2010 Polaris Sportsman 850 Service Manual, Page 157Get this manual

2010 Polaris Sportsman 850 Service Manual, Page 157

ENGINE Engine Turns Over But Fails To Start No fuel Dirt in fuel line, filter, or injectors Fuel pump inoperativerestricted
or damage (check compression) PVT not operating properly Restricted exhaust muffler Camshaft worn excessively Piston FailureScoring
Lack of lubrication Dirt entering engine through cracks in air filter or ducts Engine oil dirty or contaminated (water) Excessive
Smoke and Carbon Buildup Excessive piston-to-cylinder clearance Worn rings, piston, or cylinder Worn valve guides or seals
Restricted breather Air filter dirty or contaminated Low Compression No valve clearance Valve not seating properly (bent
valve or carbondebris accumulated on sealing surface) Cylinder head gasket leak Cylinder or piston worn Piston rings worn,
leaking, broken, or sticking Bent valve or stuck valve Valve spring broken or weak Rocker arm sticking Backfiring Fouled
spark plug or incorrect plug or plug gap Speed limiter system malfunction Exhaust system air leaks Ignition system faulty: