Parsun F4/F5 Outboard Engine Service Manual

Table of Contents

General Information

Identification

The outboard motor serial number is marked on the label.The label can be found on the bracket left assembly or on the upper part ofthe bracket swivel.Record your outboard motor serial number in the spaces provided to assist you in ordering spare parts from yourParsun dealer or for reference in case your outb oard motoris stolen.

Outboard motor serial number label location

  • 1.Outboardmotorserialnumberlocation Serial number as follows:

PRODUCTION CODE

Production code format on serial number label

Serial number label decoding diagram

Propeller Selection

The performance of your outboard motor will be critically affected by your choice of propeller, as an incorrect choice could adversely affect performance.

For a greater boat load and a low engine speed, a smaller-pitch propeller is more suitable. correct engine speed to be maintained.

When the engine is running at full throttle position, the suitable propeller should be used according performance.

Propeller sizesMaterial
71/4x8Aluminum alloy
71/2x7Aluminum alloy
71/4×61/2Aluminum alloy

Emergency Start

Ifthe starting device isnot working,the engine can be started by emergency start cable. /WARNING:

  • The start program can only be used in emergency and to return to harbor for repairing.
  • not working. So please ensure the shift rod is in NEUTRAL position.
  • Please ensure nobody standing behind you in case the cable is pulled out to hurt people.
  • After the engine starts up,don't fit the start device or top cowling.Put clothing or other
  • When starting and operating, don't touch ignition coil, spark plug cap or other electric

The procedure is as follows:

  • 1.Remove the top cowling.
  • 2.Remove the start-in-gear protection device cable,and remove the chock lever cable.
  • 1.Start-in-gear protection device cable
  • 3.Demount threebolts and remove starter.
  • 4.Assembletwobolts to fixthefuel tank.
  • 5.Insert the knot of the cable in the notch of flywheel rotor, and wind the cable around flywheel severalroundsin clockwisedirection.
  1. Pullthemanual starter.
  • 2.Chock lever cable

Start-in-gear protection device cable location

Choke lever cable location

Emergency start cable insertion into flywheel notch

Winding emergency start cable around flywheel

  1. Give a strong pull to start the engine. Repeat if necessary.

Safety While Working

To prevent the danger or accidents when performing maintenance and repair, and improve the work efficiency, please obey the following safety procedures.

1. Fire Prevention

Gasoline (petrol), lubricant and grease are highly flammable.While working,keep away from heat, sparks and open flames.

2. Ventilation

Petroleum vapor and engine exhaust gases are violent in toxicity.They are harmful to breathe and deadly if inhaled in large quantities. When test-running an engine indoors, maintain good ventilation.

3. Self-Protection

Protect your eyes with suitable safety glasses or safety goggles, when drilling, grinding or operating air compressor. Protect hands and feet by wearing protective work clothes, safety gloves and shoes if necessary.

4. Lubricants and Sealing Fluids

When performing maintenance procedures and repair to Parsun outboards, use only products provided or recommended by our Company.

Undernormalconditionsofuse,thereshouldbenohazardsfromtheuseofthelubricants mentioned in this manual, but safety is all-important, and by adopting good safety practices, any risk is minimized.

A summary of the most important precautions is as follows:

  • ① To protect the skin, the application of a suitable barrier cream to the hands before working is recommended.
  • Clothingwhich hasbecome contaminatedwith lubricants should be changed as soon as practicable, and washed before further use.
  • ③ Avoidskincontactwithlubricants.
  • ① Hands and any other part of the body which have been in contact with lubricants or lubricant-contaminatedclothing,should bethoroughlywashedwithhotwater andsoap as soon as practicable.
  • A supply of clean lint-free cloths should be available for wiping run-off lubricants or grease.

5. Good Working Practices

  • ① Follow the tightening torque instruction. When tightening bolts, nuts and screws, tighten the large sizes first, and tighten inner-positioned fixings before outer-positioned ones.
  • O Use the recommended special tools to protect parts from damage.Use the right tool in the right manner.

Disassembly and Assembly

When disassembly and assembly, please follow the following principles:

  • 1.Use specialtools when disassermbling and assembling.
  1. Clean dirt before disassemb ling the parts.
  • 3.Oil the contact surfaces of mov ing parts before assermbly.
  1. Install bearing with the manufacburer's markings on the side exposed to view and liberally oil the bearing.
  • 5.When installing oil seals, apply a light coating of water-resistant grease to the ledge and outside diarmeter.

One-Time Use Parts

One-time use parts are gasket, oil seal, O-ring, cotter pin and spring, ring, and etc. When re-assemb ling outb oard engine, you must change the one-time use parts.

Pre-Delivery Check

To ensure the using, please inspect the following before delivery.

1. Checking Fuel System

Check ifthe fuel pipe is connected firmly, and if the fuel is filled with fuel.

CAUTION: Do not use pre-mixed fuel for this 4 stoke outb oard engine.

2. Checking Oil Level

  • Check the engine oil level

Remove oil cap, check engine oil level.

Engine oil cap and dipstick location

  1. Oil cap 2. Oil rule 3. High position mark 4. Low position mark

Oil dipstick with high and low position marks

oil; if below lower mark, add engine oil up to upper level.

Check the gear oil level:

Remove the oil level plug.Check if the gear oil overflows at the oil level checking hole. If so, install the oil level plug and tighten it according to specified torque. Otherwise please add gear oil.

1.Oil level plug

Gear oil level plug location on lower unit

  • 3. Check Steering System: Check if steering is stable. Check if steering friction is adjusted correctly. Turn clamp handle screw clockwise to increase resistance. Turn clamp handle screw counter clockwise to lower resistance. 4. Check Shift Lever and Throttle: Check if the shift lever is operated smoothly.

Checkif the throttle grip is turned smoothly from full closed position to full open position.

5. Check Engine Stop Switch Assembly: Check stopper hang rope.

6. Check Cooling Water Checking Hole

When the engine is running, check if cooling water overflows at the cooling water checking hole.

1.Cooling water checking hole

Cooling water checking hole location

7. Breaking-In Running

  • ① Initial 1 hour: operate the engine at 2000 r/min or about a half throttle.
  • ② The second hour: operate the engine at 3000 r/min or about 3/4 throttle.
  • ? The following 8hours: operate the engine at fullthrottle continuously.Each operation time doesn't exceed 5 minutes.

8. Inspection After Breaking-In Running

  • Check if gear oil contains water.
  • ② Check if the fuel line leaks.
  • After breaking-in running, operate the engine at idling speed.Use cleaning tool to wash
  1. Clamp handle screw

Clamp handle screw for steering friction adjustment

over the coolingwater passage by fresh water.

  1. After breaking-in running, inspect idling speed.
    1. Preheating engine for 5 minutes.
  2. 2 Using the tachometer to measure idling speed RPM. If out of specification, adjust it. Idling speed: 1450~1550 r/min
  3. Turm the throttle stop screw clockwise or counter clockwise until the specified idling speed is attained.
  4. After adjusting idling speed, picking up RPM several times to check the engine's stability.

Throttle stop screw for idling speed adjustment

Special Tools and Detection Device

When performing maintenance and repair, you need to use all kinds of special tools and detection device.The use of correct tools will improve the work efficiency and avoid of the damage to the people and outboard engines.

Special Tools

Piston slider special tool

Piston slider

Valve spring compressor special tool

Valve spring compressor

Oil seal installer special tool

Oil seal installer tool

Flywheel holder and puller special tools

Flywheel holder and puller

Housing bearing installer special tool

Housingbearing installer

Housing oil seal installer special tool

Housing oil seal installer

Bearing puller special tool

Bearing puller

Lower casing cover bearing installer

Lower casing cover bearing installer special tool

Space gage

Space gauge detection device

Barrel bearing with guard board installer tool

Barrel bearing with guard boardinstaller tool

Lower casing bracket and barrel bearing without guard boardinstaller tool

Lower casing bracket and barrel bearing without guard board installer tool

Lower casing bracket and drive shaft oil seal installer tool

Lower casing bracket and drive shaft oil seal installer tool

Detection Device

Digital tachometer detection device

Digital tachometer

Digital circuit tester

Digital circuit tester and peak voltage adaptor

Peak voltage adaptor

Peak voltage adaptor detection device

Explosive Drawing and Symbol

Explosive Drawing

Explosive drawing legend with parts callouts and torque markings

  • 1 Parts explosive drawing
  • Oil, fluid sealant or locking substance daubing point
  • Screw specification and specified torque
  • Spare parts details

Symbol

Symbol legend for explosive drawings

Specifications

Outboard Engine Specifications

CategorySpecificationValue
DimensionOverall length717mm
DimensionOverall width361mm
DimensionOverall height (S)1029mm
DimensionOverall height (L)1156mm
WeightS24.5kg
WeightL25.5kg
PerformanceMax output2.9kW (4hp) @ 4500 r/min; 3.6kW (5hp) @ 5000 r/min
PerformanceFull throttle operation4000~5000 r/min
PerformanceMax fuel consumption1.6 L/h @ 5000 r/min
PerformanceIdle speed (Neutral)1500±50 r/min
Power UnitType4 stroke, OHV
Power UnitNumber of cylinders1
Power UnitDisplacement112 cm³
Power UnitBore × Stroke59mm × 41mm
Power UnitCompression ratio8.4
Power UnitCompression pressure660 kPa
Power UnitNumber of carburetor1
Power UnitControl systemTiller control
Power UnitStarting systemRecoil starter
Power UnitIgnition control systemT.C.I
Power UnitStarting enrichmentChoke valve
Power UnitSpark plugBPR7HS
Power UnitExhaust systemUnder water
Power UnitLubrication systemSplash lubrication
Fuel and OilFuel typeUnleaded regular gasoline
Fuel and OilFuel standardPON 86, RON 91
Fuel and OilFuel tank capacity1.3L
Fuel and OilRecommended engine oilAPI SE, SF, SE-SF, SG-CD SAE 10W30, 10W40
Fuel and OilEngine oil quantity0.5L
Fuel and OilRecommended gear oilHypoid gear oil SAE #90
Fuel and OilGear oil quantity100 mm³
BracketTilt angle4°, 8°, 12°, 16°, 20°
BracketTilt-up angle76°
BracketShallow water cruising angle30°, 42°, 54°
BracketSteering angle360°
Drive UnitGear positionsF-N-R
Drive UnitGear ratio2.08
Drive UnitGear typeBevel gear
Drive UnitPropeller directionClockwise
Drive UnitPropeller drive systemSpline

