

b

1

S6D55310

2. Remove the drive plate 3 and drive pawls 4.

a 2

c

3 S6D55340

4

4 S6D55320

3. Remove the sheave drum 5, cartridge spring 6, spring washer 7, and starter rope 8.

NOTE: • Install the spring washer with its projections a facing down towards the manual starter case.

• Position the end b of the cartridge spring into the indentation c in the manual starter case.

2. Install the sheave drum 3 into the manual starter case.

f

3 d

7 8

6

d e

5

S6D55330

Checking the spiral spring 1. Check the spiral spring for cracks, bends, or damage. Replace the cartridge spring if necessary.

5-13

S6D55350

NOTE: Position the projections d on the cartridge spring case and the end e of the cartridge spring into the indentations f in the sheave drum.

6D55F11

Power unit 3. Install the drive pawls 4.

4. Install the spring 5 and drive plate 6, and then tighten the bolt 7 to the specified torque.

3. Turn the sheave drum clockwise until the rope hole a and manual starter roller b are aligned. Hold the sheave drum in this position.

6

7

5 4

4 S6D55360

T. R.

Sheave drum bolt 7: 15 N·m (1.5 kgf·m, 11.1 ft·lb)

Installing the starter rope

NOTE: If the sheave drum is turned less than 90° (from where if stopped to where the rope hole and roller align), turn it one full turn clockwise until the hole and roller align again.

1. Tie a knot on the end of the starter rope.

4. Pass the starter rope 2 through the rope hole in the sheave drum and out through the manual starter case 3, and then install the starter rope to the manual starter handle 4.

NOTE: Tie a knot at the end of the starter rope as shown in the illustration.

2. Wind the sheave drum 1 counterclockwise until it stops.

NOTE: Be sure to leave 12–20 mm (0.47–0.79 in) at the end c of the starter rope.

6D55F11

5-14

1 2 3 4 5 6 7 8 9

POWR

Power unit

5. Pull the manual starter handle several times to check that the sheave drum turns smoothly and to check the starter rope for slack. Repeat steps 2–4 if necessary.

NOTE: When checking the manual starter operation, pull the manual starter handle while pushing the start-in-gear protection lock cam so that it contacts the sheave drum.

3. Remove the starter pulley 1.

6. Pull the manual starter handle to extend the starter rope completely, then measure the starter rope length. Adjust if the starter rope length is out of specification.

Universal clutch holder: 90890-04086 4. Loosen the flywheel magnet nut.

S6D55B10

Starter rope length (reference data): 1,470 mm (57.9 in)

Removing the timing belt and sprockets 1. Remove the manual starter.

2. Turn the flywheel magnet clockwise and align the “ ” mark a on the driven sprocket with the “ ” mark b on the cylinder head.

5-15

6D55F11

Power unit

CAUTION: Apply force in the direction of the arrows shown to prevent the flywheel holder from slipping off easily.

6. Disconnect the charge coil connectors and power bobbin connectors, and remove the stator coil 2.

Flywheel holder: 90890-06522 5. Remove the flywheel magnet, then the woodruff key.

7. Remove the timing belt 3 from the driven sprocket and then from the drive sprocket.

3

S6D55130

8. Remove the drive sprocket.

9. Remove the driven sprocket.

CAUTION: To prevent damage to the engine or tools, screw in the puller set bolts evenly and completely so that the puller plate is parallel to the flywheel magnet.

NOTE: Apply force to the crankshaft end until the flywheel magnet comes off the tapered portion of the crankshaft.

Flywheel holder: 90890-06522

Flywheel puller: 90890-06521

6D55F11

5-16

1 2 3 4 5 6 7 8 9

POWR

Power unit

Checking the timing belt and sprockets 1. Check the interior and exterior of the timing belt for cracks, damage, or wear.

Replace if necessary.

2. Check the drive sprocket and driven sprockets for cracks, damage, or wear.

Replace if necessary.

Installing the sprockets and timing belt 1. Install the driven sprocket 1, and then tighten the bolt to the specified torque.

4. Install a new timing belt 3 to the drive sprocket and then to the driven sprocket with its part number in the upright position.

3

Flywheel holder: 90890-06522 S6D55150

T. R.

Driven sprocket bolt: 38 N·m (3.8 kgf·m, 28.0 ft·lb)

2. Check that “ ” mark a on the driven sprocket is aligned with the “ ” mark b on the cylinder head. Align if necessary.

CAUTION: • Do not to damage the timing belt during installation.

• Do not twist, turn inside out, or bend the timing belt beyond the maximum limit of 25 mm (1.0 in), otherwise it can be damaged.

• Do not get oil or grease on the timing belt.

NOTE: When installing the timing belt, lift the drive sprocket slightly to ease installation. Be careful the Woodruff key for the drive sprocket does not slide out of position.

3. Install the drive sprocket 2, and then check that the mark c on the drive sprocket is aligned with the mark d on the cylinder block. Align if necessary.

5-17

5. Turn the drive sprocket clockwise two turns, and then check that the alignment marks are aligned.

6D55F11

Power unit NOTE: Do not turn the drive sprocket counterclockwise, otherwise the valve system may be damaged.

6. Install the stator coil, and connect the charge coil connectors and power bobbin connectors.

7. Install the Woodruff key, then the flywheel magnet.

Universal clutch holder: 90890-04086

T. R.

Starter pulley bolt: 25 N·m (2.5 kgf·m, 18.4 ft·lb)

9. Install the manual starter.

Removing the power unit

CAUTION: Apply force in the direction of the arrows shown to prevent the flywheel holder from slipping off easily.

NOTE: Apply engine oil to the flywheel magnet nut before installation.

NOTE: It is recommended to loosen the flywheel magnet nut before removing the power unit to improve working efficiency.

1. Remove the manual starter.

2. Disconnect the throttle cables (tiller handle model), or throttle cable and shift cable (remote control model).

3. Remove the blowby hose and dipstick.

Flywheel holder: 90890-06522

4. Disconnect the fuel hose, engine stop lanyard switch leads, and cooling water pilot hose.

T. R.

Flywheel magnet nut: 157 N·m (15.7 kgf·m, 115.8 ft·lb)

8. Install the starter pulley, and then tighten the bolts to the specified torque.

6D55F11

5-18

1 2 3 4 5 6 7 8 9

POWR

Power unit

5. Remove the apron 1, and then remove the power unit by removing the bolts 2.

6. Remove the flywheel magnet, then the woodruff key.

5-19

6D55F11

Power unit / Cylinder head

Cylinder head

No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

Part name Cylinder head Gasket Dowel Bolt Bolt O-ring O-ring O-ring Oil pump assembly Bolt Gasket Bolt Cylinder head cover O-ring Oil filler cap Bolt Plate

6D55F11

5

Q’ty 1 1 2 6 3 1 1 1 1 4 1 5 1 1 1 2 2

1 2 3 4 5 6 7 8 9

Remarks Not reusable

M9 × 95 mm M6 × 25 mm Not reusable Not reusable Not reusable

M6 × 35 mm Not reusable

M6 × 20 mm

M6 × 20 mm

5-20

POWR

Power unit 5

No. 18 19 20 21 22

5-21

Part name Cover Bolt Anode Grommet Spark plug

Q’ty 2 2 2 2 2

Remarks M5 × 12 mm

6D55F11

Cylinder head 5

No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

Part name Exhaust valve Intake valve Valve spring seat Valve seal Valve spring Valve spring retainer Valve cotter Rocker arm assembly Rocker arm retainer Bolt Stopper guide Tensioner Rocker arm shaft Retaining bolt Gasket Camshaft Oil seal

6D55F11

Q’ty 2 2 4 4 4 4 8 4 2 3 1 1 1 1 1 1 1

1 2 3 4 5 6 7 8 9

Remarks

Not reusable

M8 × 30 mm

Not reusable Not reusable

5-22

POWR

Power unit

Removing the cylinder head 1. Remove the cylinder head cover.

2. Remove the cylinder head bolts in the sequence shown.

$ # & ±

% !

S6D55450

6. Remove the intake and exhaust valves.

CAUTION: Do not scratch or damage the mating surfaces of the cylinder head and cylinder block.

3. Remove the oil pump assembly 1.

4. Remove the rocker arm assembly 2, and rocker arm shaft 3.

3 2

S6D55470

NOTE: Be sure to keep the valves, springs, and other parts in the order as they were removed.

Valve spring compressor 6: 90890-04019 Valve spring compressor attachment 7: 90890-06320

5. Remove the retaining bolt 4, then the camshaft 5.

5-23

6D55F11

Cylinder head

Checking the valve springs 1. Measure the valve spring free length a.

Replace if below specification.

Valve margin thickness a: Intake: 0.8 mm (0.0315 in) Exhaust: 0.9 mm (0.0354 in) 3. Measure the valve stem diameter b.

Replace if out of specification.

Valve spring free length a: 39.85 mm (1.5689 in) 2. Measure the valve spring tilt b. Replace if above specification.

Valve stem diameter b: Intake: 5.475–5.490 mm (0.2156–0.2161 in) Exhaust: 5.460–5.475 mm (0.2150–0.2156 in) 4. Measure the valve stem runout. Replace if above specification.

Valve spring tilt limit b: 1.7 mm (0.07 in)

Checking the valves 1. Check the valve face for pitting or wear.

Replace if necessary.

2. Measure the valve margin thickness a.

Replace if below specification.

Valve stem runout limit: 0.03 mm (0.0012 in)

6D55F11

5-24

1 2 3 4 5 6 7 8 9

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Power unit

Checking the valve guides NOTE: Before checking the valve guide make sure that the valve stem diameter is within specification.

1. Measure the valve guide inside diameter a.

Valve guide inside diameter a: Intake and exhaust: 5.500–5.512 mm (0.2165–0.2170 in) 2. Calculate the valve stem-to-valve guide clearance as follows. Replace the valve guide if out of specification.

Valve stem-to-valve guide clearance = valve guide inside diameter – valve stem diameter: Intake and exhaust: 0.025–0.052 mm (0.0010–0.0020 in)

Valve guide remover/installer: 90890-06801 2. Install a new valve guide 2 by striking the special service tool from the camshaft side until the valve guide clip 3 contacts the cylinder head.

NOTE: Apply engine oil to the surface of the new valve guide.

Valve guide remover/installer: 90890-06801 3. Insert the special service tool into the valve guide 2, and then ream the valve guide.

Replacing the valve guides 1. Remove the valve guide 1 by striking the special service tool from the combustion chamber side.

NOTE: • Turn the valve guide reamer clockwise to ream the valve guide.

• Do not turn the reamer counterclockwise when removing the reamer.

Valve guide reamer: 90890-06804

5-25

6D55F11

Cylinder head 4. Measure the valve guide inside diameter.

Valve guide inside diameter: Intake and exhaust: 5.500–5.512 mm (0.2165–0.2170 in)

Checking the valve seat 1. Eliminate carbon deposits from the valve with a scraper.

2. Apply a thin, even layer of Mechanic’s blueing dye (Dykem) onto the valve seat.

3. Lap the valve slowly on the valve seat with a valve lapper (commercially available) as shown.

Valve seat contact width a: Intake and exhaust: 0.9–1.1 mm (0.035–0.043 in)

Refacing the valve seat 1. Reface the valve seat with the valve seat cutters.

4. Measure the valve seat contact width a where the blueing dye is adhered to the valve face. Reface the valve seat if the valve is not seated properly or if the valve seat contact width is out of specification.

Replace the valve guide if the valve seat contact is uneven.

6D55F11

Valve seat cutter holder: 90890-06316 Valve seat cutter: 30° (intake): 90890-06327 30° (exhaust): 90890-06328 45° (intake): 90890-06325 45° (exhaust): 90890-06312 60° (intake): 90890-06323 60° (exhaust): 90890-06315

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Power unit

2. Cut the surface of the valve seat with a 45° cutter by turning the cutter clockwise until the valve seat face has become smooth.

b

60˚ S69J5890

b Previous contact width

S6D55540

5. Use a 45° cutter to adjust the contact width of the valve seat to specification.

b c

45˚ S69J5900

b Previous contact width c Specified contact width

a Slag or rough surface

CAUTION: Do not over cut the valve seat. Be sure to turn the cutter evenly downward at a pressure of 40–50 N (4–5 kgf, 8.8–11 lbf) to prevent chatter marks.

