1980 Ski-Doo Shop Manual, Page 106Get this manual
SECTION 03 SUB-SECTION 02, (ENGINES)
ENGINE SUPPORTMUFFLER
REMOVAL FROM VEHICLE
Disconnect or remove the followings from vehicle: Pulley guard and drive belt Fuel lines, primer, pulsation and oil injection lines Muffler and rewind starter Electric wires WARNING: Always disconnect ground cable first, before any other wire of the starting systemDrain the cooling system and disconnect hoses at engine Rotary valve oil reservoir Disconnect rewind starter at engineAir silencer and throttle cable