Maintenance Information

Power Unit

ItemSpecificationDetailValue
Cylinder HeadWarp limit0.1mm
CylinderBore59.00~59.02mm
CylinderWear limit59.1mm
CylinderTaper limit0.08mm
CylinderOut of round limit0.05mm
PistonPiston diameter58.950~58.965mm
PistonMeasuring point height10mm (from the bottom of piston)
PistonPiston-to-cylinder clearance0.035~0.065mm
PistonPin boss inside diameter13.009~13.017mm
Piston pinOutside diameter12.995~13.000mm
Piston ring (Top)Thickness1.5mm
Piston ring (Top)Breadth2.6mm
Piston ring (Top)End gap0.10~0.20mm
Piston ring (Top)Wear limit0.40mm
Piston ring (Top)Side clearance0.04~0.08mm
Piston ring (2nd)Thickness1.5mm
Piston ring (2nd)Breadth2.6mm
Piston ring (2nd)End gap0.25~0.40mm
Piston ring (2nd)Wear limit0.60mm
Piston ring (2nd)Side clearance0.02~0.06mm
Piston ring (Oil)Thickness2.5mm
Piston ring (Oil)Breadth2.6mm
Piston ring (Oil)End gap0.20~0.70mm
Piston ring (Oil)Wear limit0.90mm
ValveValve clearance (cold)Intake0.10±0.02mm
ValveValve clearance (cold)Exhaust0.10±0.02mm
ValveFace widthIntake1.84~2.26mm
ValveFace widthExhaust1.84~2.26mm
ValveSeat widthIntake0.6~0.8mm
ValveSeat widthExhaust0.6~0.8mm
ValveMarginIntake0.7mm
ValveMarginExhaust1.0mm
ValveHead diameterIntake23.9~24.1mm
ValveHead diameterExhaust21.9~22.1mm
ValveStem outside diameterIntake5.475~5.490mm
ValveStem outside diameterExhaust5.460~5.475mm
ValveGuide inside diameterIntake5.500~5.512mm
ValveStem-to-guide clearanceIntake0.010~0.037mm
ValveStem-to-guide clearanceExhaust0.025~0.052mm
Push rodRunout limit0.5mm
Valve springFree length35.0mm
Valve springFree length limit34.0mm
Connecting rodTilt limit1.2mm
Connecting rodSmall end inside diameter13.006~13.02mm
Connecting rodBig end oil clearance0.016~0.046mm
CrankshaftCrankshaft width64.4~64.5mm
CrankshaftBig end side clearance0.2~0.6mm
CrankshaftRound limit0.03mm

Continued:

ItemSpecificationDetailValue
CamshaftLobe heightIntake26.736~26.836mm
CamshaftLobe heightExhaust26.532~26.623mm
CamshaftRound diameter21.950~22.050mm
CamshaftJournal diameter14.966~14.984mm
CamshaftCamshaft round limit0.03mm
Valve lifterOutside diameter7.978~7.987mm
ThermostatValve opening temperature58~62℃
ThermostatFull-open temperature70℃
ThermostatValve lift3mm
Fuel pumpDischarge8 L/h
Fuel pumpPressure50 kPa
Fuel pumpPlunger stroke1.8~2.2mm

Ignition system

ItemDescription
Ignition timingBTDC 28°~32°
T.C.I system output peak voltage130V
T.C.I air gap0.4~0.6mm
Spark plug gap0.6~0.7mm
Ignitor ass'y resistance (Primary coil)0.7~0.96Ω
Ignitor ass'y resistance (Secondary coil)5.8~7.0KΩ

Tightening Torque

Specified torque

Part to be tightenedDetailPart nameThread sizeQuantityTorque
Oil drainBoltM8120 Nm
Spark plugM14125 Nm
Recoil starterBoltM638 Nm
Flywheel rotor ass'yNutM10144 Nm
CarburetorBoltM628 Nm
Intake manifoldBoltM628 Nm
Cylinder head coverBoltM6411 Nm
Cylinder head1st tighteningBoltM8415 Nm
Cylinder head2nd tighteningBoltM8430 Nm
1st tighteningBoltM616 Nm
2nd tighteningBoltM6111 Nm
Rocker arm screw boltBoltM6210 Nm
Locknut (rocker arm)NutM6×0.75210 Nm
Oil seal housingBoltM8118 Nm
Power unit mountingBoltM678 Nm
Thermostat coverBoltM638 Nm
Breather coverBoltM638 Nm
Crankcase1st tighteningBoltM8710 Nm
Crankcase2nd tightening722 Nm

Cont'd

Part to be tightenedDetailPart nameThread sizeQuantityTorque
Connecting rodBoltM7212 Nm
Oil splash gear unitBoltM618 Nm
Lower unit mounting1st tighteningBoltM623 Nm
Lower unit mounting2nd tighteningBoltM628 Nm
Lower unit housing cover1st tighteningBoltM626 Nm
Lower unit housing cover2nd tighteningBoltM6211 Nm
Anode1st tighteningBoltM613 Nm
Anode2nd tighteningBoltM618 Nm
Water pump housing1st tighteningBoltM643 Nm
Water pump housing2nd tighteningBoltM648 Nm
Water pump base1st tighteningBoltM613 Nm
Water pump base2nd tighteningBoltM618 Nm
Steering handle mountingBoltM8118 Nm
Shift lever bracketBoltM614.5 Nm
Bracket fixed cover1st tighteningBoltM623 Nm
Bracket fixed cover2nd tighteningBoltM628 Nm
Tilt lock plate1st tighteningNutM623 Nm
Tilt lock plate2nd tighteningNutM628 Nm
Swivel bracket1st tighteningNutM663 Nm
Swivel bracket2nd tighteningNutM668 Nm
Clamp bracketNutM8113 Nm
Ignitor ass'yBoltM628 Nm

General torque

Nut (a)Bolt (b)Torque
8mmM55Nm
10mmM68 Nm
12mmM818 Nm
14mmM1036 Nm
17mmM1243 Nm

General torque diagram showing nut and bolt dimensions

Periodic Service

Maintenance Timetable

ItemsContents10 hours (1 month)50 hours (3 months)100 hours (6 months)200 hours (1 year)
AnodeInspection/replacementOO
Spark plugCleaning/adjustment/replacementOOO
Grease pointsGreasingO
Bolts and nutsInspectionOO
Fuel tank and fuel lineInspectionO
Fuel filterInspection/replacementOOO
Fuel cockInspection/replacementOO
CarburetorInspection/replacementOO
Throttle cableInspection/replacementOO
Idling speedInspection/adjustmentOO
Start-in-gear protectionInspection/adjustmentOO
Engine oilReplacementOO
Valve clearanceInspection/adjustmentOO
Ignition timingInspectionOO
T.C.I air gapInspection/adjustmentOO
ThermostatInspectionO
Cooling water passageInspection/CleaningOO
Gear oilReplacementOO
Water pumpInspectionO
PropellerInspection/replacementOO

CAUTION: After running the outboard engine in saltwater,wastewater or mudwater,wash overthe enginebyfreshwaterimmediately.

If using leadedgasoline frequently,check thevalve and components each 100 hours.

Fuel System (Periodic)

  1. Check fuel tank,CARBURETOR,FUEL Check if fuel tank, carburetor, fuel pump and fuel pipe are damaged or leaked. Replace if necessary.

Check if the fuel filter on the tank is dirty.Clean dirt or replace it if necessary.

Fuel tank, carburetor, and fuel pipe inspection points

2. Check Fuel Cock and Fuel Joint: Check if fuel cock and fuel joint are cracked, damaged or leaking.

Replace if necessary.

Fuel cock and fuel joint inspection points

3. Check Fuel Filter: Check if fuel filter is cracked,damaged or has dirt inside. If so,replace it.

Fuel filter inspection with arrow mark direction

CAUTION: The arrow mark of the fuel filter must face toward the fuel pump. Clean the spilled oil.

Power Unit (Periodic)

Engine oil level

  • a)Remove oil levelplug,check engine oil level,ifbetween the following marks of theupper and lower.

Engine oil level plug and dipstick location

  1. Oil level plug2. Oil rule3. High position mark 4. Lowposition mark

Oil dipstick showing upper and lower level marks

  • b) If above the upper mark, drain the engine oil, if below lower mark, add engine oil up to upper mark.

CAUTION: Run the engine and then turn it off, wait for several minutes, and check the engine oil level by the oil rule again.

If the engine oil still notwithin the proper level, add/drain as needed.

Changing engine oil

  • 1.Remove oil level plug, drain plug with washer and gasket,drain off the engine oil.
  1. Install new gasket and washer, install drain plug.
  • 3.Fill engine oil into the crankcase through oil filler hole. Engine oil quantity: 0.5L Oil type:API SE,SF,SE-SF,SG-CD SAE 10W30,10W40
  1. Install oil level plug.
  • 5.Check engine oillevel.

