1983 Ski-Doo Shop Manual, Page 200Get this manual
SECTION 04 ELECTRICAL SUB-SECTION 02 (IGNITION TIMING)
5Install and adjust T.D.Cgauge on engine as follows: Rotate magneto clockwise until piston is just before top dead center
With gauge if) adaptor, adjust roller so that it is parallel with dial faceTighten roller lock nut
position
advance position
Adaptor lock nut
NOTE: Ignition timing can change upon tightening Always recheck after tightening
Edge gap verification
By following either of the two procedures herein mentioned the edge gap will automatically be adjustedHowever, if the edge gap is to be verified, proceed as follows: From timing marks, rotate magneto clockwise 14 of turn, (for 247 engine type hold advance mechanism centrifugal weight in full advance position (toward magneto rim)), then slowly turn magneto back counter-clockwise until timing light fluctuatesAt this point check the distance between generator coil end and magnet (edge gap), with cardboard strip of appropriate width