1989 Ski-Doo Repair Manual, Page 373Get this manual
Section 04 ELECTRICAL Sous-section 02 (IGNITION TIMING)
NOTE: Use separate banery to supplV timing light {except on electric starting models; or when using the Electro-Specialty, model TL 2802 timing light} WARNING: Place ski tips against wall, raise rear of vehicle on stand so that track does not contact the groundMake sure no one passes behind the vehicle while engine is running, Keep clear of track and other moving parts
503 engine type; Look through fhe fan and check it the flywheel and the crankcase marks align
2Start the engine and point timing lighr straight in line
with the crankcase timing markBring engine to 6000 APM for brief instantITYPICAl)
M'tlg si:lc
011004001
Timing inspection hole
tf flywheel mark (or reference one previously scribedalign with center mark on crankcase (except on 503 type which has an arrow on crankcase), timing is COtrect