2003 Polaris Deep Snow Snowmobiles Service Manual, Page 125Get this manual
ENGINES Engine Troubleshooting
PROBLEM Will not start hard starting PROBABLE CAUSE -Check ignition switch for run position, moisture contamination -Check auxiliary shut-off switch operation -Check fuel supply -Check wiring from engine to coil(s) or spark plug(s) -Check spark plug(s) -Disconnect engine connector to eliminate any shorts that might be in the system -If starter won't work (electric models), check wires from starter solenoid and battery or check battery and battery cables -Open or broken reed valves -Crankcase plug is out -Head gasket faulty -Poor ring sealing, piston damage -Spark plug fouled -Secondary coil faulty or wires disconnected; poor ground on secondary coil mount -Primary coil shorted or open -Ignition switch shorted, contaminated with moisture -Auxiliary switch shorted or contaminated with moisture
Low compression No spark
Engine idles but -Restricted fuel flowair flow no acceleration -Clogged main jet -Timing -Clutching -Engine not running on all cylinders Engine runs but fails to reach maximum RPM -Clogged fuel filter -Incorrect track tension -Incorrect main jet -Throttle slides not fully open -Chain too tight -Clutching -Excessive driveline friction (HiFax overheating) -Engine not running on all cylinders -Incorrect air mixture setting -Throttle stop screw incorrectly adjusted -Restricted pilot jet -Low compression -Tight belt -Piston damage -Enricher plunger not seating properly -Enricher plunger are not seating properly -Fuel pump diaphragm is ruptured (caused by engine backfiring) -Carburetor slides are not synchronized -Main jet too large -Needle and seat not seating properly -Incorrect float level -Check reed valve condition