Engine Troubleshooting - Polaris INDY TRAIL RMK Service Manual

ENGINES

Engine Troubleshooting

PROBLEM
Will not start/ -Check ignition switch for run position, moisture contamination
hard starting -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
Low compres- -Crankcase plug is out
sion -Head gasket faulty
-Poor ring sealing, piston damage
No spark -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
Engine idles but -Restricted fuel flow/air flow
no acceleration -Clogged main jet
-Timing
-Clutching
-Engine not running on all cylinders
Engine runs but -Clogged fuel filter
fails to reach -Incorrect track tension
maximum RPM -Incorrect main jet
-Throttle slides not fully open
-Chain too tight
-Clutching
-Excessive driveline friction (HiFax overheating)
-Engine not running on all cylinders
Engine runs but -Incorrect air mixture setting
fails to idle -Throttle stop screw incorrectly adjusted
-Restricted pilot jet
-Low compression
-Tight belt
-Piston damage
-Enricher plunger not seating properly
Engine runs, -Enricher plunger are not seating properly
but overloads -Fuel pump diaphragm is ruptured (caused by engine backfiring)
with fuel -Carburetor slides are not synchronized
-Main jet too large
-Needle and seat not seating properly
-Incorrect float level
-Check reed valve condition
Carburetion and -Verify all tune up adjustments: carb sync, oil pump adjustment, pilot screw setting, spark plug type
plug fouling and gap, venting for carbs, proper jetting for altitude and temperature, belt tension, clutch operation. If
tune up items are correct, check: float level, jet needle position, jet needle wear, inlet needle and seat
wear, spark quality, etc.
Engine runs but -Coolant level low or air in cooling system
overheats -Incorrect main jet
-Incorrect timing
-Incorrect spark plug
-Water pump belt loose or broken
-Cooling restriction
-Inadequate snow for cooling (ice and/or marginal conditions)
Battery will not -Check for faulty connections
charge (battery -Check alternator output
equipped mod- -Check diodes (rectifier)
els only) -Sulphated battery
-Battery electrolyte overfilled or low
-Refer to alternator testing in chapter 9, electrical
3.72
PROBABLE CAUSE