1984 Ski-Doo Shop Manual, Page 190Get this manual
SECTION 03 TRANSMISSION
SUB-SECTION 02 (DRIVE BELT)
TROUBLE SHOOTING
1Uneven belt wear on one side only
a) Tighten engine mount nuts equallyb) Align pulleysc) Repair or replace pulley half
a) Loosen engine mountb) Pulley misalignmentc) Rough or scratched pulley surfaces2Belt glazed excessively or having baked appearance