6. If the valve seat contact area is too wide and situated in the center of the valve face, use a 30° cutter to cut the top edge of the valve seat and a 60° cutter to cut the bottom edge to center the area and set its width.

3. Use a 30° cutter to adjust the contact width of the top edge of the valve seat.

b

b Previous contact width

30˚ S69J5880

b Previous contact width

4. Use a 60° cutter to adjust the contact width of the bottom edge of the valve seat.

5-27

6D55F11

Cylinder head 7. If the valve seat contact area is too narrow and situated near the top edge of the valve face, use a 30° cutter to cut the top edge of the valve seat. If necessary, use a 45° cutter to center the area and set its width.

CAUTION: Do not get the lapping compound on the valve stem and valve guide.

10. After every lapping procedure, be sure to clean off any remaining lapping compound from the cylinder head and the valve.

11. Check the valve seat contact area of the valve again.

Checking the rocker arms and rocker arm shaft b Previous contact width

8. If the valve seat contact area is too narrow and situated near the bottom edge of the valve face, use a 60° cutter to cut the bottom edge of the valve seat. If necessary, use a 45° cutter to center the area and set its width.

b Previous contact width

9. Apply a thin, even layer of lapping compound onto the valve seat, and then lap the valve using a valve lapper (commercially available).

6D55F11

1. Check the rocker arms, rocker arm shaft, and rocker arm contact surface a for wear. Replace if necessary.

2. Measure the rocker arm inside diameter b and rocker arm shaft outside diameter c. Replace if out of specification.

Rocker arm inside diameter b: 16.000–16.018 mm (0.6299–0.6306 in) Rocker arm shaft outside diameter c: 15.971–15.991 mm (0.6288–0.6296 in)

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Checking the camshaft 1. Measure the cam lobe. Replace if out of specification.

Cam lobe a: Intake and exhaust: 30.834–31.034 mm (1.2139–1.2218 in) Cam lobe b: Intake and exhaust: 25.90–26.10 mm (1.0197–1.0276 in) 2. Measure the camshaft runout. Replace if above specification.

Camshaft journal diameter c: 36.925–36.945 mm (1.4537–1.4545 in) Camshaft journal diameter d: 36.935–36.955 mm (1.4541–1.4549 in) Cylinder head journal inside diameter e: 37.000–37.025 mm (1.4567–1.4577 in) 4. Calculate the camshaft journal oil clearance as follows. Replace the camshaft and cylinder head as a set if out of specification.

Camshaft journal oil clearance = Cylinder head journal inside diameter e – Camshaft journal diameter c, d: 0.050–0.090 mm (0.0020–0.0035 in)

Camshaft runout limit: 0.03 mm (0.0012 in)

5. Check the decompression actuator for damage or wear. Replace the camshaft if necessary.

Checking the cylinder head 3. Measure the camshaft journal diameters c and d, and cylinder head journal inside diameter e. Replace the camshaft and cylinder head if out of specification.

1. Eliminate carbon deposits from the combustion chambers and check for deterioration.

2. Check the cylinder head warpage using a straightedge 1 and thickness gauge 2 in six directions as shown. Replace if above specification.

5-29

6D55F11

Cylinder head

1 2

S6D55560

S6D55570

Cylinder head warpage limit: 0.10 mm (0.0039 in)

Checking the oil pump 1. Measure the oil pump rotor clearances as shown. Replace if out of specification.

Clearance a: 0.09–0.15 mm (0.0035–0.0059 in) Clearance b: Within 0.12 mm (0.047 in) Clearance c: 0.03–0.08 mm (0.0012–0.0031 in)

Installing the valves 1. Install a new valve seal 1 into the valve guide.

1

E

S62Y5590

6D55F11

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2. Install the valve 2, valve spring seat 3, valve spring 4, and valve spring retainer 5 in the sequence shown, and then attach the special service tool.

4. Lightly tap the valve spring retainer with a plastic hammer to set the valve cotter securely.

Installing the camshaft 1. Install a new oil seal 1.

1 NOTE: Face the fine pitch side a of the valve spring toward the spring seat.

Valve spring compressor 6: 90890-04019 Valve spring compressor attachment 7: 90890-06320

3

2

S6D55620

3. Compress the valve spring, and then install the valve cotter 8 using a thin screwdriver with a small amount of grease applied to it.

Bearing outer race attachment 2: 90890-06626 Driver rod LS 3: 90890-06606 2. Install the camshaft 4 in the direction shown, then the retaining bolt 5.

5-31

6D55F11

Cylinder head

M

S6D55660

T. R.

Rocker arm shaft bolt: 18 N·m (1.8 kgf·m, 13.3 ft·lb)

Installing the oil pump Installing the rocker arm shaft assembly 1. Assemble the rocker arm assemblies 1 and rocker arm shaft 2, and then install the tensioner 3, rocker arm retainers 4, and stopper guide 5 to the rocker arm shaft by installing the bolts 6.

1. Install the oil pump 1 by aligning the oil pump drive shaft a with the camshaft pin b.

c

1 S6D55670

NOTE: Make sure that the arrow marks a on the tensioner and stopper guide are facing up.

2. Install the rocker arm shaft assembly to the cylinder head by installing the bolts, and then tighten them to the specified torque.

6D55F11

NOTE: Before installing the oil pump, be sure to fill it with a small amount of engine oil through the oil passages c.

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Cylinder block

No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

5-33

Part name Oil filter Union bolt Exhaust cover Holder Bolt Thermostat cover Gasket Thermostat Gasket Bolt Engine hanger Filter Gasket Plug Gasket Cover Bolt

5

Q’ty 1 1 1 2 9 1 1 1 1 1 1 1 1 1 1 1 4

Remarks

M6 × 35 mm Not reusable Not reusable

M8 × 35 mm Steel Not reusable

Steel Not reusable

M6 × 20 mm

6D55F11

Cylinder block 5

No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

Part name Nut Balancer piston Cover O-ring Bolt Bolt Bolt Crankcase Main bearing Bolt Connecting rod assembly Connecting rod bearing Oil seal Balancer rod Crankshaft Oil seal Dowel

6D55F11

Q’ty 1 1 1 1 4 6 6 1 6 4 2 4 1 1 1 1 2

1 2 3 4 5 6 7 8 9

Remarks

Not reusable

M6 × 20 mm M8 × 82 mm M6 × 35 mm

Not reusable

Not reusable

5-34

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Power unit 5

No. 18 19 20 21 22

5-35

Part name Cylinder block Piston ring assembly Piston Piston pin Clip

Q’ty 1 2 2 2 4

Remarks

Not reusable

6D55F11

Cylinder block

Disassembling the cylinder block 1. Remove the thermostat cover and exhaust cover by removing the bolts in the sequence shown.

S6D55730

2. Remove the oil filter.

5. Remove the crankcase bolts in the sequence shown.

S6D55760

NOTE: Be sure to clean up any oil spills.

Oil filter wrench: 90890-01426 3. Remove the cover 1.

6. Remove the connecting rod bolts and the connecting rod caps, and then remove the connecting rod and piston assemblies.

7. Remove the crankshaft and oil seals.

4. Remove the nut 2, then the balancer piston 3.

6D55F11

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8. Remove the piston pin clips 4 and piston pin, and then remove the piston.

NOTE: • Be sure to keep the bearings in the order as they were removed.

• Mark each piston with an identification number a of the corresponding cylinder.

• Do not mix the connecting rods and caps.

Keep them organized in their proper groups.

Piston diameter a: 64.950–64.965 mm (2.5571–2.5577 in) Measuring point b: 2.0 mm (0.08 in) up from the bottom of the piston skirt Oversize piston diameter: Oversize 1st: 65.200–65.215 mm (2.5669–2.5675 in) Oversize 2nd: 65.450–65.465 mm (2.5768–2.5774 in)

Checking the cylinder bore 1. Measure the cylinder bore (D1–D6) at measuring points a, b, and c, and in direction d (D1, D3, D5), which is parallel to the crankshaft, and direction e (D2, D4, D6), which is at a right angle to the crankshaft.

Checking the balancer 1. Check the balancer piston for cracks or wear. Replace the balancer piston if necessary.

2. Check the balancer rod for cracks or wear. Replace the balancer rod if necessary.

c

b

a

D2

D1

d

D4

D3

e

D6

D5

Checking the piston diameter 1. Measure the piston outside diameter at the specified measuring point. Replace if out of specification.

S69J5B70

a 20 mm (0.8 in) b 40 mm (1.6 in) c 60 mm (2.4 in)

Cylinder bore (D1–D6): 65.000–65.015 mm (2.5590–2.5596 in) 2. Calculate the taper limit. Replace the cylinder block if above specification.

Taper limit: D1–D5 (direction d) D2–D6 (direction e) 0.08 mm (0.0032 in) 3. Calculate the out-of-round limit. Replace the cylinder block if above specification.

5-37

6D55F11

Cylinder block Out-of-round limit: D2–D1 (measuring point a) D6–D5 (measuring point c) 0.05 mm (0.0020 in)

3. Check the piston ring end gap d at the specified measuring point. Replace if out of specification.

Checking the piston clearance 1. Replace the piston and piston rings as a set or the cylinder block, or all parts if out of specification.

Piston clearance: 0.035–0.065 mm (0.0014–0.0026 in)

Checking the piston rings 1. Check the piston ring dimensions of B and T. Replace if out of specification.

Piston ring dimensions: Top ring a: B: 1.17–1.19 mm (0.0461–0.0469 in) T: 2.25–2.45 mm (0.0885–0.0965 in) 2nd ring b: B: 1.47–1.49 mm (0.0579–0.0587 in) T: 2.60–2.80 mm (0.1024–0.1102 in) Oil ring c: B: 2.36–2.48 mm (0.0929–0.0976 in) T: 2.75 mm (0.1083 in)

Piston ring end gap d: Top ring: 0.15–0.30 mm (0.0059–0.0118 in) 2nd ring: 0.30–0.50 mm (0.0118–0.0197 in) Oil ring: 0.20–0.70 mm (0.0079–0.0276 in) Measuring point e: 20 mm (0.8 in)

2. Level the piston ring 1 in the cylinder with a piston crown.

6D55F11

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Checking the piston ring grooves 1. Measure the piston ring grooves.

Replace the piston if out of specification.

Piston ring side clearance: Top ring a: 0.02–0.06 mm (0.0008–0.0024 in) 2nd ring b: 0.02–0.06 mm (0.0008–0.0024 in) Oil ring c: 0.04–0.18 mm (0.0016–0.0070 in)

Checking the piston pin boss bore 1. Measure the piston pin boss bore.

Replace the piston if out of specification.

Piston ring groove: Top ring a: 1.21–1.23 mm (0.0476–0.0484 in) 2nd ring b: 1.51–1.53 mm (0.0594–0.0602 in) Oil ring c: 2.52–2.54 mm (0.0992–0.1000 in)

Checking the piston ring side clearance 1. Measure the piston ring side clearance.

Replace the piston and piston rings as a set if out of specification.

Piston pin boss bore: 15.974–15.985 mm (0.6289–0.6293 in)

Checking the piston pin 1. Measure the piston pin diameter.

Replace if out of specification.

Piston pin diameter: 15.965–15.970 mm (0.6285–0.6287 in)

5-39

6D55F11

Cylinder block

Checking the connecting rod small end inside diameter 1. Measure the connecting rod small end inside diameter a. Replace the connecting rod if out of specification.

a S6D55810

b

Connecting rod small end inside diameter a: 15.985–15.998 mm (0.6293–0.6298 in)

Checking the connecting rod big end side clearance 1. Measure the connecting rod big end side clearance a. Replace the connecting rod or crankshaft, or both if out of specification.

c S6D55820

Crankshaft journal diameter a: 42.984–43.000 mm (1.6923–1.6929 in) Crankpin diameter b: 32.984–33.000 mm (1.2986–1.2992 in) Crankpin width c: 21.000–21.070 mm (0.8268–0.8295 in)

a 2. Measure the crankshaft runout. Replace the crankshaft if above specification.

a

S6D55800

Connecting rod big end side clearance a: 0.05–0.22 mm (0.0020–0.0087 in) S6D55830

Checking the crankshaft 1. Measure the crankshaft journal diameter a, crankpin diameter b, and crankpin width c. Replace the crankshaft if out of specification.

