1982 Ski-Doo Shop Manual, Page 12Get this manual
SECTION 01 TOOLS SUB-SECTION 02 (SERVICE TOOLS)
Polyamid ring pusher engine 277 MAG 420 273 930 PTa 420 273 940
To install polyamid ring in crankcase
277 engine
Crankshaft feeler gauge503 engine MAG 420876625 PTa 420 876 620
Mag side: All 503 engine up to no3 181 891 and engines no3 181 921 to 181 937 PTa: all 503 engines