Polaris SPORTSMAN 600 2003 Service Manual page 109

ENGINE ENGINE
TROUBLESHOOTING, CONT
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 Wet sumping
G Worn rings, piston, or cylinder
G Worn valve guides or seals
G
Restricted breather
G Air filter dirty or contaminated
Low Compression
G Cylinder head gasket leak
G No valve clearance ( cam wear )
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 sealing
surface)
G Rocker arm sticking
Backfiring
G
ETC or speed limiter system
malfunction
G
Fouled spark plug or incorrect plug
or plug gap
G Carburetion faulty - lean condition
G Exhaust system air leaks
G
Ignition system faulty:
Spark plug cap cracked/broken
Ignition coil faulty
Ignition or kill switch circuit faulty
Ignition timing incorrect
Sheared flywheel key
G Poor connections in ignition system
G Valve sticking
G Air leaks in intake
G Lean condition
COOLING SYSTEM
TROUBLESHOOTING
Overheating
G Low coolant level
G
Air in cooling system
G Wrong type/mix of coolant
G Faulty pressure cap or system
leaks
G Restricted system (mud or debris in
radiator fins causing restriction to
air flow, passages blocked in
radiator, lines, pump, or water
jacket, accident damage)
G
Lean mixture (restricted jets, vents,
fuel pump or fuel valve)
G Fuel pump output weak
G
Electrical malfunction
G
Water pump failure/ Loose impeller
G
Thermistor failure
G
Cooling fan inoperative or turning
too slowly (perform current draw
test)
G Ignition timing misadjusted
G Low oil level
G
Spark plug incorrect heat range
G
Faulty hot light circuit
G
Thermostat stuck closed or not
opening completely
Temperature Too Low
G
Thermostat stuck open
Leak at Water Pump Weep Hole
G Faulty water pump mechanical seal
(coolant leak)
G Faulty pump shaft oil seal (oil leak)
3.57