2011 Arctic Cat DVX 300 / 300 Utility ATV Service Manual, Page 82Get this manual
1Attach the Timing Light to the spark plug high tension lead; then remove the timing inspection plug from the left-side crankcase cover2Using the Tachometer, start the engine and run at 1000 RPM; ignition timing should be BTDC ("F" mark) 3Install the timing inspection plugIf ignition timing cannot be verified, the rotor may be damaged, the key may be sheared, the trigger coil bracket may be bent or damaged, or the CDI unit may be faulty
Troubleshooting
Problem: Spark absent or weak Condition
12345Ignition coil defective Spark plug defective Magneto defective CDI unit defective Pick-up coil defective
12345Replace ignition coil Replace plug Replace magneto Replace CDI unit Replace pick-up coil
Problem: Spark plug fouled with carbon Condition
1234567Mixture too rich Idling RPM too high Gasoline incorrect Air cleaner element dirty Spark plug incorrect (too cold) Valve seals crackedmissing Oil rings wornbroken
1234567Adjust carburetor Adjust carburetor Change to correct gasoline Clean element Replace plug Replace seals Replace rings