Engine oil drain plug with washer and gasket

Engine oil fill through crankcase oil filler hole

CAUTION: Rotate the flywheel clockwise so that rocker arm is in free position, before adjusting valve clearance (Dead point position on compression stroke).

Valve clearance

  • 2.Remove cylinder head cover
  1. Use feeler gauge to measure the clearance between rocker arm and valve rod top: if out of specification, adjust.
  2. Remove spark plug cap and spark plug.

Valve clearance (cold position):

Inlet valve:0.10±0.02mm

Outlet valve: 0.10±0.02mm

Valve clearance measurement with feeler gauge on rocker arm

Spark plug

  • 2.Clean off carbon build-up on the electrodes.
  • 3.Check if the electrodes are corroded or have deposit, or if the washer is damaged. If necessary, change the spark plug. Spark plug type: BPR7HS
  1. Inspect if the spark plug gap is within specification. If necessary, change the spark plug.
  2. Install spark plug. Use spark plug spanner to tighten it according to specified torque. Specified torque: 25 Nm

Control System

Throttle grip

  • 1.Turn the throttle grip to fully closed position.
  • 2.Check if the throttle cable is slack and if the throttle lever touches the throttle stop screw.
  1. Loosen throttle cable stopper screw, adjust throttle cable position, and tighten throttle cable stop screw.

1.throttle cable stop screw

Throttle cable stop screw location

Idling speed

Check idling speed, and adjust it if necessary.

  • 1.Preheat engine for 5 minutes.
  • 2.Attach the tachometer to the spark plug wire to measure idling speed RPM.If out of specification, adjust it.
  • 3.Turn the throttle stop screw clockwise or counter clockwise, until the specified idling speed is attained.

Idling speed:1450~1550 r/min

Throttle stop screw for idling speed adjustment

NOTE: Turning clockwise to increase idling speed.

Turning counter clockwise to decrease idling speed.

CAUTION:

Start-in-gear protection

Set the shift lever in neutral, and check if the triangle marking of the detent aligns with the triangle marking of the starter.If necessary, adjust the adjusting nut on the tightw ire of the detent.

Start-in-gear protection triangle markings and adjusting nut

  1. Triangle marking 2. Adjusting nut 3. Tightwire ass'y, detent

Check gear oil level

Remove the oil level plug.If the gear oil overflows at the oil level checking hole, the oil volume added is correct; otherwise please add gear oil.

1.Oil level plug

Gear oil level plug on lower unit

Lower Unit (Periodic)

Changing gear oil

  • 1.Hold the outboard engine in an upright position.
  • 2.Place a containerunder the drain plug.
  • 3.Remove the drain plug,the oil level plug, and then drain the gear oil.
  • 4.Add gear oil through the drain plug using pressure filling device.
  • When gearoil overflows at theoillevel checkinghole,nstall theoillevel lug 5.
  • 6.Install the drain plug, then clean overflowing gear oil.

1.Oil level plug 2.Drain plug

Lower unit oil level plug and drain plug locations

NOTE: Check the drained gear oil.

Ifthe gear oil is millky, please check the oil seal. If necessary, replace the oil seal.

CAUTION: Must change drain plug washer each time.

  • 1.Inspect cooling water passage Ifblocked,clean it

Lower unit leakage check

Connecting the leakage tester to the oil level checking hole to check the lower unit leakage.If the pressure drops (pressure: 1kg/cm?), inspect the oil seal and comp onents.

General Inspection

Anode

Inspect lower unit anode and engine anode(on the therrmostat cover).Clean the greasy dirt and scales.If wear or damage is above 1/2,replace the anode.

CAUTION: Cannot grease or pa int the anode, or it will not operate properly.

Grease points

  • 1.Referthe illustration for greasing points, paint the water resistant grease.
  • 2.Paint anti-corrosion grease on the propeller shaft.

Grease points on outboard motor bracket assembly

Grease points on propeller shaft and lower unit

Cooling Water Passage

Cooling water passage inlet

Cooling water passage inlet location on lower unit

  • 2.Place the outboard engine in the water and ensure the water level is above the anti-vortex plate, then start the engine.
  • 3.Check if water overflows at the cooling water checking hole.If there is noflow or intermittent flow,check thecoolingwaterpassage.

1.Cooling water inlet

Cooling water inlet on anti-cavitation plate

  1. Cooling water checking hole

Cooling water checking hole on engine

Recoil Starter

NOTICE: When you service, please wear safety glasses and gloves.Please rermove spark plug cap and

Explosive Drawing

Recoil starter explosive drawing with numbered parts

SN.Part No.DescriptionQTYRemarks
1F4-04130000STARTER ASSY1
2F4-04130001CASE, STARTER1
3F4-04130012GUIDE, ROPE1
4F4-04130018SEAL, RUBBER1
5F4-04130101HANDLE, STARTER1
6F4-04130102COVER1
7F4-04130013MEATUS, START ROPE1
8F4-04130011WIRE, STARTER1
9F4-04130004SPRING, DRIVE2
10F4-04130003PAWL, DRIVE2

Recoil starter parts list continued with press plate and sheave drum

SN.Part No.DescriptionQTYRemarks
11F4-04130008BOLT, STARTER1
12F4-04130006PLATE, PRELL1
13F4-04130007SPRING, PLATE1
14F4-04130019DRUM, SHEAVE1
15F4-04130005SPRING, VOLUTE1
16F4-04130014WASHER, THRUST1
17F4-04130002BUSHING, STARTER CASING1
18F4-04130010WREST SPRING, DETENT1
19F4-04130009DETENT1
20GB/T97.1-85WASHER, THRUST3

Recoil starter mounting bolts and tightwire assembly

SN.Part No.DescriptionQTYRemarks
21GB/T5783-2000BOLT, HEXAGON M6×352
22GB/T5783-2000BOLT, HEXAGON M6×201
23F4-04000005FIXED PLATE, TIGHTWIRE1
24F4-02000013TIGHTWIRE ASSY, DETENT1
  1. Open the top cowling
  2. 2.Screw loosely the adjusting nut of the dent tightwire.
  3. 3.Remove thetightwirefrom thedetent.
  4. 4.Remove the starter fixing bolt, and remove the starter.
  5. Adjusting nut

Starter adjusting nut and detent tightwire location

Starter removal from power unit

Starter Rope Replacement

  1. Pull the starter rope out, and insert it in the notch of the sheave drum.T Turn the sheave drum clockwise until the volute spring is free.
  2. 2.Pull the starter rope completely.
  3. Remove the starter handle cover from the starter handle, and remove the starter rope. Untie the knot at the end of the starter rope.
  4. 4.Pull out the starter rope completely.
  5. 5.Insert the new starter rope into the starter assembly, and fix the rope onto the sheave drum and starter handle. At the end of the rope tie a knot as shown.

Starter rope knot tying diagram

Disassembling

Sheave drum disassembly with rope in notch

  1. Insert the start rope in the notch of the sheave drum and turn the sheave drum several rounds in counterclockwisedirection.
  2. Pull the starter handle many times to check if the sheave drum rotates stably. If necessary, repeat step 6 and step 7.

Disassembling and Inspection (Starter)

  1. Remove the start rope.
  2. Remove starter bolt, and remove press plate.
  3. Remove the sheave drum

WARNING: Uninstall the sheave drum carefully, to ensure that the volute spring does not pop out to hurt people.

  • 4.Remove the volute spring.
  1. Remove the detent and detent wrest spring.
  2. Inspect if the detent is cracked, worn or damaged. If necessary, replace it.
  3. Check if the drive pawl is cracked, worn or damaged. If necessary, replace it.
  4. Inspect if the drive spring is broken, cranked or damaged. If necessary, replace it.
  5. Check if the volute spring is broken, cranked or damaged. If necessary, replace it.

Volute spring removal from sheave drum

Detent and detent wrest spring parts

Drive pawl and drive spring inspection

Volute spring inspection for damage

Reverse the steps of disassembling.

  • 1.Put starter onto the power unit.
  • 2.Screw the hexagon bolt, and tighten it according to the specified torque.
  • 3.Install the detent tightwire.
  1. Adjust the adjustingnuton thetightwireof thedent,and align the trianglemarking of the dent with the triarigle marking of the starter case.
  2. Triangle mark
  • 2.Adjusting nut
  • 3.Detent tightwire

Triangle mark alignment on detent and starter case

Assembling and Installation (Starter)

Ignition System

NOTICE: When checking and repairing the ignition system, keep your hand, clothes, hair or personal belongings away from the rotating flywheel.

Check ignition coil on insulated working table, to prevent electricity leak and electroshock.

Don't touch the ignition coil or spark plug when the engine is running, to avoid electroshock. Keep the wires away from the rotating flywheel,to prevent the wire frombeing cut,or theinsulatinglayer of the wire from being worn.

When replacing fixing parts such as nuts and bolts, only parts from original manufacturer or parts made of same material and with strength can be used.Parts must be tightened according to the specified torques.

Explosive Drawing

Ignition system explosive drawing with flywheel and ignition coil

SN.Part No.DescriptionRemarks
1GB/T6171-86NUT, HEXAGON M10×1.25
2F4-04000021WASHER
3F4-04000020PULLEY, STARTER
4F4-04100000FLYWHEEL
5GB/T5782-2000BOLT M6×25
6F4-04000038IGNITION WINDING ASSY
7GB/T5783-2000BOLT M6×10
8GB/T97.1-85WASHER, PLATE 6
9F4-04000019HALF KEY

Wiring Diagram

Wiring diagram showing white and black wire connections

Wirebeamcolor:WWhite

B Black

Spark Plug Ignition

  1. Remove spark plug cap from spark plug. .
  2. Connect the ignition tester to the spark plug cap.
  3. 3.S Start the engine, and observe the sparks through the discharge window of the tester.