6D55F11

Crankshaft runout limit: 0.05 mm (0.0020 in)

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Checking the crankpin oil clearance 1. Clean the bearings and the connecting rod.

2. Install the upper bearing into the connecting rod 1 and the lower bearing into the connecting rod cap 2.

NOTE: • Install the connecting rod bearings in their original positions.

• Insert the projection a of each bearing into the slots in the connecting rod cap and connecting rod.

3. Put a piece of Plastigauge (PG-1) onto the crankpin, parallel to the crankshaft.

NOTE: Be sure not to put the Plastigauge (PG-1) over the oil hole in the crankpin of the crankshaft.

NOTE: Do not turn the connecting rod until the crankpin oil clearance measurement has been completed.

R.

5-41

5. Tighten the connecting rod bolts to the specified torques in two stages.

T.

4. Install the connecting rod to the crankpin 3.

NOTE: Make sure that the marks b of the connecting rod faces towards the flywheel magnet side of the crankshaft.

Connecting rod bolt: 1st: 6 N·m (0.6 kgf·m, 4.4 ft·lb) 2nd: 17 N·m (1.7 kgf·m, 12.5 ft·lb)

6D55F11

Cylinder block 6. Remove the connecting rod cap and measure the width of the compressed Plastigauge (PG-1) on each crankpin.

Replace the connecting rod bearing if out of specification.

Connecting rod mark a

Bearing color b

A

Blue

B

Black

C

Brown

Checking the crankshaft main journal oil clearance 1. Clean the bearings, main journals, and bearing portions of the crankcase and cylinder block.

2. Place the cylinder block upside down on a bench.

Crankpin oil clearance: 0.020–0.052 mm (0.0008–0.0020 in)

3. Install half of the bearings 1 and the crankshaft 2 into the cylinder block 3.

Selecting the connecting rod bearing 1. When replacing the connecting rod bearing, select the suitable bearing as follows.

2. Check the connecting rod mark a.

NOTE: • Install the main bearings in their original positions.

• Insert the projection a of each bearing into the slots in the cylinder block.

3. Select the suitable color b for the connecting rod bearing from the table.

6D55F11

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4. Put a piece of Plastigauge (PG-1) on each main journal parallel to the crankshaft.

NOTE: Do not put the Plastigauge (PG-1) over the oil hole in the main journals of the crankshaft.

Crankshaft main journal oil clearance: 0.012–0.044 mm (0.0005–0.0017 in)

Selecting the crankshaft main bearing

5. Install the remaining half of the bearings into the crankcase.

1. When replacing the main bearing, select the suitable bearing as follows.

NOTE: • Install the main bearings in their original positions.

• Insert the projection of each bearing into the slots in the crankcase.

2. Check the cylinder block mark a on the cylinder block.

3. Select the suitable color b for the main bearing from the table.

6. Install the crankcase onto the cylinder block.

7. Apply engine oil to the threads of the crankcase bolts and tighten them to the specified torques in two stages.

T. R.

Crankcase bolt (M8): 1st: 15 N·m (1.5 kgf·m, 11.1 ft·lb) 2nd: 30 N·m (3.0 kgf·m, 22.1 ft·lb) Crankcase bolt (M6): 1st: 6 N·m (0.6 kgf·m, 4.4 ft·lb) 2nd: 12 N·m (1.2 kgf·m, 8.9 ft·lb)

8. Remove the crankcase, and then measure the width of the compressed Plastigauge (PG-1) on each main journal.

Replace the main bearing if out of specification.

5-43

Cylinder block mark a

Bearing color b

A

Blue

B

Black

C

Brown

6D55F11

Cylinder block

Assembling the pistons and cylinder block

d #3

1. Assemble the piston 1, connecting rod 2, piston pin 3, and piston pin clips 4.

45˚

45˚

#2

UP

T UP 63P

5 #1,#4

#5

#5

#4

6

#3 #2

#1

E

7

T

d S6D55900

CAUTION: Do not scratch the pistons or break the piston rings.

NOTE: After installing the piston rings, check that they move smoothly.

NOTE: • Face the embossed “Y” mark a on the connecting rod in the same direction as the “UP” mark b on the piston.

• Always use new piston pin clips, and do not allow the piston pin clip end to align with the piston pin slot c.

4. Install the upper bearing into the connecting rod and the lower bearing into the connecting rod cap 8.

2. Install the oil ring 5, second ring 6, and top ring 7 onto each piston with the “T” marks d of the second ring and the top ring facing upward.

3. Offset the piston ring end gaps as shown.

6D55F11

NOTE: • Install the connecting rod bearings in their original positions.

• Insert the projection e of each bearing into the slots in the connecting rod cap and connecting rod.

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5. Install the piston with the “UP” mark on the piston crown facing towards the flywheel magnet.

NOTE: Apply engine oil to the side of the pistons and piston rings before installation.

Piston slider: 90890-06529 6. Install half of the main bearings 9 into the cylinder block 0.

NOTE: Apply engine oil to the inner oil seals before installation.

9. Install the connecting rod caps D to the connecting rods, and then tighten the connecting rod bolts to the specified torques in two stages.

0

9

D

E

f

S6D55920

NOTE: • Install the main bearings in their original positions.

• Insert the projection f of each bearing into the slots in the cylinder block.

7. Install the balancer rod onto the crankshaft.

S6D55950

NOTE: • Align the alignment marks g on the connecting rod cap and connecting rod.

• Apply engine oil to the connecting rod bolts before installation.

8. Set the crankshaft A and oil seals B and C into the cylinder block as shown.

T. R.

5-45

E

g

Connecting rod bolt: 1st: 6 N·m (0.6 kgf·m, 4.4 ft·lb) 2nd: 17 N·m (1.7 kgf·m, 12.5 ft·lb)

6D55F11

Cylinder block 10. Install half of the main bearings into the crankcase.

T. R.

NOTE: • Install the main bearings in their original positions.

• Insert the projection of each bearing into the slots in the crankcase.

11. Apply sealant to the mating surface of the crankcase.

1–6 Crankcase bolt (M8): 1st: 15 N·m (1.5 kgf·m, 11.1 ft·lb) 2nd: 30 N·m (3.0 kgf·m, 22.1 ft·lb) 7–B Crankcase bolt (M6): 1st: 6 N·m (0.6 kgf·m, 4.4 ft·lb) 2nd: 12 N·m (1.2 kgf·m, 8.9 ft·lb)

14. Install the balancer piston E into the crankcase, and then tighten the balancer piston nut F to the specified torque.

15. Install a new O-ring and the balancer cover G, and then tighten the bolts H to the specified torque.

NOTE: Do not get any sealant on the main bearings.

12. Install the crankcase onto the cylinder block.

13. Tighten the crankcase bolts to the specified torques in two stages and in the sequence shown.

NOTE: Apply engine oil to the balancer piston nut and balancer cover bolts before installation.

E T. R.

Balancer piston nut F: 157 N·m (15.7 kgf·m, 115.8 ft·lb) Balancer cover bolt H: 12 N·m (1.2 kgf·m, 8.9 ft·lb)

S6D55970

NOTE: Apply engine oil to the crankcase bolts before installation.

6D55F11

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Power unit

16. Before installing the oil filter, be sure to supply engine oil to the oil passage h.

h

S6D55A10

S6D55990 T. R.

17. Install the oil filter, and then tighten it to the specified torque using the oil filter wrench.

Exhaust cover bolt: 1st: 6 N·m (0.6 kgf·m, 4.4 ft·lb) 2nd: 12 N·m (1.2 kgf·m, 8.9 ft·lb) Thermostat cover bolt: 7 N·m (0.7 kgf·m, 5.2 ft·lb)

Installing the cylinder head 1. Install a new gasket and the cylinder head, and then tighten the bolts to the specified torques in the sequence shown.

$ # NOTE: Apply a thin coat of engine oil to the O-ring of the new oil filter before installation.

²!

±(

E

%

& S6D55690

Oil filter wrench: 90890-01426

CAUTION: T. R.

Oil filter: 18 N·m (1.8 kgf·m, 13.3 ft·lb)

18. Install a new gasket and the exhaust cover.

19. Install the thermostat and thermostat cover, and then tighten the bolts to the specified torques in two stages and in the sequence shown.

5-47

Do not reuse the cylinder head gasket, always replace it with a new one.

NOTE: • Apply engine oil to the cylinder head bolts before installation.

• Tighten the bolts to the specified torques in two stages.

6D55F11

Cylinder block

T. R.

Cylinder head bolt (M9): 1st: 23 N·m (2.3 kgf·m, 17.0 ft·lb) 2nd: 46 N·m (4.6 kgf·m, 34.0 ft·lb) Cylinder head bolt (M6): 1st: 6 N·m (0.6 kgf·m, 4.4 ft·lb) 2nd: 12 N·m (1.2 kgf·m, 8.9 ft·lb)

2. Install the cylinder head cover, and then tighten the bolts.

3. Install the driven sprocket 1, and then tighten the bolt to the specified torque.

6. Install the timing belt 3 to the drive sprocket and then to the driven sprocket with its part number in the upright position.

3

Flywheel holder: 90890-06522

T. R.

Driven sprocket bolt: 38 N·m (3.8 kgf·m, 28.0 ft·lb)

S6D55150

CAUTION: 4. Check that “ ” mark a on the driven sprocket is aligned with the “ ” mark b on the cylinder head. Align if necessary.

Do not to damage the timing belt during installation.

NOTE: When installing the timing belt, lift the drive sprocket slightly to ease installation. Be careful the Woodruff key for the drive sprocket does not slide out of position.

5. Install the drive sprocket 2, and then check that the mark c on the drive sprocket is aligned with the mark d on the cylinder block. Align if necessary.

6D55F11

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7. Adjust the valve clearance.

Valve clearance: Intake: 0.15–0.25 mm (0.006–0.010 in) Exhaust: 0.25–0.35 mm (0.010–0.014 in)

6. Connect the blowby hose 7.

7

NOTE: For adjustment procedures, see “Checking the valve clearance”.

Installing the power unit 1. Clean the power unit mating surface, and install the dowels 1 and a new gasket 2.

S6D55A50

7. Connect the throttle cable 8 and shift cable 9 (remote control model), or throttle cables 0 (tiller handle model), and then adjust their lengths. For adjustment procedures, see Chapter 3.

2. Install the power unit 3 by installing the bolts 4, then tightening them to the specified torque.

3. Install the apron 5 by installing the bolts 6, then tightening them to the specified torque.

9

8 S6D55A60

0

S6D55A70

8. Install the stator coil.

T. R.

Power unit mounting bolt 4: 21 N·m (2.1 kgf·m, 15.5 ft·lb) Apron bolt 6: 10 N·m (1.0 kgf·m, 7.4 ft·lb)

9. Install the Woodruff key.

4. Connect the engine stop lanyard switch leads, cooling water pilot hose, and fuel hose.

5. Install the dipstick.

5-49

6D55F11

Cylinder block 10. Install the flywheel magnet.

12. Install all parts removed during disassembly.

1 2 3 4 5 6 7 8 9

CAUTION: Apply force in the direction of the arrows shown to prevent the flywheel holder from slipping off easily.

NOTE: Apply engine oil to the flywheel magnet nut before installation.

