1980 Ski-Doo Shop Manual, Page 84Get this manual
SECTION 03 SUB-SECTION 02, (ENGINES)
CLEANING
Discard all gasketsClean all metal components in non-ferrous metal cleaner
Cross torque cylinder head nuts to 20 Nom (15 It-Ibs); torque each cylinder head individually00position nuts and distance nuts as illustrated
Scrape off carbon formation from cylinder exhaust port, cylinder head and piston dome using wooden spatula
NOTE: The letters "AUS" (over an arrow on the piston dome) must be visible after cleaning
Clean the piston ring grooves with groove cleaner toolor with piece of broken ring