WARNING: Do not touch any joint part of the lead wire of the tester.

Keep away from inflammable gas or liquid, to prevent accident resulting from spark ignition.

Spark Plug Cap

  1. Remove the spark plug. Check if the spark plug cap is broken. Replace if necessary.
  2. Measure the resistance. If it's out of specification, replace. Spark plug cap resistance: 4.0~6.0k Ω
  3. Install the spark plug cap

Turn it clockwise until it is tight.

Flywheel Maintenance

  1. Use flywheel holder to remove the nut and starter pulley; use flywheel puller to remove flywheel.
  2. 2.Check if the flywheel is damaged or the permanent magnet part is firm. Replace if necessary.

Flywheel removal using flywheel holder and puller

Ignition Coil Inspection

  1. Ignition coil peak voltage
  2. 1 Remove spark plug cap.
  3. 2 Disconnect ignition coil tip (W).
  4. ③ Measure the ignition coil peak voltage output by a digital universal meter and a peak voltage adapter.If below specification, check the ignition coil.
  5. Ignition coil resistance
  6. ① Remove ignition coil and spark plug cap.
  7. 2 Measure ignition coil resistance.If out of specification, replace it.

Peakvoltageoutput:130V(1500r/min)

Digital universal meter

Ignition coil peak voltage measurement with digital universal meter

Resistance: 0.7~0.96 Q(Tester (+) pole: white wire; Tester (-) pole: black wire)

11.6~7.0k Q (Tester (+) pole: white wire; Tester (-) pole: high-voltage wire)

Peak voltage adapter

Ignition coil resistance measurement with peak voltage adapter

Fuel System

NOTICE: Gasoline is inflammable and highly volatile liquid. Its leakage can cause fire and explosion. Don't start the engine before all joints of the fuel system are connected or installed.When completing all maintenance steps, force short-time pressure to the fuel system to check for leakage.

Explosive Drawing

Fuel system explosive drawing showing fuel tank components

SN.Part No.DescriptionQTYRemarks
1F4-04120001TANK1
2F4-04120100TANK COVER ASSY1
3F4-04120103SPRING, PREVENT DESQUAMATING1
4F4-04120105ANTI-DESQUAMATION CLIP2
5F4-04120106EYELET, STEEL WIRE2
6F4-04120104CHAIN, PREVENT DESQUAMATING1
7F4-04120111GASKET, TANK COVER1
8GB/T5783-2000HEXAGON BOLT M6×251
9F4-04120002DAMPER, TANK3
10F4-04120003BUSH, DAMPER3

Fuel system parts list continued with fuel pipe clips

SN.Part No.DescriptionQTYRemarks
11F4-04000030CLIP, OIL PIPE "B"2
12F4-05000005PIPE, FUEL "A"1
13F4-04120005STRAINER, TANK1
14GB/T97.1-85WASHER, PLATE1

Fuel pump explosive drawing with components

SN.Part No.DescriptionQTYRemarks
1GB/T823-88SCREW, SMALL PAN HEAD M4×254
2F4-04090003COVER, FUEL PUMP1
3F4-04090004DIAPHRAGM, TOP1
4F4-04090011SCREW, VALVE M3×52
5F4-04090005PLATE (CHECK VALVE)2
6F4-04090002FUEL PUMP SHELL1
7F4-04090100DIAPHRAGM ASSY1
8GB/T309-2000ROLLER NEEDLE 3×121
9F4-04090008SPRING, DIAPHRAGM1
10F4-04090001SEAT, FUEL PUMP1

Fuel pump internal parts including plunger and diaphragm

SN.Part No.DescriptionQTYRemarks
11F4-04090007SPRING, PLUNGER1
12F4-04090006PLUNGER1
13GB/T6170-2000NUT M44
14F4-04090000FUEL PUMP ASSY1
15F4-04090009O-RING1
16F4-04000031-2CLIP, NYLON "B"1
17F4-04000028PIPE, FUEL "E"1
18F4-04000030SPRING, FUEL PIPE "B"9
19GB/T93-1987WASHER, SPRING 62
20GB/T97.1-85WASHER, PLATE 62

Fuel filter assembly and fuel line connections

SN.Part No.DescriptionQTYRemarks
21GB/T5783-2000HEXAGON BOLT M6×302
22F4-05000008PIPE, FUEL "D"1
23F4-05000300FUEL FILTER ASSY1
24F4-05000007PIPE, FUEL "C"1
25F15-05000011THREE THROUGH1
26F4-05000300FUEL PIPE TIE-IN ASSY1
27F4-05000006PIPE, FUEL "B"1
28F4-05000100OIL SWITCH1
29F4-05000010SPRING, OIL TUBE CLAMP1
30F4-05000005PIPE, FUEL "A"1

Carburetor and intake system assembly drawing

SN.Part No.DescriptionQTYRemarks
1GB/T5284-86HEXAGON BOLT M6×902
2GB/T97.1-85WASHER, PLATE 64
3F4-04110000SILENCER ASSY, INTAKE1
4JASO F404-96O-RING 2-24-0311
5F4-04000024GASKET, CARBURETOR AIRPROOF2
6F4-04000025GASKET, CARBURETOR1
7F4-04110006CLAMP, NYLON DENTIFORM1
8F4-04000035PIPE, RETURN GAS1
9F4-04000031-1CLAMP, NYLON "A"1
10F4-05000400CHOKE HANDLE ASSY1

Intake manifold and choke handle assembly parts

SN.Part No.DescriptionQTYRemarks
11F4-04000022GASKET, INNER PIPE1
12F4-04000025MANIFOLD, INTAKE1
13GB/T97.1-85HEXAGON BOLT M6×252
14F4-04000025CARBURETOR1

Fuel Tank Removal and Inspection

  1. Open the top cowling.
  2. 2.Remove three bolts fixing the starter.
  3. 3.Remove the starter. Pull thefuel tank out.
  4. 4.Remove the fuel pipe from fuel tank.
  5. Inspect the fuel tank and fuel tank cover for crack, leakage or damage. Replace if necessary.
  6. Inspect the tank strainer for dirt or clog. Clean or replace if necessary.

Fuel tank removal showing starter bolts and fuel pipe

Oil Switch Removal and Inspection

  • 1.Remove the fuel tank.
  • 2.Remove the bolts fixing the thumb wheel of the oil switch, and remove the thumb wheel.
  1. Oil switch 2. Thumb wheel 3. Plus pan head screw M4X12 4. Thumb wheel block
  • 3.Remove the bolts fixing the oil switch, and remove oil switch.
  • 1.Screw 2.Gasket 3. Oil switch 4.Bottom cowling
  1. Inspect the oil switch for leakage under prescribed pressure, replace if necessary. Prescribed air pressure: 0.1Mpa

Oil switch with thumb wheel and mounting screws

Oil switch removal showing gasket and bottom cowling

Oil switch pressure test setup

Fuel Joint Removal and Inspection

  • 1.Remove the bolts fixing the fuel joint.
  1. Remove the fuel joint.
  2. Inspect the fuel joint for crack or damage.
  3. Connect the fuel joint exit with a vacuum pressure gauge.
  4. Check whether the negative pressure can be maintained for over 10 minutes under the prescribed pressure. Replace if necessary. Prescribed pressure: 50kPa.

Fuel joint vacuum pressure gauge test

Fuel Pump Removal and Inspection

  • 1.Remove the bolts fixing the fuel pump.
  1. Remove the fuel pump.
  • 3.Connect the fuel pump intake with a vacuum pressure gauge.
  1. Block the exit of fuel pump with finger, and force a prescribed positive pressure to check for leakage.
  2. Force a prescribed negative pressure and check for leakage. Prescribed pressure:50kPa
  • 6.Connect the fuel pump exit with a vacuum pressure gauge.
  1. Force a prescribed negative pressure and check for leakage.Disassemble the fuel pump to check if necessary. Prescribed pressure: 50kPa
  • 8.Remove four bolts, and separate fuel pump cover from fuel pump seat.
  1. Remove the valve screw bolt from fuel pump, and remove the valve plate.
  2. Press the plunger and diaphragm, rotate the fuel pump seat, and align the notch with the notch on the plunger. Take the roller needle out.
  3. Inspect the diaphragm for crack and valve for damage. Replace if necessary.
  4. Reverse above step 8 to step 10 to install the fuel pump.

Prescribed pressure:50kPa

Fuel pump pressure test with vacuum gauge

Fuel pump disassembly showing cover, diaphragm, and valve plate

Intake System Removal and Inspection

  1. Loose throttle cable stop screw, and remove throttle cable.
  2. 2.Remove choke cable from carburetor.Remove choke cable.
  3. 3.Remove the bolt fixing air filter.
  4. 4.Remove air filter and carburetor.
  5. Remove intake manifold from engine.
  6. 6.Check if air filter and intake manifold are cracked or damaged.Replace it if necessary.

1.Throttle cable stop screw

Throttle cable stop screw location for intake system

Choke cable removal from carburetor

Air filter mounting bolt removal

Carburetor and intake manifold removal from engine

Power Unit

NOTICE: Before disassembling, disable the ignition system and turn off the ignition system. For example: remove the hang rope stopper from stop switch assembly, and remove spark plug cap from spark plug. n s e and os off the ignition system.For example: remove the hang rope stopper from stop switch assembly, and remove spark plug capfrom spark plug.

