10. TROUBLESHOOTING
10-8
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Snow/water intrusion through intake system into combustion chamber. Clean intake
system and replace defective part(s).
4.
Melted and/or perforated piston dome; melted section at ring end gap.
◼
Spark plugs heat range is too hot. Install recommended spark plugs (refer to
TECHNICAL SPECIFICATIONS).
◼
Coolant less than recommended level (engine gets too hot). Repair cooling circuit and/or
refill with recommended liquid.
◼
Poor quality and/or wrong fuel. Clean from contamination and use appropriate fuel (refer
to TECHNICAL SPECIFICATIONS).
5.
Piston color is dark due to seizure on intake and exhaust side.
◼
Cooling system leaks and lowers coolant level. Tighten clamps or replace defective parts.
Add antifreeze in cooling system until appropriate level s reached. Replace damaged
parts.
6.
Cracked or broken piston.
◼
Cracked or broken piston due to excessive piston/cylinder clearance or engine overheating.
Replace piston. Check piston/cylinder clearance (refer to CYLINDER AND HEAD).
7.
Check piston rings and cylinder surface for grooves.
◼
Poor oil quality. Use recommended oil.
◼
Contamination through engine intake. Replace defective part(s) and use new air filter.
8.
Check crankshaft, rocker arms movement.
◼
Oil pump failure due to lack of oil. Repair and replace defective parts and use new
recommended oil.
◼
Oil contamination due to clogged oil filter/oil strainer. Replace oil and oil filter at the
same time, replace defective part(s).
9.
Check valve springs exhaust/intake.
◼
Broken valve spring damages the cylinder head, valve(s), rocker arm(s), piston, piston
rings and connecting rod. Replace defective part(s).
10.
Check if fuel supply is sufficient.
◼
Low fuel level.
◼
Clogged fuel filter or fuel injector filter.
◼
Fuel line is contaminated and/or bent. Clean and/or replace defective part(s).
Symptom: ENGINE BACKFIRES
1.
Check spark plugs.
◼
Carbon accumulation caused by defective spark plugs. Replace spark plugs.
2.
Check leakage on intake manifold.
◼
Air leak on intake system. Retighten screws and/or replace intake manifold gasket.
3.
Check exhaust air leaking.
◼
Exhaust gasket is leaking. Retighten screws and/or replace exhaust gasket.
4.
Check intake valve(s) for leaking.
◼
Intake valve(s) is (are) leaking. Repair or replace valve(s).
5.
Check if fuel supply is sufficient.
◼
Fuel line is contaminated and/or bent (engine gets lean). Clean and/or replace defective
part(s).
6.
Check engine ground.
◼
Poor engine ground. Clean.
Symptom: ENGINE DOES NOT OFFER MAXIMUM POWER AND/OR DOES NOT REACH MAXIMUM
OPERATING RPM
1.
Check spark plugs condition and/or gap.
◼
Fouled spark plugs or wrong spark plug gap. Readjust gap and clean spark plugs or
replace.
2.
Check spark plugs type.
◼
Improper spark plugs heat range. Install recommended spark plugs (refer to TECHNICAL
SPECIFICATIONS).
3.
Perform engine leak test.
◼
Damaged head gasket and/or seal and/or leaking intake/exhaust valve(s). replace and/or
repair defective parts.
4.
Check for water in fuel (wrong fuel).
◼
There is water in fuel or wrong fuel. Drain fuel system, search for leakage and refill it
with appropriate fuel.
5.
Check engine compression.
◼
Worn piston(s) and/or piston ring(s). Replace defective part(s).
6.
Check fuel pressure.