Flywheel holder: 90890-06522

T. R.

Flywheel magnet nut: 157 N·m (15.7 kgf·m, 115.8 ft·lb)

11. Install the starter pulley, and then tighten the bolts to the specified torque.

Universal clutch holder: 90890-04086

T. R.

Starter pulley bolt: 25 N·m (2.5 kgf·m, 18.4 ft·lb)

6D55F11

5-50

POWR

Power unit

— MEMO —

5-51

6D55F11

LOWR

Lower unit Special service tools .....................................................................................6-1 Lower unit ....................................................................................................... 6-4 Removing the lower unit ............................................................................6-7 Removing the water pump......................................................................... 6-7 Checking the water pump..........................................................................6-8 Propeller shaft housing ................................................................................. 6-9 Removing the propeller shaft housing assembly..................................... 6-11 Disassembling the propeller shaft assembly ...........................................6-11 Disassembling the propeller shaft housing.............................................. 6-11 Disassembling the oil seal housing ......................................................... 6-12 Checking the propeller shaft housing ......................................................6-12 Checking the propeller shaft and shift rod ............................................... 6-12 Assembling the propeller shaft assembly ................................................ 6-12 Assembling the propeller shaft housing...................................................6-13 Assembling the oil seal housing ..............................................................6-14 Drive shaft and lower case..........................................................................6-15 Removing the drive shaft.........................................................................6-16 Disassembling the drive shaft.................................................................. 6-16 Disassembling the forward gear ..............................................................6-16 Disassembling the lower case .................................................................6-16 Checking the pinion and forward gear.....................................................6-17 Checking the bearings............................................................................. 6-17 Checking the drive shaft ..........................................................................6-17 Checking the lower case .........................................................................6-17 Assembling the lower case...................................................................... 6-17 Assembling the forward gear................................................................... 6-18 Assembling the drive shaft ...................................................................... 6-18 Installing the pinion.................................................................................. 6-19 Installing the propeller shaft housing .......................................................6-19 Installing the water pump and shift rod....................................................6-19 Installing the lower unit ............................................................................6-21 Shimming...................................................................................................... 6-23 Shimming.................................................................................................6-24 Selecting the pinion shims....................................................................... 6-24 Selecting the forward gear shims ............................................................ 6-25 Selecting the reverse gear shims ............................................................ 6-26 Backlash ....................................................................................................... 6-27 Measuring the forward and reverse gear backlash .................................6-27

6D55F11

1 2 3 4 5 6 7 8 9

LOWR

Lower unit

Special service tools

6

Bearing housing puller claw S 90890-06564

Bearing puller assembly 90890-06535

Stopper guide plate 90890-06501

Needle bearing attachment 90890-06608, 90890-06611, 90890-06615

Center bolt 90890-06504

Driver rod L3 90890-06652

Bearing separator 90890-06534

Ball bearing attachment 90890-06635, 90890-06637

Stopper guide stand 90890-06538

Driver rod LS 90890-06606

6-1

6D55F11

Special service tools

Driver rod SS 90890-06604

Bearing outer race attachment 90890-06625, 90890-06628

Bearing depth plate 90890-06603

Driver rod LL 90890-06605

Bearing inner race attachment 90890-06640, 90890-06643, 90890-06644

Pinion height gauge 90890-06710

Drive shaft holder 3 90890-06517

Pinion height gauge plate B 90890-06712

Driver rod SL 90890-06602

Digital caliper 90890-06704

6D55F11

1 2 3 4 5 6 7 8 9 6-2

LOWR

Lower unit

Shimming plate 90890-06701

Backlash indicator 90890-06706

Magnet base plate 90890-07003

Dial gauge set 90890-01252

Magnet base B 90890-06844

6-3

6D55F11

Special service tools / Lower unit

Lower unit

No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

Part name Lower unit Check screw Gasket Drain screw Adjusting nut Locknut Cooling water inlet cover Nut Bolt Washer Anode Screw Bolt Bolt Trim tab Spacer Propeller

6D55F11

6

Q’ty 1 1 2 1 1 1 2 2 1 1 1 2 4 1 1 1 1

1 2 3 4 5 6 7 8 9

Remarks

Not reusable

M6 × 35 mm

ø5 × 26 mm M10 × 35 mm M6 × 20 mm

6-4

LOWR

Lower unit 6

No. 18 19 20 21 22

6-5

Part name Collar Washer Nut Cotter pin Dowel

Q’ty 1 1 1 1 2

Remarks

Not reusable

6D55F11

Lower unit 6

No. 1 2

Part name Water tube O-ring

Q’ty 1 2

1 2 3 4 5 6 7 8 9

Remarks L-transom model Not reusable

L-transom model 3 4 5 6 7 8 9 10 11 12 13 14

O-ring Water tube O-ring Bolt Extension plate Cover Water pump housing Insert cartridge O-ring Impeller Outer plate cartridge Woodruff key

6D55F11

1 1 1 4 1 1 1 1 1 1 1 1

Not reusable

S-transom model S-transom model Not reusable

S-transom model M6 × 40 mm

Not reusable

6-6

LOWR

Lower unit

Removing the lower unit 1. Drain the gear oil.

4. Loosen the locknut 3, and then remove the adjusting nut 4.

5. Loosen the bolts 5, and then remove the lower unit from the upper case.

2. Shift the remote control lever or shift lever to neutral, place a block of wood between the anti-cavitation plate and propeller to keep the propeller from turning, and then remove the propeller nut and propeller.

Removing the water pump 1. Remove the water pump assembly.

WARNING • Do not hold the propeller with your hands when loosening or tightening it.

• Be sure to remove the clip from the engine stop lanyard switch.

• Put a block of wood between the anticavitation plate and propeller to keep the propeller from turning.

3. Remove the anode 1 and trim tab 2.

NOTE: Note the trim tab position.

6-7

È S-transom model É L-transom model

6D55F11

Lower unit

Checking the water pump 1. Check the water pump housing for deformation. Replace if necessary.

1 2 3 4 5 6 7 8 9

2. Check the impeller and insert cartridge for cracks or wear. Replace if necessary.

3. Check the Woodruff key 1 and the keyway a in the drive shaft for wear.

Replace if necessary.

a

1

S6D56050

6D55F11

6-8

LOWR

Lower unit

Propeller shaft housing

No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

6-9

Part name Shift plunger Dog clutch Cross pin Spring Spring Propeller shaft Washer Reverse gear Reverse gear shim O-ring Ball bearing O-ring Propeller shaft housing Needle bearing Oil seal Oil seal Water seal

6

Q’ty 1 1 1 1 1 1 1 1 — 1 1 2 1 1 2 2 1

Remarks

Not reusable Not reusable Not reusable

Not reusable Not reusable

6D55F11

Propeller shaft housing 6

No. 18 19 20 21 22 23 24 25

Part name Bolt Shift rod bracket Shift rod plate O-ring Oil seal housing Dowel Gasket Shift rod

6D55F11

Q’ty 2 1 1 1 1 3 1 1

1 2 3 4 5 6 7 8 9

Remarks M6 × 25 mm

Not reusable

Not reusable

6-10

LOWR

Lower unit

Removing the propeller shaft housing assembly 1. Remove the bolts, and then pull out the propeller shaft housing assembly.

Bearing housing puller claw S 1: 90890-06564 Stopper guide plate 2: 90890-06501 Center bolt 3: 90890-06504

Disassembling the propeller shaft assembly 1. Remove the spring 1, then the cross pin 2, dog clutch 3, shift plunger 4, and spring 5.

Bearing separator 1: 90890-06534 Stopper guide plate 2: 90890-06501 Stopper guide stand 3: 90890-06538 Bearing puller assembly 4: 90890-06535 2. Remove the ball bearing.

CAUTION:

Disassembling the propeller shaft housing 1. Remove the reverse gear and reverse gear shim(s).

Do not reuse the bearing, always replace it with a new one.

Stopper guide plate 5: 90890-06501 Stopper guide stand 6: 90890-06538 Bearing puller assembly 7: 90890-06535 3. Remove the oil seals and needle bearing.

6-11

6D55F11

Propeller shaft housing 2. Check the propeller shaft for bends or wear. Replace if necessary.

3. Measure the propeller shaft runout.

Needle bearing attachment 8: 90890-06615 Driver rod L3 9: 90890-06652

Disassembling the oil seal housing

S6D56510

Runout limit: 0.02 mm (0.0008 in)

1. Remove the oil seals.

4. Check the dog clutch and shift plunger for cracks or wear. Replace if necessary.

Assembling the propeller shaft assembly 1. Install the dog clutch as shown.

Ball bearing attachment 1: 90890-06637 Driver rod LS 2: 90890-06606

Checking the propeller shaft housing 1. Clean the propeller shaft housing using a soft brush and cleaning solvent, and then check it for cracks. Replace if necessary.

2. Check the teeth and dogs of the reverse gear for cracks or wear. Replace the gear if necessary.

NOTE: Install the dog clutch 1 with the “F” mark a facing toward the shift plunger.

3. Check the bearings for pitting or rumbling. Replace if necessary.

Checking the propeller shaft and shift rod 1. Check the shift rod cracks or wear.

Replace if necessary.

6D55F11

6-12

1 2 3 4 5 6 7 8 9

LOWR

Lower unit

Assembling the propeller shaft housing 1. Install the needle bearing into the propeller shaft housing to the specified depth.

Needle bearing attachment 4: 90890-06611 Driver rod L3 5: 90890-06652 Depth d: 13.0–13.5 mm (0.512–0.532 in) Depth e: 6.0–6.5 mm (0.236–0.256 in) 3. Install the original shim(s) 6 and new ball bearing 7 onto the reverse gear 8 using a press.

NOTE: • Install the needle bearing with the manufacture identification mark a facing toward the reverse gear.

• When using the driver rod, do not strike the special service tool in a manner that will force the stopper c out of place.

Driver rod SS 1: 90890-06604 Needle bearing attachment 2: 90890-06615 Bearing depth plate 3: 90890-06603 Depth b: 31.0–31.5 mm (1.22–1.24 in) 2. Apply grease to new oil seals, and then install them into the propeller shaft housing to the specified depth.

CAUTION: Add or remove shim(s), if necessary, if replacing the reverse gear, ball bearing, propeller shaft housing, or lower case.

NOTE: Install the ball bearing with the manufacturer identification mark f facing inward (reverse gear side).

Bearing inner race attachment 9: 90890-06640 4. Install the reverse gear assembly into the propeller shaft housing using a press.

NOTE: Install an oil seal halfway into the propeller shaft housing, then the other oil seal.

6-13

6D55F11

Propeller shaft housing

1 2 3 4 5 6 7 8 9

Needle bearing attachment 0: 90890-06608

Assembling the oil seal housing 1. Apply grease to new oil seals, and then install them into the oil seal housing to the specified depth.

Ball bearing attachment 1: 90890-06635 Driver rod LS 2: 90890-06606 Depth a: 5.5–6.0 mm (0.217–0.236 in)

6D55F11

6-14

LOWR

Lower unit

Drive shaft and lower case

No. 1 2 3 4 5 6 7 8 9 10 11

6-15

Part name Drive shaft Taper roller bearing assembly Pinion shim Sleeve Needle bearing Pinion Nut Forward gear shim Taper roller bearing assembly Forward gear Lower case

6

Q’ty 1 1 — 1 1 1 1 — 1 1 1

Remarks Not reusable

Not reusable

6D55F11

Drive shaft and lower case

Removing the drive shaft 1. Remove the drive shaft assembly and pinion, and then pull out the forward gear.

1

CAUTION: S68S6150

Drive shaft holder 3 1: 90890-06517

Disassembling the drive shaft 1. Install the pinion nut 1, tighten it finger tight, and then remove the drive shaft bearing 2 using a press.

CAUTION: • Do not press the drive shaft threads a directly.

• Do not reuse the bearing, always replace it with a new one.

Do not reuse the bearing, always replace it with a new one.

Bearing separator 1: 90890-06534

Disassembling the lower case 1. Remove the taper roller bearing outer race and shim(s).

NOTE: Install the claws as shown.

Bearing puller assembly 1: 90890-06535 Stopper guide plate 2: 90890-06501

Bearing inner race attachment 3: 90890-06643

Disassembling the forward gear 1. Remove the taper roller bearing from the forward gear using a press.

6D55F11

6-16

1 2 3 4 5 6 7 8 9

LOWR

Lower unit

2. Remove the drive shaft bearing outer race, shim(s), and drive shaft sleeve.

Checking the drive shaft 1. Check the drive shaft for bends or wear.

Replace if necessary.

2. Measure the drive shaft runout.

NOTE: Install the claws as shown.

Stopper guide plate 3: 90890-06501 Stopper guide stand 4: 90890-06538 Bearing puller assembly 5: 90890-06535 3. Remove the needle bearing.

S6D56520

Runout limit: 0.5 mm (0.020 in)

Checking the lower case 1. Check the skeg and torpedo for cracks or damage. Replace the lower case if necessary.

Assembling the lower case 1. Install the needle bearing into the lower case to the specified depth.

Needle bearing attachment 6: 90890-06615 Driver rod L3 7: 90890-06652

Checking the pinion and forward gear 1. Check the teeth of the pinion, and the teeth and dogs of the forward gear for cracks or wear. Replace if necessary.

Checking the bearings 1. Check the bearings for pitting or rumbling. Replace if necessary.

6-17

NOTE: • Install the needle bearing with the manufacture identification mark a facing up.

• When using the driver rod, do not strike the special service tool in a manner that will force the stopper b out of place.

