Polaris SPORTSMAN 600 Service Manual page 107

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