Explosive Drawing

Power unit explosive drawing showing cylinder head and gaskets

SN.Part No.DescriptionQTYRemarks
1GB/T5783-86HEXAGON BOLT M6×164
2F4-04000018COVER, CYLINDER HEAD1
3F4-04000017GASKET, CYLINDER COVER1
4F4-04080002PIPE, VALVE2
5F4-04080101CYLINDER HEAD1
6F4-04000003PIN, HOLLOW2
7F4-04000014GASKET, CYLINDER HEAD1
8GB/T5782-1986HEXAGON BOLT M6×451
9BPR7HSPLUG, SPARK1
10F4-04000033BOLT, CYLINDER HEAD "A"3

Power unit parts list continued with thermostat and bolts

SN.Part No.DescriptionQTYRemarks
11F4-04000034BOLT, CYLINDER HEAD "B"1
12GB/T5783-2000BOLT, HEXAGON M8×141
13GB/T97.1-85WASHER, PLATE 81
14F4-04000036THERMOSTAT1
15GB/T97.1-85WASHER, PLATE 68
16GB/T5783-2000BOLT, HEXAGON M6×203
17F4-04000012PIPE, RETURN1
18F4-04010002SPILE, WATER1
19F4-04070001COVER, THERMOSTAT1
20F4-04070100COVER AND SPILE WATER ASSY1

Thermostat cover and water spile assembly parts

SN.Part No.DescriptionQTYRemarks
21F4-04000011GASKET, THERMOSTAT1
22F4-04070000ANODE1
23GB/T818-85SCREW, PAN HEAD M5×251

Thermostat cover gasket and anode parts

SN.Part No.DescriptionQTYRemarks
1PS2700.03.02LIFTER, VALVE2
2F4-04000015ROD, VALVE PUSH1
3F4-04080009PLATE, PUSH ROD1
4PS2700.04.12BOLT, ROCKER ARM2
5PS2700.04.12ARM, VALVE ROCKER2
6PS2700.04.13PIVOT, ROCKER ARM2
7PS2700.04.18NUT, HEXAGON M6×0.751
8F4-04080005VALVE, INTAKE1
9F4-04080006VALVE, EXHAUST1
10F4-04080007SEAT, VALVE SPRING2

Valve train parts including valve lifters, rocker arms, and springs

SN.Part No.DescriptionQTYRemarks
11PS2700.04.03SEAL, VALVE STEM2
12F4-04080008SPRING, VALVE INNER2
13F4-04080010RETAINER, VALVE SPRING2
14F4-04080011CLAMP, VALVE2

Valve oil seal, spring, and retainer clamp parts

SN.Part No.DescriptionQTYRemarks
1F4-04010100CRANK CASE1
2F4-04010002PIPE, JOINT1
3F4-04010003OIL SEAL A25×40×51
4GB/T276-94BEARING 6205C31
5F4-04000009BREATHER GASKET1
6F4-04000010COVER, BREATHER1
7GB/T5782-2000HEXAGON BOLT M6×143
8GB/T97.1-85WASHER, PLATE 63
9GB/T818-85SCREW, PAN HEAD M4×61
10F4-04010003VALVE, BREATHER FLAP1

Crankcase parts with oil seal, bearings, and breather cover

SN.Part No.DescriptionQTYRemarks
11F4-04000003HOLLOW PIN Φ10×8.4×142
12F4-04050001COVER, CRANK CASE1
13F4-04000002CRANK CASE COMPLEX GASKET1
14GB/T5787-1986HEXAGON FLANGE BOLT M8×507
15F4-04060003OIL SEAL 20×30×7 (B)1
16F4-04060004OIL SEAL 10.8×21×72
17F4-04060002O-RING1
18F4-04060001SHELL, OIL SEAL1
19F4-04060000OIL SEAL SHELL ASSY1
20GB/T97.1-85WASHER, PLATE 88

Crankcase cover, oil seal housing, and oil splash gear parts

SN.Part No.DescriptionQTYRemarks
21GB/T5783-2000HEXAGON BOLT M8×201
22F4-04000006WASHER1
23F4-04050000GEAR UNIT ASSY1
24GB/T5783-2000BOLT, HEXAGON M6×121
25F4-04000008O-RING1
26F4-04000007PLUG WITH DIPSTICK1
27F4-04000001BOLT, DISCHARGING OIL1
28F4-04040000CAMSHAFT ASSY1

Piston, connecting rod, and crankshaft assembly parts

SN.Part No.DescriptionQTYRemarks
1F4-04020002PISTON RING 11
2F4-04020003PISTON RING 21
3F4-04020004COMBINED OIL RING1
4F4-04020006CIRCLIP2
5F4-04020005PIN, PISTON1
6F4-04020001PISTON1
7F4-04020100ROD, CONNECTING1
8F4-04020103BOLT, ROD CLEVEL2
9F4-04030000CRANK ASSY1
10F4-04000004WASHER, PLATE1

Camshaft decompressor assembly parts

Piston slider

Housing bearing installer

Piston slider and housing bearing installer tools

Space gauge

Space gauge for clearance measurement

Disassembling Power Unit from Outboard Engine

  • 1.Open the top cowling.
  • 2.Remove the starter and fuel pump.
  • 3.Remove choke cable and throttle cable.
  • 4.Removeairfilter andcarburetor.
  • 5.Remove bolts connecting the engine and upper casing.
  • 6.Carry the power unit and put it onto the working table.

Disassembling and Inspection (Power Unit)

Special Tools

Bearing puller special tool for power unit

Bearing puller

Oil seal installer tool for power unit

Oilsealinstallertool

Valve spring compressor

Valve spring compressor tool for power unit

Housing oil seal installer

Housing oil seal installer tool for power unit

Cylinder Cover

Disassembling

    1. Remove the bolts of cylinder head cover.
  • 2.Remove the bolts of the cylinder cover according to the reverse numbering sequence of the cylinder cover.
  • 3.Remove the crankcase cover.Remove the valve push rod
  • 4.Remove the rocker arm pivot, rocker arm, rocker arm shaft and push rod plate.

Push rod

Cylinder cover bolt removal sequence and push rod location

Inspect valve push rod runout.Replace if exceeding the specified value. Valve push rod runout limit: 0.5mm

Valve push rod runout measurement setup

Valve and valve pipe

  • 1.Inspect the valve seat width. If not in the prescribed range,repair the valve seat. Valve seatwidth:0.6~0.8mm
  • 2.Inspect the valve margin thickness (T).If not as in the prescribed value,replace the valve. The margin thickness of valve: T
  • 3.Inspect the valve stem diameter.If not in the prescribed range, replace the valve. The diameter of valve stem:

Intake door:0.7mm

Exhaust door:1.00mm

Valve seat width and margin thickness inspection diagram

Intake:5.475~5.490mm

Exhaustvalve:5.460~5.475mm

  • 4.Measure the valve stem runout.If exceeding the limit, replace the valve. Valve stem runout limit:0.03mm
  • 5.Measure the inner diameter of the valve pipe. Theinner diameter of thevalve pipe: 5.500~5.512mm

Valve stem diameter and valve pipe inner diameter measurement

CAUTION: When replacing the valve, please use the new valve pipe and valve oil seal.

Valve spring

  1. Measure the free length of valve spring. If less than prescribed value, replace. The minimum free length: 34mm
  2. 2.Measure the valve spring tilt. If exceeding the prescribed limit, replace.

The maximum tilt limit: 1.2mm

  • 1.Clean the carbon on the valve.
  • 2.Coat a thin layer of bluing dye evenly onto the seal face of the valve seat.
  • 3.Lap the valve on valve seat by valve lapping tool.
  • 4.Measure thevalveseatwidth. The valve face is with bluing dye. If the valve and valve seat do not match, or the valve seat width does not conform to specified value,reface and lap thevalve seat.

If the contact surface is not even, replace the valve pipe.

Valve rocker arm

Check the rocker arm for crack, perforation or damage.Replace if necessary.

Valve pipe replacement

  • 1.Knock out the valve pipe from the direction of combustion room.
  • 2.Knock in the new valve pipe from the direction of the top of cylinder cover. NOTE:

Coat the oil on the surface of pipe before installation.

  • 3.Bore the inner diameter of pipe to the prescribed value by reamer.

Inner diameter of valve pipe: 5.500~5.512mm

NOTE: When taking out the reamer, don't rotate it in counter clockwise direction.

Valve seat inspection

Thevalveseatwidth:

0.6~0.8mm

Themaximumvalveseatwidth:

1.1mm

Valve seat cutting

  • 1.Use 45° cutter to adjust the valve seat width. Turn the cutter clockwise until the valve seat face is smooth.
  • 2.If the valve seat is centered on the valve face but it's too wide,to reduce the valve seat width, use 30° cutter to adjust the top edge of the seat, and use 60° cutter to adjust the bottom edge of the seat.
  • 3.If the valve seat is too narrow and on the top edge of valve surface, use 30°cutter to adjust the top margin of the seat, and use 45° cutter to adjust the valve seat width if necessary.
  • 4.If the valve seal surface is too narrow and on the bottom edge of valve surface,use 60°cutter to adjust the bottom edge of the seat, and use 45° cutter to adjust the valve seat width if necessary.
  • 5.Coat evenly a thin layer of lapping compound onto valve seat, and lap the valve by lapping tool.
  1. Clean up the remaining lapping compound.
  • 7.Inspect again the valve seat width.

Valve seat cutting using 45-degree cutter

Valve seat adjustment with 30-degree and 60-degree cutters

Valve lapping with lapping compound and tool

CAUTION: Do not overlap the valve.Turn the lapping tool evenly with a downward force of 40~50N. Do not contaminate push rod and valve pipe with lapping compound.