Driver rod SL 1: 90890-06602 Needle bearing attachment 2: 90890-06615 Bearing depth plate 3: 90890-06603

6D55F11

Drive shaft and lower case Depth c: 185–186 mm (7.283–7.323 in) 2. Install the sleeve, original shim(s), and drive shaft bearing outer race.

CAUTION: Add or remove shim(s), if necessary, if replacing the forward gear or lower case.

Bearing outer race attachment 6: 90890-06625 Driver rod LL 7: 90890-06605

Assembling the forward gear 1. Install a new taper roller bearing into the forward gear using a press.

CAUTION: Add or remove shim(s), if necessary, if replacing the pinion or lower case.

NOTE: • Apply gear oil to the inside and outside of the sleeve before installation.

• Install the sleeve with the projection d facing forward.

Bearing inner race attachment 1: 90890-06644

Assembling the drive shaft 1. Install a new drive shaft bearing onto the drive shaft using a press.

Bearing outer race attachment 4: 90890-06628 Driver rod LS 5: 90890-06606 3. Install the original shim(s) and taper roller bearing outer race.

Bearing inner race attachment 1: 90890-06643

6D55F11

6-18

1 2 3 4 5 6 7 8 9

LOWR

Lower unit

Installing the pinion 1. Install the forward gear, then the drive shaft assembly, pinion, and pinion nut, and then tighten the nut to the specified torque.

LT

5

572

4

1 G

S6D56260

T. R.

S68S6410

Drive shaft holder 3 1: 90890-06517

T. R.

Pinion nut: 50 N·m (5.0 kgf·m, 36.9 ft·lb)

Propeller shaft housing bolt: 11 N·m (1.1 kgf·m, 8.1 ft·lb)

Installing the water pump and shift rod 1. Install the shift rod 1, new gasket 2, and oil seal housing 3.

2. Install the shift rod plate 4, and shift rod bracket 5, and then tighten the bolts 6.

Installing the propeller shaft housing 1. Install the washer 1 and propeller shaft assembly 2 into the propeller shaft housing assembly 3.

2. Apply grease to the new O-rings.

3. Install the outer plate cartridge, and then install the woodruff key into the drive shaft.

3. Install the propeller shaft housing assembly 4 into the lower case, and then tighten the bolts 5 to the specified torque.

6-19

4. Align the groove in the impeller 7 with the Woodruff key 8, and then install the impeller onto the drive shaft.

6D55F11

Drive shaft and lower case

C A

c d

B 5. Install the new O-ring 9 and insert cartridge 0 into the pump housing A, and then apply grease to the inside of the insert cartridge.

9

0 S6D56300

b A a A S6D56290

NOTE: Align the insert cartridge projection a with the hole b in the pump housing.

NOTE: • When installing the pump housing, apply grease to the inside of the housing, and then turn the drive shaft clockwise while pushing down the pump housing.

• Align the cover projection c with the hole d in the pump housing.

7. Install the extension plate D, and then tighten the bolts E.

6. Install the pump housing assembly B into the lower case, and then install the cover C.

È S-transom model É L-transom model

6D55F11

6-20

1 2 3 4 5 6 7 8 9

LOWR

Lower unit

Installing the lower unit 1. Set the remote control lever or shift lever to reverse. È

5. Install the trim tab 5 to its original position, and then tighten the trim tab bolt 6.

R N

S6D56310

É

N F

R

T. R.

S6D56320

Lower case mounting bolt 2: 37 N·m (3.7 kgf·m, 27.3 ft·lb)

È Tiller handle model É Remote control model

Length a: 8–9 mm (0.31–0.35 in) 6. Install the propeller and propeller nut, and then tighten the nut finger tight.

Place a block of wood between the anticavitation plate and propeller to keep the propeller from turning, and then tighten the nut to the specified torque.

2. Install the two dowels 1 into the lower unit.

3. Install the lower unit into the upper case, and then tighten the lower case mounting bolts 2 to the specified torque.

4. Turn the adjusting nut 3 to the specified length a, and then tighten the locknut 4.

6-21

6D55F11

Drive shaft and lower case 8. Install the check screw and quickly install the drain screw.

1 2 3 4 5 6 7 8 9

WARNING • Do not hold the propeller with your hands when loosening or tightening it.

• Be sure to remove the clip from the engine stop lanyard switch.

• Put a block of wood between the anticavitation plate and propeller to keep the propeller from turning.

NOTE: If the grooves in the propeller nut 7 do not align with the cotter pin hole, tighten the nut until they are aligned.

T. R.

Propeller nut 7: 34 N·m (3.4 kgf·m, 25.1 ft·lb)

7. Insert a gear oil tube or gear oil pump into the drain hole and slowly fill the gear oil until oil flows out of the check hole and no air bubbles are visible.

Recommended gear oil: Hypoid gear oil SAE: 90 Oil quantity: 320 cm3 (10.8 US oz, 11.3 Imp oz)

6D55F11

6-22

LOWR

Lower unit

Shimming

6

T3

B3 A3

42.5

T1

T2 24.0 24.0 B1 A1

B2 A2 S6D56370

6-23

6D55F11

Shimming

Shimming

T. R.

NOTE: • Shimming is not required when assembling the original lower case and inner parts.

• Shimming is required when assembling the original inner parts and a new lower case.

• Shimming is required when replacing the inner part(s).

2. Install the pinion and pinion nut, and then tighten the nut to the specified torque.

Pinion nut: 50 N·m (5.0 kgf·m, 36.9 ft·lb)

3. Measure the distance (M3) between the special service tool and the pinion as shown.

Selecting the pinion shims 1. Install the special service tools onto the drive shaft 1.

Digital caliper 4: 90890-06704

NOTE: • Select the shim thickness (T3) by using the specified measurement(s) and the calculation formula.

• Install the special service tool onto the drive shaft so that the shaft is at the center of the hole.

• Tighten the wing nuts another 1/4 of a turn after they contact the plate 2.

Pinion height gauge plate B 2: 90890-06712 Pinion height gauge 3: 90890-06710

6D55F11

6-24

1 2 3 4 5 6 7 8 9

LOWR

Lower unit

4. Calculate the pinion shim thickness (T3) as shown in the examples below.

+5 -1

Example: If “T3” is 1.25 mm, then the pinion shim is 1.3 mm.

If “T3” is 1.75 mm, then the pinion shims are 0.7 and 1.1 mm.

+5

a

Selecting the forward gear shims 1. Turn the taper roller bearing outer race 1 two or three times to seat the rollers, and then measure the bearing height (M1) as shown.

S6D56390

NOTE: “P” is the deviation of the lower case dimension from standard. The “P” mark a is stamped on the anode mounting surface of the lower case in 0.01 mm units. If the “P” mark is unreadable, assume that “P” is zero and check the backlash when the unit is assembled.

Calculation formula: Pinion shim thickness (T3) = M3 – 27.00 – P/100 Example: If “M3” is 28.30 mm and “P” is (+5), then T3 = 28.30 – 27.00 – (+5)/100 mm = 1.3 – 0.05 mm = 1.25 mm 5. Select the pinion shim(s) (T3) as follows.

Calculated numeral More than

Up to

Shim size to use

1.10

1.20

1.2

1.20

1.30

1.3

1.30

1.40

1.4

1.40

1.50

1.5

1.50

1.60

1.6

1.60

1.70

0.7 + 1.0

1.70

1.83

0.7 + 1.1

NOTE: • Select the shim thickness (T1) by using the specified measurement(s) and the calculation formula.

• Measure the bearing outer race at three points to find the height average.

Shimming plate 2: 90890-06701 Digital caliper 3: 90890-06704 2. Calculate the forward gear shim thickness (T1) as shown in the examples below.

Available shim thicknesses: 0.7, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, and 1.6 mm

6-25

6D55F11

Shimming

Selecting the reverse gear shims a +5 -1

1. Install the ball bearing onto the propeller shaft housing.

+5

2. Measure the bearing housing height (M2) as shown.

S6D56400

NOTE: “F” is the deviation of the lower case dimension from standard. The “F” mark a is stamped on the anode mounting surface of the lower case in 0.01 mm units. If the “F” mark is unreadable, assume that “F” is zero and check the backlash when the unit is assembled.

Calculation formula: Forward gear shim thickness (T1) = 17.50 + F/100 – M1 Example: If “M1” is 16.25 mm and “F” is (+5), then T1 = 17.50 + (+5)/100 – 16.25 mm = 17.50 + 0.05 – 16.25 mm = 1.30 mm 3. Select the forward gear shim(s) (T1) as follows.

Calculated numeral More than

Up to

Shim size to use

0.99

1.10

1.0

1.10

1.20

1.1

1.20

1.30

1.2

1.30

1.40

1.3

1.40

1.50

1.4

NOTE: • Select the shim thickness (T2) by using the specified measurement(s) and the calculation formula.

• Measure the bearing housing at three points to find the height average.

Shimming plate 1: 90890-06701 Digital caliper 2: 90890-06704

Available shim thicknesses: 1.0, 1.1, 1.2, 1.3, and 1.4 mm Example: If “T1” is 1.15 mm, then the forward gear shim is 1.1 mm.

If “T1” is 1.30 mm, then the forward gear shim is 1.2 mm.

6D55F11

6-26

1 2 3 4 5 6 7 8 9

LOWR

Lower unit

3. Calculate the reverse gear shim thickness (T2) as shown in the examples below.

a +5 -1

Example: If “T2” is 1.05 mm, then the reverse gear shim is 1.0 mm.

If “T2” is 1.20 mm, then the reverse gear shim is 1.1 mm.

Backlash

+5

6

Measuring the forward and reverse gear backlash 1. Remove the water pump assembly.

S6D56430

NOTE: “R” is the deviation of the lower case dimension from standard. The “R” mark a is stamped on the anode mounting surface of the lower case in 0.01 mm units. If the “R” mark is unreadable, assume that “R” is zero and check the backlash when the unit is assembled.

2. Set the gear shift to the neutral position at the lower unit.

3. Install the special service tools so that it pushes against the propeller shaft.

Calculation formula: Reverse gear shim thickness (T2) = 80.00 + R/100 – M2 Example: If “M2” is 78.79 mm and “R” is (–1), then T2 = 80.00 + (–1)/100 – 78.79 mm = 80.00 – 0.01 – 78.79 mm = 1.20 mm 4. Select the reverse gear shim(s) (T2) as follows.

Calculated numeral More than

Up to

Shim size to use

0.99

1.10

1.0

1.10

1.20

1.1

1.20

1.30

1.2

1.30

1.32

1.3

NOTE: Tighten the center bolt while turning the drive shaft until the drive shaft can no longer be turned.

Bearing housing puller claw S 1: 90890-06564 Stopper guide plate 2: 90890-06501 Center bolt 3: 90890-06504 4. Install the backlash indicator onto the drive shaft (16.0 mm [0.63 in] in diameter), then the dial gauge onto the lower unit.

Available shim thicknesses: 1.0, 1.1, 1.2, and 1.3 mm

6-27

6D55F11

Shimming / Backlash 7. Remove the special service tools from the propeller shaft.

8. Apply a load to the reverse gear by installing the propeller 8 (without the spacer 9), the collar 0, then the washer A as shown.

NOTE: Install the dial gauge so that the plunger a contacts the mark b on the backlash indicator.

Backlash indicator 4: 90890-06706 Magnet base plate 5: 90890-07003 Dial gauge set 6: 90890-01252 Magnet base B 7: 90890-06844 5. Slowly turn the drive shaft clockwise and counterclockwise and measure the backlash when the drive shaft stops in each direction.

NOTE: Tighten the propeller nut B while turning the drive shaft until the drive shaft can no longer be turned.

9. Slowly turn the drive shaft clockwise and counterclockwise and measure the backlash when the drive shaft stops in each direction.

Forward gear backlash: 0.30–0.72 mm (0.0118–0.0283 in) 6. Add or remove shim(s) if out of specification.

Forward gear backlash

Shim thickness

Less than 0.30 mm (0.0118 in)

To be decreased by (0.51 – M) × 0.49

More than 0.72 mm (0.0283 in)

To be increased by (M – 0.51) × 0.49

M: Measurement

Reverse gear backlash: 0.92–1.65 mm (0.0362–0.0650 in)

Available shim thicknesses: 1.0, 1.1, 1.2, 1.3, and 1.4 mm

6D55F11

6-28

1 2 3 4 5 6 7 8 9

LOWR

Lower unit

10. Add or remove shim(s) if out of specification.

Reverse gear backlash

Shim thickness

Less than 0.92 mm (0.0362 in)

To be decreased by (1.29 – M) × 0.49

More than 1.65 mm (0.0650 in)

To be increased by (M – 1.29) × 0.49

M: Measurement Available shim thicknesses: 1.0, 1.1, 1.2, and 1.3 mm 11. Remove the special service tools, and then install the water pump assembly.

6-29

6D55F11

BRKT

Bracket unit Tiller handle .................................................................................................... 7-1 Assembling the tiller handle....................................................................... 7-3 Bottom cowling .............................................................................................. 7-4 Upper case, steering arm ..............................................................................7-6 Draining the engine oil............................................................................. 7-10 Disassembling the oil pan........................................................................7-10 Checking the oil strainer ..........................................................................7-10 Checking the oil pan ................................................................................ 7-10 Assembling the oil pan ............................................................................7-10 Removing the steering arm ..................................................................... 7-11 Installing the steering arm ....................................................................... 7-12 Installing the upper case..........................................................................7-12 Clamp brackets, swivel bracket.................................................................. 7-13 Removing the clamp brackets .................................................................7-16 Disassembling the swivel bracket............................................................ 7-16 Assembling the swivel bracket ................................................................7-16 Installing the clamp brackets ................................................................... 7-17

6D55F11

1 2 3 4 5 6 7 8 9

BRKT

Bracket unit

Tiller handle

No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

7-1

Part name Throttle cable Engine stop lanyard switch Nut Grommet Shift link rod Shift lever Washer Wave washer Collar Nut Bolt Self-locking nut Nut Cable guide Bushing Steering bracket Plastic washer

7

Q’ty 2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1

Remarks

M6 × 30 mm

6D55F11

Tiller handle 7

No. 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33

Part name Metal washer Wave washer Bushing Tiller handle bracket Throttle friction adjuster Throttle grip Screw Washer Spring Bushing Throttle shaft Friction piece Bolt Plate Nut Engine stop lanyard

6D55F11

Q’ty 2 2 1 1 1 1 1 1 1 1 1 1 2 1 2 1

1 2 3 4 5 6 7 8 9

Remarks

ø5 × 25 mm

M6 × 20 mm

7-2

BRKT

Bracket unit

Assembling the tiller handle 1. Install the engine stop lanyard switch 1 to the tiller handle bracket 2. Tighten the nut to the specified torque.

2. Install the throttle cables 3 and 4 to the throttle shaft 5.

A

T.

3

NOTE: • Route the engine stop lanyard switch lead 9 and throttle cables 0 and A as shown.

• Install the corrugated tubes B so that they contact the tiller handle bracket C.

R.

4

Tiller handle bracket nut 7: 10 N·m (1.0 kgf·m, 7.4 ft·lb) Self-locking nut 8: 22 N·m (2.2 kgf·m, 16.2 ft·lb)

2

5

1

S6D57020

T. R.

Engine stop lanyard switch nut: 2 N·m (0.2 kgf·m, 1.5 ft·lb)

3. Install the shift lever to the steering bracket 6.

4. Install the washers and bushings into the steering bracket 6.

5. Install the tiller handle bracket to the steering bracket 6, tighten the tiller handle bracket nut 7 to the specified torque, and then tighten the self-locking nut 8 to the specified torque.

9 C

0

A

6 7B 8

7-3

S6D57030

6D55F11

Tiller handle / Bottom cowling

Bottom cowling

No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

Part name Shift rod lever joint Bolt Bracket Start-in-gear protection lever Shift rod lever Shift rod Bottom cowling Rubber seal Grommet Grommet Grommet Grommet Socket cord assembly Cable holder Bolt Spring Bolt

6D55F11

7

Q’ty 1 4 2 1 1 1 1 1 6 1 1 1 1 1 1 1 4

1 2 3 4 5 6 7 8 9

Remarks Remote control model M6 × 25 mm

Remote control model Remote control model Tiller handle model Remote control model M6 × 20 mm M6 × 30 mm

7-4

BRKT

Bracket unit 7

No. 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34

7-5

Part name Grommet Collar Water outlet Bolt Hook Bolt Lever Bushing Bushing Wave washer Washer Cowling lock lever Grommet Grommet Cable guide Bolt Retaining plate

Q’ty 4 4 1 1 1 1 1 1 1 1 1 1 1 1 1 2 1

Remarks

M6 × 20 mm

Tiller handle model Remote control model Remote control model M6 × 30 mm

6D55F11

Bottom cowling / Upper case, steering arm

Upper case, steering arm

No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

Part name Mount housing Rubber damper Rubber damper Bolt Bolt Nut Screw Ground lead Grease nipple Bolt Upper mount Plate Bolt Upper case assembly Nut Steering arm Washer

6D55F11

7

Q’ty 2 2 1 2 2 4 1 1 1 3 1 1 2 1 2 1 1

1 2 3 4 5 6 7 8 9

Remarks

M10 × 80 mm M10 × 120 mm ø6 × 8 mm

M8 × 30 mm

M8 × 185 mm

7-6

BRKT

Bracket unit 7

No. 18 19 20 21 22 23 24 25 26 27

7-7

Part name Bushing Straight key Bushing O-ring Bushing Nut Washer Steering hook Bolt Rubber seal

Q’ty 1 1 1 1 1 2 2 1 1 1

Remarks

Not reusable

Remote control model Remote control model Remote control model M8 × 20 mm

6D55F11

Upper case, steering arm 7

No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

Part name Upper case Screw Baffle plate Dowel Bolt Gasket Bolt Washer Bracket Exhaust manifold Gasket Oil pan Gasket Drain bolt Damper Dowel Bolt

6D55F11

Q’ty 1 2 1 2 4 1 3 3 1 1 1 1 1 1 1 2 10

1 2 3 4 5 6 7 8 9

Remarks ø5 × 15 mm

M8 × 30 mm M6 × 50 mm

Not reusable Not reusable

M14 × 12 mm

M6 × 25 mm

7-8

BRKT

Bracket unit 7

No. 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34

7-9

Part name Gasket Exhaust guide Oil seal Grommet Anode Cover Bolt Cover Bolt Cooling water pipe Rubber seal Bolt Oil strainer Bolt Gasket Relief valve housing Relief valve

Q’ty 1 1 1 1 1 1 1 1 1 1 1 2 1 3 1 1 1

Remarks Not reusable Not reusable

M5 × 12 mm M6 × 20 mm

M6 × 16 mm M6 × 25 mm Not reusable

6D55F11

Upper case, steering arm

Draining the engine oil 1. Place a drain pan under the drain hole, and then remove the drain bolt and let the oil drain completely.

2. Remove the upper and lower mounting nuts, and then remove the upper case.

2. Check the cooling water pipe for deformation or corrosion. Replace if necessary.

3. Check the relief valve for clogs or damage. Replace if necessary.

Assembling the oil pan 3. Remove the muffler assembly from the upper case.

1. Install new gaskets onto the exhaust guide 1.

Disassembling the oil pan

2. Install the relief valve assembly 2 and bolts.

1. Remove the exhaust manifold and seal from the oil pan.

2. Remove the oil pan 1 from the exhaust guide 2.

3. Remove the oil strainer 3 and relief valve assembly 4 from the exhaust guide 2.

3. Install the oil strainer 3 and bolts.

Checking the oil strainer 1. Check the oil strainer for dirt and residue.

Clean if necessary.

Checking the oil pan 1. Check the exhaust guide and exhaust manifold for damage or corrosion.

Replace if necessary.

6D55F11

7-10

1 2 3 4 5 6 7 8 9

BRKT

Bracket unit

4. Install the cooling water pipe 4.

5. Install the oil pan 5 and bolts, and then tighten the bolts finger tight.

6. Install the exhaust manifold 6, seal, and bolts, and then tighten the bolts finger tight.

7. Tighten the oil pan bolts 7, and tighten the exhaust manifold bolts 8 to the specified torque.

T. R.

Engine oil drain bolt: 27 N·m (2.7 kgf·m, 20.0 ft·lb) Upper case bolt 0: 21 N·m (2.1 kgf·m, 15.5 ft·lb)

11. Install the upper mount A and bolts B into the upper case, and then tighten the bolts to the specified torque.

T. R.

Exhaust manifold bolt 8: 10 N·m (1.0 kgf·m, 7.4 ft·lb)

8. Install the muffler assembly 9 into the upper case.

7-11

R.

10. Install the upper case bolts 0, and then tighten them to the specified torque.

T.

9. Install a new gasket and the engine oil drain bolt, and then tighten the bolt to the specified torque.

Upper mount bolt: 27 N·m (2.7 kgf·m, 20.0 ft·lb)

Removing the steering arm 1. Remove the steering arm from the swivel bracket by pulling the arm off the bracket.

6D55F11

Upper case, steering arm

Installing the steering arm 1. Install the washer 1, bushing 2, and straight key 3 onto the steering arm 4.

4. Tighten the lower mounting nuts 5 to the specified torque, then tighten the lower mounting nuts 7 to the specified torque.

1 2 3 4 5 6 7 8 9

2. Place the swivel bracket 5 in an upright position, and then install the steering arm onto the bracket.

T. R.

3. Install the bushing 6, new O-ring 7, and bushing 8 onto the swivel bracket.

Upper mounting nut 2: 24 N·m (2.4 kgf·m, 17.7 ft·lb) Lower mounting nut 5 and 7: 54 N·m (5.4 kgf·m, 39.8 ft·lb)

Installing the upper case 1. Install the upper mounting bolts into the swivel bracket 1.

2. Install the upper mounting nuts 2 and then tighten them to the specified torque.

3. Install the lower mount housing 3, lower mounting bolts 4, lower mounting nuts 5, lower mounting bolts 6, and lower mounting nuts 7, and then tighten the nuts finger tight.

6D55F11

7-12

BRKT

Bracket unit

Clamp brackets, swivel bracket

No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

7-13

Part name Tilt pin Spring Bolt Collar Washer Nut Cap nut Self-locking nut Plate Through tube Clamp bracket Washer Bushing Swivel bracket Clamp bracket Nut Washer

7

Q’ty 1 1 1 1 1 1 2 2 1 1 1 2 2 1 1 2 2

Remarks

M8 × 255 mm

6D55F11

Clamp brackets, swivel bracket 7

No. 18 19 20 21 22 23 24 25 26 27 28

Part name Plastic washer Tilt stopper plate Wave washer Bolt Pin Bushing Pin Circlip Collar Bushing Grease nipple

6D55F11

Q’ty 2 2 2 2 1 2 1 2 1 1 3

1 2 3 4 5 6 7 8 9

Remarks

7-14

BRKT

Bracket unit 7

No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

7-15

Part name Spring Tilt lock rod Tilt lever Screw Collar Circlip Tilt lock lever Bushing Pin Bushing Tilt support bar Spring Pin 1 Pin 2 Tilt lock plate Tilt lock arm Collar

Q’ty 1 1 1 1 1 1 1 1 1 1 1 2 1 1 2 1 1

Remarks

ø5 × 5 mm

6D55F11

Clamp brackets, swivel bracket

Removing the clamp brackets 1. Remove the tilt pin, and then remove the clamp bracket bolt, clamp bracket nut, and collar.

3. Install the tilt support bar A and pin B, and then insert the tilt lock lever C partially into the swivel bracket.

2. Remove the tilt stopper plate nuts and tilt stopper plate bolts.

3. Remove the cap nuts, then the self-locking nuts and plate.

4. Remove the through tube, then disassemble the clamp brackets.

5. Remove the pins, tilt stopper plates, and bushings.

Disassembling the swivel bracket 1. Remove the tilt lock lever, tilt lever spring, tilt lock rod, pin, and tilt support bar.

2. Remove the bushings and collar.

4. Hook the tilt lock rod D onto the tilt lever E and the pin 2 3, hook the spring F onto the tilt lever E and the tilt support bar A, and then insert the tilt lock lever C into the tilt lever E completely.

3. Remove the pin 1, pin 2, collar, tilt lock plates, tilt lock arm, and springs.

Assembling the swivel bracket 1. Install the tilt lock arm 1, tilt lock plates 2, pin 2 3, pin 1 4, collar 5, springs 6 to the swivel bracket 7.

