Engine oil level too low, high oil consumption

• Oil consumption

• External oil leaks

• Worn valve guide or stem seal

• Worn piston rings

• Improperly installed piston rings

• Worn cylinder

 

Engine oil contamination

• Oil not changed often enough

• Worn valve guide or stem seal

• Worn piston rings

• Improperly installed piston rings

• Worn cylinder

 

Oil emulsification

• Faulty cylinder head gasket

• Leaky coolant passage

• Entry of water

• Faulty water pump mechanical seal

 

8-2

LUBRICATION SYSTEM

LUBRICATION SYSTEM DIAGRAM

 

ROCKER ARM

 

 

CRANKSHAFT

 

CAMSHAFT

 

OIL FILTER

 

 

OIL PUMP

 

OIL STRAINER SCREEN

 

PRESSURE RELIEF VALVE

 

MAINSHAFT

 

COUNTERSHAFT

 

8-3

LUBRICATION SYSTEM

ENGINE OIL STRAINER SCREEN

 

Be careful not to damage the oil strainer screen.

 

REMOVAL/INSTALLATION

 

Remove the right crankcase cover (page 12-4). Pull the oil strainer screen [1] out of the crankcase.

Wash the oil strainer screen thoroughly in nonflammable or high flash point solvent until all accumulated dirt has been removed.

 

Blow dry it with compressed air to clean completely. Before installing the strainer, it should be examined closely for damage, and make sure the sealing rubber is in good condition.

 

[1]

 

Install the oil strainer screen with the thin edge facing in
OIL STRAINER SCREEN DIRECTION:
and flange side facing up as shown.
Install the right crankcase cover (page 12-8).

 

CRANKCASE

 

OIL PUMP

 

REMOVAL/DISASSEMBLY

 

Remove the right crankcase cover (page 12-4).

Remove the oil pump driven gear [1].

 

[1]

 

Remove the oil pump mounting bolts [1] and oil pump
[1]
assembly bolt [2].

Remove the oil pump cover assembly [3].

 

 

[2]

[3]

 

8-4

LUBRICATION SYSTEM

 

Remove the inner rotor assembly from the oil pump cover [1] while holding oil pump shaft [2].

 

Remove the oil pump shaft and lock pin [3] from the inner rotor [4].

 

Remove the outer rotor [5] and washer [6].

 

Remove the dowel pins [1] from the oil pump body [2].

 

 

Remove the oil pump body [1] by releasing it from the cam chain guide hook [2] and pressure relief valve [3].

 

Remove the dowel pins [4] and O-ring [5].

 

INSPECTION

 

Inspect the following parts for damage, abnormal wear, deformation or burning.

 

– Oil pump driven gear

– Oil pump shaft

– Lock pin

– Inner rotor

– Outer rotor

– Oil pump body

 

Measure the oil pump clearances according to LUBRICATION SYSTEM SPECIFICATIONS (page 1-5).

 

If any of the measurement is out of the service limit, replace the oil pump as an assembly.

 

[5]

[2]

[4]

 

[1]

[6]

[3]

 

[2]				[1]
	[1]			[2]

 

 

[4]

 

		[3]
[5]

 

8-5

LUBRICATION SYSTEM

ASSEMBLY

 

		O-RING
OIL PUMP BODY

 

		DOWEL PINS
OIL PUMP COVER

 

OIL PUMP DRIVEN GEAR
INNER ROTOR

 

LOCK PIN

 

OIL PUMP SHAFT

 

OUTER ROTOR

 

WASHER

 

OIL PUMP ASSEMBLY BOLT

 

OIL PUMP MOUNTING BOLTS

 

INSTALLATION

 

Install the dowel pins [1].

 

Apply engine oil to a new O-ring [2].

Install the O-ring to the oil pump assembly [3].

 

Install the oil pump assembly while aligning its slit with cam chain guide hook and its hole with the pressure relief valve.

 

 

Install and tighten the oil pump mounting bolts [1].

 

If the oil pump was disassembled, tighten the oil pump assembly bolt [2].

 

[3]

[1]

 

 

		[2]		Align		Align

[1]

 

 

[2]

 

8-6

LUBRICATION SYSTEM

 

Apply engine oil to the oil pump driven gear [1] teeth.

 

Install the oil pump driven gear while aligning the flats of the oil pump driven gear and oil pump shaft.

 

Install the right crankcase cover (page 12-8).

 

 

PRESSURE RELIEF VALVE

 

REMOVAL/INSTALLATION

 

Remove the oil pump (page 8-4).

 

Remove the oil pressure relief valve [1] and O-rings [2].

 

Apply engine oil to new O-rings.

Install the O-rings to the oil pressure relief valve grooves.

 

Install the oil pressure relief valve into the right crankcase with the piston side facing outside.

 

Install the oil pump (page 8-6).

 

PRESSURE RELIEF VALVE INSPECTION

 

Check the operation of the pressure relief valve by pushing on the piston [1].

 

Disassemble the pressure relief valve by removing the snap ring [2].

 

 

Remove the washer [1], spring [2] and piston [3].

 

Check the piston for wear, sticking or damage. Check the spring for fatigue or damage.

 

Assemble the pressure relief valve in the reverse order of disassembly.

• Install the snap ring with the chamfered edges facing the thrust load side.

 

• Make sure the snap ring is seated in the groove.

Align

 

 

[1]

 

[2]

 

[1]

 

[1]

[2]

 

 

[3]

[2]

[1]

 

 

8-7

MEMO

COOLING SYSTEM

 

SERVICE INFORMATION·····························9-2

 

TROUBLESHOOTING···································9-2

 

SYSTEM FLOW PATTERN···························9-3

 

SYSTEM TESTING········································9-4 COOLANT REPLACEMENT·························9-5 THERMOSTAT ··············································9-5

 

RADIATOR/COOLING FAN··························9-6

 

WATER PUMP ··············································9-8

 

RADIATOR RESERVE TANK·····················9-12

 

FAN CONTROL RELAY ·····························9-12

 

WATER PIPE ··············································9-13

 

 

9-1

COOLING SYSTEM

SERVICE INFORMATION

 

GENERAL

 

Removing the radiator cap while the engine is hot can allow the coolant to spray out, seriously scalding you. Always let the engine and radiator cool down before removing the radiator cap.

 

Using coolant with silicate inhibitors may cause premature wear of water pump seals or blockage of radiator passages. Using tap water may cause engine damage.

 

• Add cooling system at the reserve tank. Do not remove the radiator cap except to refill or drain the system.

• All cooling system services can be done with the engine installed in the frame.

• Avoid spilling coolant on painted surfaces.

• After servicing the system, check for leaks with a cooling system tester.

 

TROUBLESHOOTING

 

Engine temperature too high

• Faulty indicator or ECT sensor

• Thermostat stuck closed

• Faulty radiator cap

• Insufficient coolant

• Passage blocked in radiator, hoses or water jacket

• Air in system

• Faulty cooling fan motor

• Faulty fan control relay

• Faulty water pump

 

Engine temperature too low

• Thermostat stuck open

• Faulty fan control relay

 

Coolant leak

• Faulty water pump mechanical seal

• Deteriorated O-ring

• Faulty radiator cap

• Damaged or deteriorated cylinder head gasket

• Loose hose connection or clamp

• Damaged or deteriorated hoses

• Damaged radiator

 

 

9-2

COOLING SYSTEM

SYSTEM FLOW PATTERN

 

 

RADIATOR

 

WATER HOSE

 

SIPHON HOSE

 

RESERVE TANK

 

 

THERMOSTAT

 

 

WATER HOSE

 

 

WATER PIPE

 

WATER PUMP

 

 

9-3

COOLING SYSTEM

 

SYSTEM TESTING