Page 210 - Manual Oficina Polaris Sportsman 570 2014 a 2016
P. 210
ENGINE / COOLING SYSTEM
TROUBLESHOOTING Engine Idles But Will Not Accelerate
• Spark plug fouled/weak spark
ENGINE TROUBLESHOOTING • Broken throttle cable
• Obstruction in air intake
Spark Plug Fouling
• Air box removed (reinstall all intake components)
• Spark plug cap loose or faulty • Incorrect ignition timing
• Incorrect spark plug heat range or gap • Restricted exhaust system
• PVTsystem calibrated incorrectly/ components worn • Camshaft worn excessively
or mis-adjusted
• Fuel quality poor (old) or octane too high Engine Has Low Power
• Low compression • Spark plug fouled
• Restricted exhaust • Cylinder, piston, ring, or valve wear or damage (check
• Weak ignition (loose coil ground, faulty coil, or stator) compression)
• Restricted air filter (main or pre-cleaner) or breather • PVT not operating properly
system • Restricted exhaust muffler
• Improperly assembled air intake system • Camshaft worn excessively
• Restricted engine breather system
• Oil contaminated with fuel Piston Failure - Scoring
• Lack of lubrication
Engine Turns Over But Fails To Start
• Dirt entering engine through cracks in air filter or ducts
• No fuel • Engine oil dirty or contaminated
• Dirt in fuel line or filter
• Fuel will not pass through fuel valve Excessive Smoke and Carbon Buildup
• Fuel pump inoperative/restricted • Excessive piston-to-cylinder clearance
• Tank vent plugged or pinched • Wet sumping due to over-full crankcase
• Engine flooded • Worn rings, piston, or cylinder
• Low compression (high cylinder leakage) • Worn valve guides or seals
• No spark (Spark plug fouled) ignition component • Restricted breather
failure
• Air filter dirty or contaminated
Engine Does Not Turn Over
Low Compression / Excessive Cylinder Leakage
• Brake pedal not engaged • Cylinder head gasket leak
• Dead battery • No valve clearance (cam wear)
• Starter motor does not turn • Cylinder or piston worn
• Engine seized, rusted, or mechanical failure
• Piston rings worn, leaking, broken, or sticking
• Bent valve or stuck valve
Engine Runs But Will Not Idle
• Valve spring broken or weak
• Restricted fuel supply • Valve not seating properly (bent or carbon
• Low compression accumulated on sealing surface)
• Crankcase breather restricted • Rocker arm sticking
Backfiring
• Fouled spark plug or incorrect plug or plug gap
• Intake system air leaks
• Exhaust system air leaks
• Valve sticking
• Ignition system faulty:
• Spark plug cap cracked / broken
• Ignition coil faulty
• Ignition or kill switch circuit faulty
• Poor connections in ignition system
• Ignition timing incorrect
• Sheared flywheel key
3.88 9926803 R06 - 2014-2016 Sportsman 325 / ETX / 450 HO / 570 Service Manual
© Copyright Polaris Industries Inc.
