1974 Ski-Doo Shop Manual, Page 127Get this manual
then slowly turn magneto back counter-clockwise until timing light fluctuates or tone signal is no longer heardAt this point, check the distance between pole shoe trailing edge and magnet (edge gap) with strip of cardboard of appropriate width (Refer to Technical Data Section) Edge ga p
If the edge is less than specified, loosen armature te retaining screws and rotate armature plate ass'y counter -clockwise until correct edge gap is obtainedReset the ignitiol9 timing and recheck the edge gap If the edge gap is greater than specified, loosen armature plate retaining screws and rotate armature plate ass'y clockwise until correct edge gap is obtainedReset the ignition timing and recheck the edge gap9Rotate cranksh'aft approx 180 or until PTO piston approaches top dead centerDisconnect timing instru ment wire from blue wire then reconnect it to the black wire leading from engineRepeat steps and for PTO side breaker points10Disconnect timing instrument and reinstall previously removed components on engine
5Disconnect junction block at engine, then connect one lead of timing light (flashlight type or ton timer), to the blue wire (magside) leading from engine Connect other wire to fan cowl (ground)6Install and adjust T.D.Cgauge engine as follows Rotate crankshaft until mag side piston is just before top dead center With gauge in adaptor, adjust roller so that it is parallel with dial face- Tighten roller lock nut