2. Install the bushings 8 and 9 and collar 0 to the swivel bracket.

6D55F11

7-16

1 2 3 4 5 6 7 8 9

BRKT

Bracket unit

H E

R.

G

T.

5. Install the screw G to the tilt lever E, and then install the circlip H to the pin B.

Tilt stopper plate nut: 24 N·m (2.4 kgf·m, 17.7 ft·lb) Self-locking nut 1: 45 N·m (4.5 kgf·m, 33.2 ft·lb) Clamp bracket nut 4: 8 N·m (0.8 kgf·m, 5.9 ft·lb)

B 6. Apply water resistant grease to the grease nipples.

S6D57220

NOTE: After installation, check the tilt lock lever for proper operation.

T. R.

Tilt lever screw: 4 N·m (0.4 kgf·m, 3.0 ft·lb)

Installing the clamp brackets 1. Install the bushings, tilt stopper plates, and pins to the swivel bracket assembly.

NOTE: Apply the grease until it comes out of the bushings a.

2. Assemble the clamp brackets, washers, and swivel bracket, and then install the through tube.

3. Install the plate, tighten the self-locking nuts 1 to the specified torque, and then tighten the cap nuts.

4. Install the tilt stopper plate bolts and tilt stopper plate nuts, and then tighten the nuts to the specified torque.

5. Install the collar 2 and clamp bracket bolt 3, and then tighten the clamp bracket nut 4 to the specified torque.

7-17

6D55F11

ELEC

–

+

Electrical systems Special service tools .....................................................................................8-1 Checking the electrical components............................................................ 8-2 Measuring the peak voltage ...................................................................... 8-2 Measuring the lower resistance.................................................................8-2 Electrical components................................................................................... 8-3 Front and aft views .................................................................................... 8-3 Port and starboard views...........................................................................8-4 Wiring diagram .......................................................................................... 8-5 Checking the ignition spark gap ................................................................8-7 Checking the spark plug caps ...................................................................8-7 Checking the ignition coil...........................................................................8-7 Checking the CDI unit................................................................................ 8-8 Checking the pulser coil ............................................................................8-8 Checking the charge coil ...........................................................................8-9 Checking the power bobbin ....................................................................... 8-9 Checking the lighting coil...........................................................................8-9 Checking the engine stop lanyard switch ................................................ 8-10 Checking the thermo sensor.................................................................... 8-10 Checking the oil pressure switch ............................................................. 8-10 Checking the oil pressure warning indicator............................................8-11

6D55F11

1 2 3 4 5 6 7 8 9

ELEC

–

+

Electrical systems

Special service tools

8

Ignition tester 90890-06754

Digital circuit tester 90890-03174

Peak voltage adapter B 90890-03172

Test harness (2 pins) New: 90890-06868 Current: 90890-06768

Vacuum/pressure pump gauge set 90890-06756

8-1

6D55F11

Special service tools / Checking the electrical components

Checking the electrical components

Measuring the lower resistance 8

Measuring the peak voltage NOTE: Before troubleshooting the peak voltage, check that all electrical connections are tight and free from corrosion, and that the battery is fully charged to 12 V. The condition of the ignition system can be determined by measuring the peak voltage.

Cranking speed is effected by many factors, such as fouled or weak spark plugs, or a weak battery. If one of these factors is present, the peak voltage will be lower than specification. In addition, if the peak voltage is lower than specification the engine will not operate properly.

When measuring a resistance of 10 Ω or less with the digital circuit tester, the correct measurement cannot be obtained due to the internal resistance of the tester. To obtain the correct value, subtract the internal resistance from the displayed measurement.

NOTE: To obtain the internal resistance of the digital circuit tester, connect both of its probes and check the display.

Correct value = displayed measurement – internal resistance

DC V

S69J8020

WARNING When checking the peak voltage, do not touch any of the connections of the digital tester leads.

NOTE: • Use the peak voltage adapter with the digital circuit tester.

• When measuring the peak voltage, set the selector on the digital circuit tester to the DC voltage mode.

• Connect the positive pin on the peak voltage adapter to the positive terminal of the digital circuit tester.

6D55F11

8-2

1 2 3 4 5 6 7 8 9

ELEC

–

+

Electrical systems

Electrical components

8

Front and aft views

1 CDI unit 2 Ignition coil 3 Engine stop lanyard switch coupler (remote control model)

8-3

6D55F11

Electrical components

Port and starboard views

1 2 3 4 5

1 2 3 4 5 6 7 8 9

Oil pressure switch Thermo sensor Pulser coil Spark plugs Prime Start

6D55F11

8-4

ELEC

–

+

Electrical systems

Wiring diagram 1 2 3 4 5 6 7 8 9 0

CDI unit Oil pressure switch Stator coil Pulser coil Thermo sensor Ignition coil Wiring harness Prime Start Engine stop lanyard switch Oil pressure warning indicator

8-5

Color code B O P R W Y B/W Br/B G/W P/W R/W W/G Y/B Y/R

: Black : Orange : Pink : Red : White : Yellow : Black/white : Brown/black : Green/white : Pink/white : Red/white : White/green : Yellow/black : Yellow/red

6D55F11

6D55F11

0

9

W

P

Y/R

W

P/W

Br/B

R/W

A

Y/R

F25CMH, F25CM

P

Y/R

Y Y

G/W

W/G

B

1

8

Y

Y

Y/B Y

Y

Y/B

P/W

O B/W

2

P

P

7

Y/B

G/W

Y/B

Y/B

Y/B

W/G

G/W

W/G

3

R/W

C B

R

B

W

4

A

B B

B

Br/B R/W

P

P/W

Y/R

Y

O

Br/B

Br/B

Y

B

B/W

B

O

O

G/W

B

B/W

5

W/G

Br/B

Br/B

Y

Y

R/W

R

C

6

W

Electrical components

1 2 3 4 5 6 7 8 9

S6D5WD01

8-6

ELEC

–

+

Electrical systems

Checking the ignition spark gap 1. Disconnect the spark plug caps from the spark plugs.

2. Connect a spark plug cap to the special service tool.

2. Measure the spark plug cap resistance.

Replace if out of specification.

S6D58040

Ignition tester: 90890-06754 3. Crank the engine and observe the spark through the discharge window of the spark gap tester. Check the ignition system if the spark is weak.

Spark plug cap resistance: 4–6 kΩ

Checking the ignition coil 1. Remove the spark plug caps from the spark plug wires by turning the caps counterclockwise.

2. Disconnect the ignition coil connectors.

S6D58050

WARNING

3. Measure the ignition coil resistance.

Replace if out of specification.

• Do not touch any of the connections of the spark gap tester leads.

• Do not let sparks leak out of the removed spark plug caps.

• Keep flammable gas or liquids away, since this test can produce sparks.

Checking the spark plug caps 1. Remove the spark plug caps from the spark plug wires by turning the caps counterclockwise.

8-7

S6D58070

6D55F11

Electrical components Ignition coil resistance: Primary coil: Orange (O) – Black (B) 0.08–0.11 Ω at 20 °C (68 °F) Secondary coil: Spark plug wire – spark plug wire 3.4–4.7 kΩ at 20 °C (68 °F)

R W

R/W B

S6D58090

Checking the CDI unit 1. Measure the CDI unit output peak voltage. If below specification, measure the pulser coil output peak voltage. Replace the CDI unit if the output peak voltage of the pulser coil is above specification.

Digital circuit tester: 90890-03174 Peak voltage adapter B: 90890-03172 Test harness (2 pins): New: 90890-06868 Current: 90890-06768 Pulser coil output peak voltage: Red (R) – White (W) r/min DC V

Digital circuit tester: 90890-03174 Peak voltage adapter B: 90890-03172

Unloaded

Loaded

Cranking 6.0

5.7

1,500

3,500

14.0

20.4

Pulser coil resistance (reference data): Red (R) – White (W) 300–350 Ω at 20 °C (68 °F)

CDI unit output peak voltage: Black/white (B/W) – Orange (O) r/min DC V

Loaded Cranking

1,500

3,500

120

120

130

Checking the pulser coil 1. Disconnect the pulser coil coupler.

2. Connect the test harness (2 pins) to the pulser coil.

3. Measure the pulser coil output peak voltage. Replace the pulser coil if below specification.

6D55F11

8-8

1 2 3 4 5 6 7 8 9

ELEC

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Electrical systems

Checking the charge coil Digital circuit tester: 90890-03174 Peak voltage adapter B: 90890-03172

1. Measure the charge coil output peak voltage. Replace the stator coil if below specification.

Power bobbin output peak voltage: Yellow/black (Y/B) – Yellow/black (Y/B) r/min DC V r/min Digital circuit tester: 90890-03174 Peak voltage adapter B: 90890-03172

DC V

DC V

Unloaded

1,500

3,500

10.0

38.9

80.0

Loaded Cranking

1,500

3,500

5.5

30.0

80.0

Loaded

Cranking 170

Cranking

Power bobbin resistance (reference data): Yellow/black (Y/B) – Yellow/black (Y/B) 6.50–7.20 Ω at 20 °C (68 °F)

Charge coil output peak voltage: Green/white (G/W) – White/green (W/G) r/min

Unloaded

130

1,500

3,500

140

140

Checking the lighting coil 1. Measure the lighting coil output peak voltage. Replace the stator coil if below specification.

Charge coil resistance (reference data): Green/white (G/W) – White/green (W/G) 660–710 Ω at 20 °C (68 °F)

Checking the power bobbin 1. Measure the power bobbin output peak voltage. Replace the stator coil if below specification.

Digital circuit tester: 90890-03174 Peak voltage adapter B: 90890-03172 Lighting coil output peak voltage: Yellow (Y) – Yellow (Y) r/min DC V

8-9

Unloaded Cranking

1,500

3,500

9.4

46.0

95.0

6D55F11

Electrical components Lighting coil resistance (reference data): Yellow (Y) – Yellow (Y) 0.90–1.10 Ω at 20 °C (68 °F)

Checking the engine stop lanyard switch 1. Check the engine stop lanyard switch for continuity. Replace if out of specification.

2. Measure the thermo sensor resistance.

Replace if out of specification.

Thermo sensor resistance: Brown/black (Br/B) – Brown/black (Br/B) at 20 °C (68 °F): 1.13–1.38 kΩ at 50 °C (122 °F): 324–396 Ω at 80 °C (176 °F): 113–139 Ω

Checking the oil pressure switch 1. Connect the special service tool to the oil pressure switch.

2. Slowly operate the special service tool.

Switch position

Lead color White (W) Black (B)

Clip removed a

3. Check the switch for continuity at the specified pressure. Replace if there is no continuity.

Clip installed b Vacuum/pressure pump gauge set: 90890-06756

Engine stop button pushed c

Checking the thermo sensor 1. Place the thermo sensor in a container of water and slowly heat the water.

Specified oil pressure: 15.5 kPa (0.16 kgf/cm2, 2.25 psi)

S69J8250

6D55F11

8-10

1 2 3 4 5 6 7 8 9

ELEC

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Electrical systems

Checking the oil pressure warning indicator 1. Connect a penlight battery (1.5 V) to the oil pressure warning indicator (LED).

Replace if it does not light.

CAUTION: Only use a penlight battery (1.5 V) when checking the LED. Other batteries (e.g., alkaline batteries or high-voltage batteries) will damage the diode.

NOTE: • The LED will not light if the penlight battery voltage is less than 1.5 V. • The LED only allows current to flow in one direction. Therefore, if the LED does not light, reverse the connection.

• If the oil pressure warning indicator is installed to the outboard motor, start the engine and ground the pink (P) lead to check if the LED lights.

8-11

6D55F11

TRBL SHTG

Troubleshooting Power unit....................................................................................................... 9-1

6D55F11

1 2 3 4 5 6 7 8 9

TRBL SHTG

Troubleshooting

NOTE: • Before troubleshooting the outboard motor, check the compression pressure, valve clearance, the mounting and rigging of the outboard motor, and the operation of the manual starter. Also, make sure that specified fuel has been used.

• Check that all electrical connections are tight and free from corrosion.

• To diagnose a mechanical malfunction, use the troubleshooting charts for each trouble located in this chapter. Also, when checking and maintaining the outboard motor, see Chapters 3–8 for safe maintenance procedures.

Power unit

9

Symptom 1: Engine does not start, or starting the engine is difficult.

