2001 Polaris Sportsman 400-500 DUSE and H.O. Service Manual, Page 147Get this manual
TROUBLESHOOTING
Engine Turns Over But Fails to Start
&&&&& No fuel Dirt in fuel line or filter Fuel will not pass through fuel valve Fuel pump inoperativerestricted Tank vent plugged Carb starter circuit Engine flooded Low compression (high cylinder leakage) No spark (Spark plug fouled)
Engine Does Not Turn Over
&& Dead battery Starter motor does not turn Engine seized, rusted, or mechanical failure
Engine Runs But Will Not Idle
&&&&&&&& Restricted carburetor pilot system Carburetor misadjusted Choke not adjusted properly Low compression Crankcase breather restricted Spark plug fouledweak spark Broken throttle cable Obstruction in air intake Air box removed (reinstall all intake components) Incorrect or restricted carburetor jetting ETC switch limiting speed Reverse speed limiter limiting speed Carburetor vacuum slide stickingdiaphragm damaged Incorrect ignition timing Restricted exhaust system