10. TROUBLESHOOTING
10-3
◼
Valve spring damaged (valve always open). Replace spring.
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Valve piston is worn or broken. Replace valve piston (refer to lubrication system).
◼
Valve piston stays open due to contamination. Clean or repair valve piston.
9.
Check plain bearings in crankcase for heavy wear.
◼
plain bearings out of specification (increased clearance). Replace plain bearings (refer to
bottom end).
10.
Check engine oil strainer in crankcase.
◼
Oil strainer is clogged due to contamination. Clean or replace strainer and diagnose
causes. Replace possible damaged parts (refer to bottom end).
Symptom: OIL CONTAMINATION (white appearance)
1.
Check leak indicator hole (in crankcase MAG side-water pump housing area) if water and oil
leaks.
◼
Leakage of oil/water mixture from indicator bore means damaged water pump seal ring
and rotary seal. Replace sealing ring, rotary seal and change oil, oil filter and/or coolant
(refer to lubrication system, cooling system and bottom end).
2.
Check cylinder head and/or cylinder base gasket..
◼
Gasket damaged or leaking. Retighten cylinder head with recommended torque and/or
replace gasket.
3.
Check tightening torque of cylinder head screws.
◼
Screws not properly tightened. Retighten screws to recommended torque and replace oil.
4.
Check oil for particles (may indicate possible engine internal damages).
◼
Oil contamination due to metal or plastic particles. Replace possibly damaged part(s)
including oil and oil filter. Use recommended oil (refer to technical specifications).
CYLINDER AND HEAD
Symptom: UNUSUAL ENGINE NOISE AND/OR VIBRATION
1.
Check noise coming from cylinder head area.
◼
Improper valve clearance adjustment. Readjust valve clearance and/or replace defective
part(s).
◼
Faulty chain tensioner. Replace spring and/or mechanism.
◼
Chain guide worn out. Replace chain guide.
◼
Stretched chain and/or worn out sprockets. Replace chain and sprockets.
◼
Sprocket screws got loose. Retighten screws with recommended torque.
◼
Rocker arm(s) is (are) worn out (valve adjustment). Readjust valve clearance and/or
replace rocker arm(s).
◼
Incorrect camshaft timing adjustment. Replace damaged components and readjust
camshaft timing (refer to cylinder and head).
Symptom: OIL CONTANMINATION ON CYLINDER AND/OR HEAD
1.
Check screws for torque.
◼
Loose screws. Retighten screws with recommended torque.
◼
Gaskets are brittle, hard, worn out or otherwise damaged. Replace damaged gaskets,
O-rings or the V-ring on breather.
CRANKSHAFT
Symptom: UNUSUAL ENGINE NOISE AND/OR VIBRATION
1. Check noise coming from crankshaft area..
◼
Crankshaft plain bearings are damaged,. Replace crankshaft plain bearings.
◼
Connecting rod plain bearings are damaged. Replace connecting rod plain bearings.
◼
Magneto rotor got loose. Replace damaged components and retighten rotor retaining
screw with recommended torque (refer to MAGNETO SYSTEM).
GEARBOX
Symptom: UNUSUAL GEARBOX NOISE AND/OR VIBRATION
1.
Check oil level in gearbox.
◼
Oil leakage from gearbox. Replace damaged gasket(s) and/or oil seal(s), torque screws
and refill with oil up to specified level (refer to TECHNICAL SPECIFICATIONS and
GEARBOX)
2.
Check bearings in the gearbox for free movement.
◼
Bearing(s) do(es) not move freely. Replace bearing(s)
3.
Check for knocking noise.