Thermostat

  • 1.Remove thermostat cover and thermostat.
  • 2.Suspend thermostatin the containerwithwater.
  • 3.Heat the container.
  1. Inspect valve lift situation in the prescribed water temperature. If out of specification, replace.
  • 5.Install thermostat and thermostat cover.Tighten the bolts to specified torque.
Water temperatureThe lift height
58~62℃0.05mmvalvelift
Over 70℃Over 3mm

Crankcase

Disassembling:

  • 1.Remove the bolts according to the reverse numbering sequence of the crankcase cover.
  • 2.Remove the cover of crankcase.
  1. Remove the camshaft and valve lifter.
  2. Remove the connecting rod bolt and connecting rod cap,and remove connecting rod and piston assembly.
  3. Use clipper to remove circlip, and remove piston pin and piston.
  • 6.Remove crankcase and crankcase gasket.
  1. Remove oil splasher gear assembly.
  • 8.Removebreathercover bolts,and remove breather cover.
  • 9.Remove valve bolts and remove valve.
  • 10.Remove oil seal shell bolts, and remove oil seal shell and oil seal.

Breather

  1. Inspect breather flap valve, if damaged/cranked/cracked, replace.
  2. 2.Inspect breather hole. If clogged, clean.
  3. Inspect breather return pipe. If cracked/leaked/damaged, replace.

Piston

Measure piston outside diameter at the specified measuring point. If out of specification, replace.

Pistondiameter:58.950~58.965mm

Measuring point@: 10mm

Piston diameter measurement at specified measuring point

Piston-to-cylinder clearance measurement diagram

Cylinder bore

  1. Measure cylinder bore separately at measuring point ①, O, ③. At each point, measure the cylinder bore at places D1, D3, D5 parallel to the crankcase and at places D2, D4,D6 vertical to the crankshaft.

Measuring point height:

①100mm;

②40mm;

③70mm

Cylinder bore:

59~59.02mm

59.10mm

Limit size:

  1. Calculate taper limit and round limit. If out of specification, replace crankcase.

Taper limit: 0.08mm(D1-D5, D2-D6)

Round limit: 0.05mm(D2-D1, D6-D5)

Piston pin diameter

Measure piston pin outside diameter. If out of specification, replace the piston pin. Piston pin outside diameter:12.995~13.000mm

Piston ring

  • 1.Push the piston ring parallel with the piston crown into the specified measuring point of the cylinder (1omm from conjunction surface).
  • 2.Measure end gap by space gauge. If out of specification, replace the piston ring.

End gap (installed) / limit size:

Top ring 0.10~0.20mnm/0.4mm

2nd ring 0.25~0.40mm/0.6mm

Oil ring0.2~0.7mm/0.9mm

  1. Install piston ring to piston, and measure side clearance between piston ring and its slot by clearance gauge. If out of specification, replace the piston ring.

Side clearance:

Top ring 0.04~0.08mnm

2nd ring 0.02~0.06mm

Camshaft decompressor

  • 1.Inspect camshaft decompressor, gear, and weight.If gear is worn/damaged/cracked, replace.

If weight is unsmoothly moving, replace.

  • 2.Measure camshaft lobe diameter@ and height .If out of specification, replace it.

Camshaft lobe diameter and height measurement points

@Intake camshaft:21.950~22.050mm

Exhaust camshaft:21.950~22.050mm

b

  • ?

Intake camshaft:26.736~26.836mm

Exhaustcamshaft:26.532~26.623mm

  • 3.Measure camshaft diameter. If out of specification, replace the camshaft.

a

Camshaft journal wear limit:14.934mm

Crankshaft

Measure crankshaft runout.If out of specification, replace.

Crankshaft runout measurement setup

Crankshaft runout limit: 0.03mm

Oil clearance

  1. Put a piece of plastic space gauge on to the crankpin in parallel to the crankshaft.
  2. Assemble the connecting rod to the crankpin.
  3. 3.Tighten the connecting rod bolts to the specified torque.

12Nm

Tightening torque:

  1. Remove the connecting rod, measure the compressed width of the plastic space gauge. If out of specification, replace the connecting rod.

Oil clearance:

0.020~0.052mm

Note:

Don't rotate the connecting rod before completing measurement.

Valve lifter

  • 1.Inspect valve lifter for wear or damage. Replace if necessary.
  • 2.Measure valve lifter outside diameter. If out of specification, replace the valve lifter.

Valvelifter outside diameter:7.9650mm

Oil splash gear

Oil splash gear unit inspection

Inspect oil splash gear unit, if slow-moving/wear/damage/crack, replace.

Crankshaft bearing

Inspect bearing, if pitting/rumbling, replace.

NOTE: Don't remove bearing unless you replace it.

Oil seal housing

  1. Inspect oil seal housing for crack/damage. Replace if necessary.
  2. Inspect O-ring for crack/damage. Replace if necessary.

Crankcase and crankcase cover

  1. Inspect crankcase cover.If cracked/damaged, replace.
  2. Inspect cooling water passage for dirt or clog.Clean if necessary.

Full Installation

Piston connecting rod installation

Install piston, connecting rod, piston pin and piston pin circlip.

NOTE: When installing, make sure that the mark on the connecting rod is at the same side of the mark on the piston crown.

Use new piston pin circlip. Make sure that circlip gap is not aligned with the circlip slot gap.

Piston connecting rod installation with mark alignment

Piston ring installation

  • Install oil ring, 2nd ring and top ring. NOTE: Make sure that the mark is toward the piston crown when installing the 2nd ring.
  • Picture of the piston ring gap Oil ring end gap 1 (lower rail) Oil ring end gap 2 (expanded ring) Oil ring end gap 3 (upper rail) 2nd piston ring end gap 4

Top piston ring end gap 5

Piston ring gap positioning diagram

Piston installation

Use piston slider to install piston, and make sure the piston crown Up"is toward the flywheel side.

Piston installation using piston slider with UP mark toward flywheel

NOTE: Apply motor oil to the piston and piston ring side when installing.

Oil seal housing installation

  1. Install oil seals 10.8x21x7 (2 pieces) by oil seal installer tool.
  2. 2.Install oil seals B20 X 30 X 7 by oil seal installer tool.

NOTE:

  • ① Apply grease onto new seal before installation.
  • ② Make sure the oil seal direction as shown.

Crankshaft installation

  1. Install the crankshaft bearing to crankcase by special tools (if change bearing). Install oil seal.

Crankshaft bearing installation with special tool

Housing oil seal installer

Oil seal installing direction diagram

Oil seal installing direction

Housing oil seal installer tool in use

Housing bearing installer

Housing bearing installer tool in use

NOTE: Fit the bearing with its manufacturer's mark toward the direction of the flywheel side.Apply motor oil to the new oil seal installing.

  1. Install crankshaft to crankshaft case.
  2. Install connecting rod cover, and tighten the connecting rod bolt to the specified torque. Specified torque: 12 Nm

NOTE: Apply motor oil to moving parts before installing.

Camshaft installation

Install camshaft. Make sure that the camshaft gear mark is aligned with the camshaft timing gear mark.

NOTE: Apply motor oil to moving parts before installing.

NOTE: Apply motor oil to moving parts before installing.

Camshaft gear and timing gear mark alignment

Upper Unit

Top Cowling

Explosive Drawing

Crankcase cover installation

  1. Install oil seal housing.
  2. 2 Install oil splasher gear assembly.
  3. 3 Install crankcase cover, and tighten the bolts twice as shown.

Tightening torque:

1st 10 Nm

2nd 22 Nm

Crankcase cover bolt tightening sequence

SN.Part No.DescriptionQTYRemarks
1F4-06000000TOP COWLING ASSY1
2GB/T8.8-2000SCREW, PAN HEAD M5×122
3F4-06000005HOOK, LOCK1
4F4-06000002BAR RUBBER, AIRPROOF1
5GB/T845-85SCREW, TAPPING ST5.5×194
6F4-06000003COVER, TOP COWLING MUFFLING1
7F15-08000004POTHOOK1
8F4-06000001TOP COWLING1
9GB/T818-2000SCREW, PAN HEAD M5×202
10GB/T6172.1-2000THIN NUT, HEXAGON M52

Top cowling parts list with lock hook and rubber underlay

SN.Part No.DescriptionQTYRemarks
11F4-06000006UNDERLAY, POTHOOK1
12F4-06000004UNDERLAY, RUBBER4

Disassembling and inspection

  1. Remove airproof rubber bar.
  2. Remove top cowling muffling cover bolt and rubber underlay.
  3. Remove top cowling muffling cover.
  4. Remove lock hook and pothook.
  5. Inspect if top cowling is cracked or damaged. Replace it if necessary.
  6. Inspect if airproof rubber bar is cracked or damaged.Replace it if necessary.
  7. Inspect if top cowling muffling cover is cracked or damaged.Replace it if necessary.
  8. Inspect if lock hook and pothook is cracked, deformed or damaged. Replace it if necessary.

Bottom Cowling

Explosive drawing

Bottom cowling explosive drawing with handle and clamp lever

Bottom cowling parts continued with bolts and covers

SN.Part No.DescriptionQTYRemarks
1F4-05000001COWLING, BOTTOM1
2GB/T818-2000CROSS PAN HEAD BOLT M6×142
3F4-05000016HANDLE1
4GB/T818-2000CROSS PAN HEAD BOLT M6×122
5GB/T5783-86BOLT M6×121
6F15-05030000LEVER, CLAMP1
7F15-05000022BUSH A1
8F15-05000023WASHER, WAVE1
9F15-05000036BUSH B1
10F4-05000012LEVER, CLAMP1

Bottom cowling rubber cover and clamp lever parts

SN.Part No.DescriptionQTYRemarks
11F4-05000013-2COVER, RUBBER B1
12GB/T6170-86NUT, HEXAGON M61
13GB/T5783-2000BOLT, HEXAGON M6×251
14GB/T97.1-85WASHER, PLATE 612
15GB/T5783-2000BOLT, HEXAGON M6×147

Disassembling and inspection

  1. Remove rubber coverB.
  2. Remove handle bolt and handle.
  3. Remove top cowling clamp lever bolt and clamp lever.
  4. Removetopcowling clampleverbushA and clampleverbushB.
  5. Removewavewasher.
  6. Inspect if bottom cowling is cracked or damaged. Replace if necessary.
  7. Inspect if clamp lever handle is cracked or damaged.Replace if necessary.
  8. Inspect if clamp lever is cracked or damaged.Replace if necessary.
  9. Inspect ifwave washer and clampleverbush are cracked or damaged.Replace if necessary.