• Manual starter is operating normally.

• Air vent screw on the fuel tank is open.

Ignition system Check the engine stop lanyard switch for continuity (with clip installed).

Is there continuity?

Yes

Replace the engine stop lanyard switch.

No Check the condition of the spark plugs.

No

Good condition?

Clean, adjust, or replace the spark plugs.

Yes Check the ignition spark using the spark gap tester.

WARNING • Do not touch any of the connections of the spark gap tester leads.

• Do not let sparks leak out of the removed spark plug caps.

• Keep flammable gas and liquids away, since this test can produce sparks.

Continued on next page.

9-1

6D55F11

Power unit

Good spark?

Yes

1 2 3 4 5 6 7 8 9

Check the fuel system.

No Check the ignition coil resistance.

Good condition?

No

Replace the ignition coil.

Yes Check the spark plug cap resistance and the spark plug caps for salt buildup.

Good condition?

No

Repair or replace the spark plug caps.

Yes Check the charge coil output peak voltage.

Good condition?

No

Replace the stator coil.

Yes Check the pulser coil output peak voltage or resistance.

Good condition?

No

Replace the pulser coil.

Yes Check the CDI unit output peak voltage.

Continued on next page.

6D55F11

9-2

TRBL SHTG

Troubleshooting

Good condition?

Yes

Check the fuel system.

No Replace the CDI unit.

Fuel system Check the fuel filter for clogs and the hoses for leaks.

Clogs or leaks?

Yes

Repair or replace the defective parts.

No Check the fuel pump diaphragms.

Cracks or damage?

Yes

Replace the diaphragms.

No Disassemble the carburetor and check the internal parts for clogs, debris, or wear.

Clogs, debris, or wear?

Yes

Clean or replace the defective parts.

No Check the ignition system.

9-3

6D55F11

Power unit Symptom 2: Engine speed at wide open throttle is low, engine speed decreases, or engine stalls (poor acceleration or poor deceleration).

Symptom 3: Engine speed not stable at low speeds.

• Air vent screw on the fuel tank is open.

• Check the throttle cable and link operation.

• Check the ignition system.

Fuel system Check the fuel filter for clogs and the hoses for leaks.

Clogs or leaks?

Yes

Repair or replace the defective parts.

No Check the fuel pump diaphragms.

Cracks or damage?

Yes

Replace the diaphragms.

No Check the throttle valve operation.

Good condition?

No

Repair or replace the defective parts.

Yes Check the pilot screw setting.

Continued on next page.

6D55F11

9-4

1 2 3 4 5 6 7 8 9

TRBL SHTG

Troubleshooting

Within specification?

No

Adjust the pilot screw.

Yes Disassemble the carburetor and check the internal parts for clogs, debris, or wear.

Clogs, debris, or wear?

Yes

Clean or replace the defective parts.

No Check the ignition system or lubrication system.

9-5

6D55F11

Power unit Lubrication system

1 2 3 4 5 6 7 8 9

Check the engine oil level.

At specified level?

No

Add engine oil to the correct level.

No

Check the oil pump for debris or oil leaks.

Yes Check the oil pressure.

Within specification?

Yes

Debris or leaks?

No

Check the oil passage.

Yes Clean or replace the defective parts.

Check the oil pressure switch.

Good condition?

No

Replace the oil pressure switch.

Yes Check the thermo sensor.

Good condition?

No

Replace the thermo sensor.

Yes Check the ignition system or the fuel system.

6D55F11

9-6

Index

A. Adjusting the throttle cable (remote control model)..............................3-8 Adjusting the throttle cables (tiller handle model) ..................................3-8 Adjusting the throttle link.............................3-7 Adjusting the throttle stop screw ...............4-13 After test run .............................................1-10 Applicable models.......................................1-5 Assembling the carburetor ........................4-12 Assembling the drive shaft........................6-18 Assembling the forward gear ....................6-18 Assembling the fuel pump...........................4-6 Assembling the lower case .......................6-17 Assembling the manual starter .................5-13 Assembling the oil pan..............................7-10 Assembling the oil seal housing................6-14 Assembling the pistons and cylinder block ..........................................5-44 Assembling the propeller shaft assembly.................................................6-12 Assembling the propeller shaft housing ....6-13 Assembling the swivel bracket..................7-16 Assembling the tiller handle ........................7-3

B. Backlash ...................................................6-27 Bottom cowling............................................7-4 Bracket......................................................3-11 Break-in.....................................................1-10

C. Carburetor...................................................4-9 Carburetor unit ............................................4-8 Changing the engine oil ..............................3-4 Changing the gear oil................................3-12 Checking the anodes ................................3-13 Checking the balancer ..............................5-37 Checking the bearings ..............................6-17 Checking the camshaft .............................5-29 Checking the carburetor............................4-11 Checking the CDI unit .................................8-8 Checking the charge coil.............................8-9 Checking the compression pressure...........5-3 Checking the connecting rod big end side clearance.........................................5-40 Checking the connecting rod small end inside diameter........................................5-40 Checking the cooling water passage ..........3-7 Checking the cooling water pilot holes........1-9 Checking the crankpin oil clearance .........5-41 Checking the crankshaft ...........................5-40

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Checking the crankshaft main journal oil clearance ................................................ 5-42 Checking the cylinder bore ....................... 5-37 Checking the cylinder head ...................... 5-29 Checking the diaphragms and valves......... 4-6 Checking the drive shaft ........................... 6-17 Checking the electrical components........... 8-2 Checking the engine idle speed ............... 3-10 Checking the engine oil .............................. 3-4 Checking the engine oil level...................... 1-6 Checking the engine stop lanyard switch...............................................1-9, 8-10 Checking the fuel filter ................................ 3-3 Checking the fuel joint ................................ 4-7 Checking the fuel joint and fuel hoses (fuel joint-to-carburetor) ............................ 3-3 Checking the fuel pump.............................. 4-5 Checking the fuel system ........................... 1-6 Checking the gear oil level ................1-6, 3-11 Checking the gear shift and throttle operation....................................... 1-8 Checking the gear shift operation (remote control model) ............................. 3-9 Checking the gear shift operation (tiller handle model) .................................. 3-9 Checking the ignition coil............................ 8-7 Checking the ignition spark gap ................. 8-7 Checking the ignition timing...................... 3-10 Checking the lighting coil............................ 8-9 Checking the lower case .......................... 6-17 Checking the lower unit for air leakage .... 3-12 Checking the oil pan ................................. 7-10 Checking the oil pressure ........................... 5-3 Checking the oil pressure switch .............. 8-10 Checking the oil pressure warning indicator .................................................. 8-11 Checking the oil pump .............................. 5-30 Checking the oil strainer ........................... 7-10 Checking the outboard motor mounting height........................................................ 1-7 Checking the pinion and forward gear...... 6-17 Checking the piston clearance ................. 5-38 Checking the piston diameter ................... 5-37 Checking the piston pin ............................ 5-39 Checking the piston pin boss bore ........... 5-39 Checking the piston ring grooves ............. 5-39 Checking the piston ring side clearance... 5-39 Checking the piston rings ......................... 5-38 Checking the power bobbin ........................ 8-9 Checking the Prime Start.......................... 4-12 Checking the propeller.............................. 3-12 Checking the propeller shaft and shift rod................................................... 6-12

6D55F11

Index Checking the propeller shaft housing........6-12 Checking the pulser coil..............................8-8 Checking the remote control cables (remote control model)..............................1-7 Checking the rocker arms and rocker arm shaft ......................................5-28 Checking the spark plug caps.....................8-7 Checking the spark plugs............................3-6 Checking the spiral spring.........................5-13 Checking the start-in-gear protection..........3-9 Checking the steering system.....................1-8 Checking the thermo sensor .....................8-10 Checking the thermostat .............................3-6 Checking the tilt operation ........................3-11 Checking the timing belt..............................3-5 Checking the timing belt and sprockets ....5-17 Checking the top cowling ............................3-3 Checking the valve clearance .....................5-4 Checking the valve guides ........................5-25 Checking the valve seat............................5-26 Checking the valve springs .......................5-24 Checking the valves..................................5-24 Checking the water pump ...........................6-8 Clamp brackets, swivel bracket ................7-13 Control system ............................................3-7 Cylinder block ...........................................5-33 Cylinder head............................................5-20

F. Fire prevention............................................ 1-3 Front and aft views ..................................... 8-3 Fuel hoses and fuel filter ............................ 4-3 Fuel pump................................................... 4-4 Fuel system ................................................ 3-3

G. General..................................................... 3-13 General specifications ................................ 2-1 General torques........................................ 2-13 Good working practices .............................. 1-4

H. Hose routing ............................................... 4-2 How to use this manual .............................. 1-1

I. Identification ............................................... 1-5 Installing the camshaft.............................. 5-31 Installing the clamp brackets .................... 7-17 Installing the cylinder head ....................... 5-47 Installing the lower unit ............................. 6-21 Installing the oil pump............................... 5-32 Installing the pinion................................... 6-19 Installing the power unit............................ 5-49 Installing the propeller shaft housing ........ 6-19 Installing the rocker arm shaft assembly .. 5-32 Installing the sprockets and timing belt..... 5-17 Installing the starter rope .......................... 5-14 Installing the steering arm ........................ 7-12 Installing the upper case........................... 7-12 Installing the valves .................................. 5-30 Installing the water pump and shift rod..... 6-19

D. Dimensions .................................................2-9 Disassembling the cylinder block..............5-36 Disassembling the drive shaft ...................6-16 Disassembling the forward gear ...............6-16 Disassembling the fuel pump......................4-5 Disassembling the lower case ..................6-16 Disassembling the manual starter.............5-13 Disassembling the oil pan .........................7-10 Disassembling the oil seal housing...........6-12 Disassembling the propeller shaft assembly.................................................6-11 Disassembling the propeller shaft housing ...................................................6-11 Disassembling the swivel bracket .............7-16 Disassembly and assembly ........................1-4 Draining the engine oil ..............................7-10 Drive shaft and lower case........................6-15

E. Electrical .....................................................2-7 Electrical components.................................8-3

6D55F11

L. Lower unit .................................. 2-7, 3-11, 6-4 Lubricating the outboard motor................. 3-13

M. Maintenance interval chart ......................... 3-2 Maintenance specification .......................... 2-3 Manual format............................................. 1-1 Measuring the forward and reverse gear backlash ................................................. 6-27 Measuring the lower resistance.................. 8-2 Measuring the peak voltage ....................... 8-2 Measuring the starter rope ....................... 5-13

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1 2 3 4 5 6 7 8 9

Index

P. Parts, lubricants, and sealants....................1-3 Port and starboard views ............................8-4 Power unit ............................ 2-3, 3-4, 5-3, 9-1 Predelivery checks......................................1-6 Propeller selection ......................................1-5 Propeller shaft housing ...............................6-9 Propeller size ..............................................1-5

W. Wiring diagram ........................................... 8-5

R. Refacing the valve seat.............................5-26 Removing the carburetor ..........................4-11 Removing the clamp brackets...................7-16 Removing the cylinder head .....................5-23 Removing the drive shaft ..........................6-16 Removing the lower unit .............................6-7 Removing the power unit ..........................5-18 Removing the propeller shaft housing assembly.................................................6-11 Removing the steering arm.......................7-11 Removing the timing belt and sprockets ...5-15 Removing the water pump ..........................6-7 Replacing the oil filter..................................3-5 Replacing the valve guides .......................5-25

S. Safety while working ...................................1-3 Selecting the connecting rod bearing........5-42 Selecting the crankshaft main bearing......5-43 Selecting the forward gear shims..............6-25 Selecting the pinion shims ........................6-24 Selecting the reverse gear shims..............6-26 Selection .....................................................1-6 Self-protection.............................................1-3 Serial number..............................................1-5 Shimming ........................................ 6-23, 6-24 Special service tools .... 3-1, 4-1, 5-1, 6-1, 8-1 Specified torques ......................................2-11 Symbols ......................................................1-2

T. Test run.......................................................1-9 Tightening torques ....................................2-11 Tiller handle ................................................7-1 Top cowling.................................................3-3

U. Upper case, steering arm............................7-6

V. Ventilation ...................................................1-3

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6D55F11

YAMAHA MOTOR CO., LTD.

Printed in Japan Nov. 2003 – 0.4 × 1 CR (E)

Printed on recycled paper