Polaris 2009 Trail Boss 330 Service Manual page 93

TROUBLESHOOTING
Piston Failure - Scoring
G Lack of lubrication
G
Dirt entering engine through cracks
in air filter or ducts
G
Engine oil dirty or contaminated
Excessive Smoke and Carbon Buildup
G Excessive piston-to-cylinder
clearance
G
Worn rings, piston, or cylinder
G Worn valves, guides or seals
G Restricted breather
G
Air filter dirty or contaminated
Low Compression
G
Decompressor stuck
G
Cylinder head gasket leak
G
No valve clearance or incorrectly
adjusted
G Cylinder or piston worn
G Piston rings worn, leaking, broken, or
sticking
G Bent valve or stuck valve
G Valve spring broken or weak
G Valve not seating properly (bent or
carbon accumulated on valve area)
G
Rocker arm sticking
Backfiring
G ETC or speed
malfunction
G
Fouled spark plug or incorrect plug or
plug gap
G Carburetion faulty - lean condition
G Intake / Exhaust system air leaks
G Ignition system faulty:
GSpark plug cap cracked/broken
GIgnition coil faulty
GIgnition or kill switch circuit
faulty
GIgnition timing incorrect
GSheared flywheel key
G
Poor connections in ignition system
G System wiring wet
G Cam lobe worn or Valve sticking
G Lean condition
limiter system
ENGINE
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