Steering Handle

Explosive drawing

Steering handle explosive drawing with bushings and damper

SN.Part No.DescriptionQTYRemarks
1F4-01090001HANDLE, STEERING1
2F4-01000009BUSHING, HANDLE1
3F4-01000012BUSH, WAVE WASHER1
4F4-01000010WASHER, BUSHING2
5F4-05000014BUSHING, RUBBER1
6F4-01000011WASHER, BUSHING1
7F4-01000008BUSHING1
8F4-01000014COVER, HANDLE STEERING1
9GB/T5783-2000BOLT M8×251
10GB/T91-86PIN, COTTER 1.6×121

Steering handle friction adjusting bolt and throttle grip parts

SN.Part No.DescriptionQTYRemarks
11F4-01090200BOLT, FRICTION ADJUSTING1
12F4-01090006BUSH1
13F4-01090007SPRING, COMPRESSION1
14GB/T848-85WASHER, PLATE1
15F4-01090303INDICATOR, THROTTLE1
16F4-01090301GRIP, STEERING HANDLE1
17F4-01090302RUBBER, HANDLE1
18GB/T820-85SCREW M5×241
19GB/T827-86RIVET 2×51
20F4-01090300STEERING HANDLE ASSY1

Steering handle throttle lever, cable, and stop switch parts

SN.Part No.DescriptionQTYRemarks
21F4-01090003FRICTION1
22F4-01090100LEVER, THROTTLE1
23GB/T818-85SCREW, PAN HEAD M5×122
24F4-01090002STAY1
25F4-01090008THROTTLE CABLE ASSY1
26F4-01090401STOPPER, HANG ROPE ASSY1
27F4-01090400ENGINE STOP SWITCH ASSY1

Disassembling and inspection

  1. Remove steering handle cover.
  2. Remove handle bush, bush washer and wave washer.
  3. Remove steering handle shocker damper.
  4. Remove cotter pin and friction adjusting bolt
  5. Remove steering handle.
  6. Remove throttle cable.
  7. Removethrottleleverstayand throttlelever.
  8. Remove engine stop switch.
  9. Inspect if steering handle is cracked or damaged. Replace if necessary.
  10. necessary.
  11. Inspect if steering handle shock damper is cracked or damaged. Replace if necessary.
  12. Inspect if throttle cable is cracked or damaged. Replace if necessary.
  13. Inspect the conduction of engine stop switch. If not to specification, replace it.

Steering handle cover removal and bush inspection

Throttle cable and throttle lever removal

Engine stop switch conduction test diagram

Remove lockplate:

Conducting Not conducting

Install lockplate:

Push stop switch button: Conducting

Bracket

Explosive drawing

Bracket explosive drawing with shock absorption and swivel parts

SN.Part No.DescriptionQTYRemarks
1F4-02000008BUSH, SHOCK ABSORPTION4
2F4-02000007TOP, SHOCK ABSORPTION1
3F4-02020000UPPER LOCKING RING ASSY1
4F4-01050002SPRING, CONICAL1
5F4-01050000TILT ROD ASSY1
6GB/T889.1-2000NUT M81
7F4-01000002PLATE2
8F4-01030001BRACKET, SWIVEL1
9GB/T6170-86HEXAGON NUT M61
10GB/T97.1-85WASHER11

Bracket parts continued with tilt lock and torsion springs

SN.Part No.DescriptionQTYRemarks
11F4-01000003WASHER, NYLON2
12F4-01030003SPRING, TORSION (LEFT)1
13F4-01030002BUSHING, NYLON2
14GB/T5783-2000HEXAGON BOLT M6×202
15F4-01030005FIXED COVER, BRACKET1
16F4-01030103SHEATH, HANDLE2
17F4-01030004SPRING, TORSION (RIGHT)1
18F4-01030100BRACKET, TILT LOCK1
19F4-01000006SPRING1
20F4-01000007SPRING1

Bracket tilt locked clasp and clamp handle parts

SN.Part No.DescriptionQTYRemarks
21GB/T5783-2000HEXAGON BOLT M6×122
22F4-01070000TILT LOCKED CLASP ASSY1
23F4-02000009BOTTOM ABSORPTION ASSY1
24F4-01000004BUSHING, BOLT1
25F4-01010005RIVET, CLAMP HANDLE2
26F4-01010004CLAMP SHIPBOARD HANDLE2
27F4-01010002CLAMP BOLT2
28F4-01010003CLAMP PLATE2
29GB/T5782-2000HEXAGON BOLT M6×1201
30GB/T5782-2000HEXAGON BOLT M8×1351

Bracket clamp bracket, swivel cover, and locked screw parts

SN.Part No.DescriptionQTYRemarks
31F4-01010001BRACKET, CLAMP (RIGHT)1
32F4-01000005COVER, SWIVEL BRACKET1
33GB/T5782-86HEXAGON BOLT M6×356
34F4-01060002CLAMP HANDLE1
35GB/T875-86RIVET 4×111
36F4-01060001LOCKED SCREW1
37GB/T96-1985BIG WASHER2
38F4-01020000BRACKET, LEFT ASSY1
  • 1.Remove tilt locked clasp.
  1. Remove swivel bracket cover.
  • 3.Remove bottom shock absorption assembly and shock absorption bush.

Disassembling and inspection

Remove clamp bracket.

  • 5..Removeswivelbracket.
  • 6.Remove bracket fixed cover, and the tilt lock bracket.
  1. Inspect the the swivel bracket and clamp bracket for damage or crack. Replace if necessary.
  • 8.Inspect the bush and shock absorption for damage or crack.Replace if necessary.
  • 9.Inspect:whether the tilt lockbracket and tilt locked clasp were distorted,replace if needed.

Tilt locked clasp and swivel bracket cover removal

Clamp bracket removal from swivel bracket

Tilt lock bracket and fixed cover inspection

Upper Unit Casing

Explosive drawing

Upper unit casing explosive drawing with shift handle and rods

SN.Part No.DescriptionQTYRemarks
1F4-00000007HANDLE, GEAR SHIFT1
2F4-02010000SHAFT, CHANGE1
3JISB2401O-RING P92
4F4-02000002BUSHING, SHIFT ROD LEVER1
5GB/T820-2000SCREW, OVAL HEAD M5×201
6F4-02000003SPRING, GEAR1
7GB308-84BALL 81
8GB/T5783-2000BOLT M5×251
9GB/T308-84PIN, COTTER 1.6×121
10GB/T97.1WASHER, PLATE 52

Upper unit parts continued with shift rod lever and connectors

SN.Part No.DescriptionQTYRemarks
11F4-02000006LEVER, SHIFT ROD1
12F4-02000004ROD, SHIFT1
13F4-00000003CONNECTOR, SHIFT ROD A1
14F4-00000004CONNECTOR, SHIFT ROD B1
15F4-00000005BIG WASHER1
16GB/T5284-86BOLT M6×201
17F4-00000001PIN, HOLLOW4Type S: 2
18JB/T7940.1-95GREASE CUP M61
19GB/T97.1-85WASHER7
20GB/T5284-86HEXAGON BOLT M6×357

Upper unit casing, water tube, and extension parts

SN.Part No.DescriptionQTYRemarks
21F4-02000011WASHER, SHIFT ROD1
22F4-02000001CASING, UPPER1
23F4-02000012RUBBER PLUG, UPPER2
24F4-02040002I-SHAPED RUBBER BAND1
25F4-02040000WATER TUBE1Type S: F4-02040000S
26F4-02030001EXTENSION1L
27GB/T 893.1-1986CIRCLIP 221L
28F4-02030003RUBBER BUSHING1L
29F4-02030002BUSHING, DRIVE SHAFT1L
30F4-00000006GASKET, ENGINE1

Disassembling and inspection

    1. Remove the water tube.
  • 2.Remove the gear shift handle and change shaft.
  • 3.Remove the shift rod and shift rod lever.
  • 4.Check upper casing and extension for crack or wear. Replace if necessary.
  • 5.Check gear shift handle and change shaft for crack or wear. Peplace if necessary.

Water tube and gear shift handle removal

Shift rod and shift rod lever removal from upper casing

Upper casing and extension inspection for cracks

Lower Unit

Water Pump Assembly

Explosive drawing

Water pump assembly explosive drawing with impeller and housing

SN.Part No.DescriptionQTYRemarks
1GB/T5782-2000HEXAGON BOLT M6×454
2F4-03000020PLATE, WATER PUMP FIXED2
3F4-03000021RUBBER TUBE, WATER PUMP1
4F4-03000013PIN, WATER PUMP2
5F4-03000019HOUSING, WATER PUMP1
6F4-03000018GASKET, WATER PUMP COVER1
7F4-03000017COVER, INNER WATER PUMP1
8F4-03060000IMPELLER, WATER PUMP1
9F4-03000015OUT PLATE1
10F4-03000014RUBBER JACKET, SHIFT ROD1

Water pump base, gasket, and mounting bolt parts

SN.Part No.DescriptionQTYRemarks
11GB/T5783-2000HEXAGON BOLT M6×251
12GB/T97.1-85WASHER, PLATE5
13F4-03000012BASE, WATER PUMP1
14F4-03000011HERMETIC GASKET1

Disassembling and inspection

    1. Remove water pump fixed plate.
  1. Remove water pump housing.
  2. Remove water pump impeller and inner water pump cover.
  • 4.Remove water pump base.
  • 5.Check water pump housing and out plate for crack, crank or damage. Replace if necessary.
  1. Check inner water pump cover and impeller for crack, deform, burn or damage. Replace if necessary.
  2. Check water pump base for crack, crank, scratch or damage. Replace if necessary.

