1997 Ski-Doo Factory Shop Manual Volume One, Page 184Get this manual
Section 05 ELECTRICAL Sub-Section 03 (IGNITION TIMING)
IGNITION TIMING
NIPPONDENSO CDI SYSTEM (WITHOUT TRIGGER COIL)
277 Engine Type The 277 engine type uses single coil ignition systemRefer to CDI SYSTEM 03-05 for more informationsThis section is mainly divided in parts, the first one using Top Dead Center gauge to verify the magneto flywheel timing mark positionThe second one using stroboscopic timing light to check ignition timingFlywheel timing mark position verification is required to: 1Troubleshoot missing or broken magneto flywheel Woodruff key2Troubleshoot magneto flywheel corresponding to different engine type3Scribe the timing mark on new service magneto flywheelAlways verify magneto flywheel timing mark position before checking ignition timing.90 80