1978 Ski-Doo Shop Manual, Page 227Get this manual
SECTION 04 SUB-SECTION 04, (IGNITION TIMING)
CD IGNITION345354 IENGINE TYPES
FOREWORD
On models equipped with C.Dignition system, plug firing is initiated by an electrical pulseThis pulse is released when metal projection on the flywheel hub rotates near the pick-up coilTherefore, timing must be performed while the engine is runningCAUTION: Running the engine unnecessarily will cause premature slider shoe wearIf the timing marks do not coincide, .remove rewind starter and starting pulleySlacken off the two (2) Allen capscrews securing the armature plateRotate plate clockwise if timing is advanced, counter-clockwise if timing is retardedTirnlnq marks
A stroboscopic timing light such as Sun PTL 45, Snap-: On MT215B, Bosch EFAW 169A, or suitable equivalent, plus 12 volt battery are needed
345 ENGINE TYPE
Place ski tips against wallUse support incorporating protective guard to block vehicle off the ground(Approx15 cm (6"r between track and floor)Remove rubber plug from upper crankcase halfConnect an operating timing light to magneto side spark plug wire