1997 Ski-Doo Factory Shop Manual Volume Three, Page 86Get this manual
Section 03 ENGINE Sub-Section 06 (LIQUID COOLING SYSTEM)
INSPECTION
Check general condition of hoses and clamp tightness
5, Thermostat
To check thermostat, put in water and heat waterThermostat should open when water temperature reaches the following degreeENGINE All TEMPERATURE 42C (108F)
DRAINING THE SYSTEM
WARNING
Never drain or refill the cooling system when engine is hotTo drain the cooling system, siphon the coolant mixture from the coolant tankUse primer pump with plastic hose inserted as deep as possible into the lower hose
The thermostat is double action typeaIts function is to give faster warm up of the engine by controlling circuit; water pump engine coolant tankThis is done by bypassing the radiator circuitA16C02A