1980 Ski-Doo Shop Manual, Page 219Get this manual
SECTION 05 SUB-SECTION 01 (PULLEY GUARD)
REMOVAL
Pullout hair pin and remove driven pulley guardPull
on spring to disengage pin from frame bracketin order
to disengage drive pulley guard
8The length of uncompressed pin spring should not be less than 47 mm (1 k")An uncompressed front guard spring should not be less than 20 mm (1316")When assembling adjust length to 17 mm (1116")+
WARNING: Never start engine until pulley guard is well installed