1969 Ski-Doo Snowmobiles Service Manual, Page 102Get this manual
IGNITION TIMING (300,320,370 ENGINES) BREAKER POINT Remove engineRemove fan cowl cover Unscrew nut and washer and remove flywheel Check breaker point conditionInstall new set if necessary
ADJUSTMENTUse gauge (Breaker point gap .014 to .018)Connect the tester (Timing flashlight or Merc-O-Tronic)Attach one wire to black wire in connector, ground the other Reinstall flywheel and turn until marks on labyrinth ring and on flywheel coincideAt this point, the breaker should open and the light on the tester should go out