1980 Ski-Doo Shop Manual, Page 54Get this manual
SECTION 03 SUB-SECTION 02 (ENGINES)
0To remove or install seal inside the crankcase,
use no 420 277 865 pusher for magneto side and no420876 660 pusher for P.T.Oside
NaTE: To remove sealspush from outside the crankcase towards the insideTo install push from the inside towards the outside