Water pump fixed plate and housing removal

Water pump impeller and inner cover removal

Water pump base removal and inspection

Water pump components inspection for damage

Lower Unit Gear Assembly

Explosive Drawing

Lower unit gear assembly explosive drawing with propeller and gears

SN.Part No.DescriptionQTYRemarks
1GB/T91-86PIN, COTTER 2.5×301
2F4-03080000NUT ASSY1
3F4-03000026WASHER1
4F4-03070000PROPELLER ASSY1
5F4-03000025SPACER1
6F4-03000022ANODE1
7GB/T97.1-85WASHER, PLATE1
8GB/T861.1-87WASHER, INTERNAL TOOTH1
9GB/T5783-2000HEXAGON BOLT M6×121
10F4-00000001HOLLOW PIN2

Lower unit parts continued with oil seals and bearings

SN.Part No.DescriptionQTYRemarks
11F4-03000027OIL SEAL 10.8×21×72
12F4-03000009WASHER, REVERSE GEAR2
13F4-03040000REVERSE GEAR ASSY1
14GB/T276-94BEARING 6004C22
15F4-03050002OIL SEAL 13×22×72
16JISB2401 P48O-RING1
17F4-03050001COVER, LOWER CASING1
18GB/T97.1-85WASHER, PLATE5
19GB/T5783-2000HEXAGON BOLT M6×182
20F4-03000003BEARING1

Lower unit casing, barrel bearing, and gear parts

SN.Part No.DescriptionQTYRemarks
21F4-03000023PLUG, OIL HOLE3
22F4-03000024GASKET3
23F4-03000001LOWER CASING1
24GB/T-896-86CIRCLIP1
25F4-03000007INITIATIVE GEAR1
26F4-03000006WASHER, INITIATIVE GEAR1
27F4-03000002BEARING1
28F4-03000008PLUNGER, SHIFT1
29F4-03010000POSITIVE GEAR ASSY1
30F4-03030002CLUTCH BLOCK1

Lower unit clutch block, propeller shaft, and drive shaft parts

SN.Part No.DescriptionQTYRemarks
31F4-03000003SPRING, CLUTCH BLOCK1
32F4-03030001SHAFT, PROPELLER1
33F4-03000004SHAFT, DRIVE1L
F4-03000004SSHAFT, DRIVE1S
34F4-03000016PIN2
35F4-03000005CLIP1
36GB/T5782-2000HEXAGON BOLT M6×1672L
GB/T5782-2000HEXAGON BOLT M6×402S
37F4-03020000CAM ASSY, SHIFT ROD1L
F4-03020000SCAM ASSY, SHIFT ROD1S

Disassembling and inspection

    1. Remove cotter pin and nut assy.
  1. Remove propeller assembly and spacer.
  • 3.Remove the lower casing cover.
  1. Remove the reverse gear assy, drive shaft, positive gear assy, and shift pluger.
  2. 5.Remove shift rod cam assy and drive shaft.
  3. 6.Remove barrel bearing with guard board (F4-03000002).
  4. Remove barrel bearing without guard board (F4-03000003) by using barrel bearing installer tool.
  5. Remove the clutch block from the propeller shaft.

Propeller shaft and clutch block

  1. Check clutch block for wear or damage. Replace if necessary.
  2. Check propeller shaft for wear or damage. Replace if necessary.

Clutch block installation

  1. Put clutch block spring into the hole of the propeller shaft tail.
  2. 2.Install the clutch block as shown.Take note ofthe direction.

Clutch block installation direction on propeller shaft

Lower casing cover

  • 1.Check bearing for rust or rumbling when run.Replace if necessarary.
  1. Remove bearing and oil seal by bearing puller. Note: Don't remove bearing unless change it.
  2. Clean casing cover by a soft brush and solvent.
  • 4.Check casing cover for crack or damage. Replace if necessary.

Lower casing cover oil seal and bearing installation

  • 1.Install oil seal.
  1. Install bearing.

Note: Please use special tool to install oil seal and bearing. Pay attention to the oil seal installation direction and installation depth. Make sure the manufacturer mark faces toward the reverse gear.

Lower casing cover oil seal installation with special tool

Lower casing cover bearing installation with special tool

Barrel bearing

Inspect barrel bearing with guard board and barrel bearing without guard board for wear, crack or damage.Replace if necessary.

Drive shaft

Inspect the drive shaft for crank or wear.Replace if necessary.

Gear

Forward gear bearing

Inspect bearing forrust and rumbling when rotating.Replace if necessary.

Lower unit casing

  • Replace if necessary.
  • 2.Install the barrel bearingwith guard board and barrel bearing without guard board by special tool.

Barrel bearing with guard board installer tool in use

Barrel bearing with guard board installer tool

Lower casing bracket and barrel bearing without guard board installer tool

Lower casing bracket and barrel bearing installer tool in use

  • 3.Install new oil seal, with the depth as shown. (unit: mm)

Drive shaft oil seal installation depth diagram

Lower casing bracket and drive shaft oil seal installer tool

Lower casing bracket and drive shaft oil seal installer tool in use

Trouble typePossible reasonRecovery action
Starter not operateStarterRepair or replace
Starter not operateShift level is notin neutralShift toneutral
Engine will not start (starter operates)Fuel tank is emptyFill tankwith clean,freshfuel
Engine will not start (starter operates)Fuel filter cloggedReplace fuel filter
Engine will not start (starter operates)Fuel pump has malfunctionedRepair or replace
Engine will not start (starter operates)Air vent screwnot loosenedLoosen airvent screw
Engine will not start (starter operates)Spark plug(s) fouled or of incorrect type.Inspect spark plug(s). Clean orreplace withrecommended type
Engine will not start (starter operates)Spark plug cap(s) fitted incorrectlyCheck and re-fit cap(s)
Engine will not start (starter operates)Ignition wiring damaged or poorly connectedCheck wires for wear or breaks.Tighten all loose connections.Replace worn or broken wires
Engine will not start (starter operates)Ignition parts are faultyReplace
Engine will not start (starter operates)Engine stop switch lanyard is not attachedAttach lanyard
Engine will not start (starter operates)Engine inner parts are damagedRepair
Engine idles irregularly or stallsSpark plug(s) fouled or of incorrect type.Inspect spark plug(s).Clean or replace withrecommended type
Engine idles irregularly or stallsFuel system is obstructedCheckfor pinched orkinkedfuel line or other obstructions in fuel system
Engine idles irregularly or stallsFuel contaminated orstaleFill tank with clean,freshfuel
Engine idles irregularly or stallsFuel filter cloggedReplace with recommended type
Engine idles irregularly or stallsSpark plug gap is incorrectInspect and adjust as specified
Engine idles irregularly or stallsIgnition wiring damaged or poorly connectedCheck wires for wear orbreaks. Tighten all loose connections.Replaceworn orbroken wires
Engine idles irregularly or stallsSpecified engine oil is not being usedCheck and replace oil as specified
Engine idles irregularly or stallsThermostat is faulty or cloggedReplace
Engine idles irregularly or stallsCarburetor adjustments areincorrectReplace
Engine idles irregularly or stallsFuel pump is damagedReplace
Engine idles irregularly or stallsAirvent screw onfuel tankis closedLoosen airvent screw
Engine idles irregularly or stallsFuel connection is incorrectConnect correctly
Engine idles irregularly or stallsChoke knob is pulled outReturn to home position
Engine idles irregularly or stallsMotor angle is too highReturn to normal operating position
Engine power lossPropeller is damagedRepair or replace propeller
Engine power lossTrim angle is incorrectAdjust trim angle to achieve most efficient operation
Engine power lossMotoris mounted at incorrect transom heightAdjust motor to proper transom height
Engine power lossBoat bottom isfouledwithmarine growthClean boat bottom
Engine power lossWeeds or other foreign matter are tangled on gear housingRemoveforeignmatter and clean lower unit
Engine power lossSpark plug(s) are fouled or incorrect typeInspect spark plug(s).Clean or replace with recommended type
Engine power lossFuel systemis obstructedCheckfor pinched or kinked fuel line or other obstructions infuel system
Engine power lossFuel filter is cloggedReplace with recommended type
Engine power lossFuel is contaminated or staleFill tank with clean,fresh fuel
Engine power lossSpark plug gap is incorrectInspect and adjust as specified
Engine power lossIgnition wiring is damaged or poorly connectedCheck wires for wear or breaks.Tighten all loose connections.Replace worn orbroken wires
Engine power lossIgnition parts have failedReplace
Engine power lossSpecified engine oil is not being used or oilis added too muchCheck andreplace oilas specified,or add engine oil to specified position
Engine power lossThermostat is faultyReplace
Engine power lossFuel pump hasmalfunctionedReplace
Engine power lossFuel joint connection is incorrectConnect correctly
Engine power lossSpecified spark plug(s) are not being usedCheck and replace spark plug(s) as specified
Engine vibrates excessivelyPropeller is damagedRepair or replace propeller
Engine vibrates excessivelyPropeller shaft is damagedReplace
Engine vibrates excessivelyWeeds or other foreignmatter are tangled on propellerRemove and clean propeller
Engine vibrates excessivelyMotormountingboltislooseTighten bolt
Engine vibrates excessivelySteering islooseTighten steering pivot
Engine vibrates excessivelySteering pivot is damagedReplace