1983 Ski-Doo Shop Manual, Page 85Get this manual
SECTION 02 ENGINE SUB-SECTION 05 (503 ENGINE TYPE)
CLEANING
Discard all gasketsClean all metal components in non-ferrous metal cleanerScrape off carbon formation from cy linder exhaust port, cylinder head and piston dome using wooden spatu la
At assembly, place the pistons ove the connecti ng rods with he letters "AUS" (over an arrow on the piston domel facing in the direction of the exhaust po rt
NOTE: The letters "AUS" (over an arrow on the piston domel must be visible after cleaning
EXHAUST
Clean the piston ring grooves it groove cleaner too l, or with piece of broken ring
DISASSEMBL Y
Place clean cloth over cran kcase to prevent circlips from fa ll ing into crankcaseUse poin ted tool to remove circlips from piston_ CAUTION: When tapping out gudgeon pins, hold piston firmly in place to eliminate the possibilitiesof transmitting shock and pressure to the connecting rodTo min imize he effect of acceleration forces on circli p, insta ll each circlip so the circ lip break is at o'clock as illust ratedRemove any burrs from piston caused through circlip installation using very fine emery cloth