2011 Arctic Cat 450XC Service Manual, Page 71Get this manual
1Inspect the thermostat for corrosion or spring damage2Using the following procedure, inspect the thermostat for proper operation ASuspend the thermostat in container filled with waterBHeat the water and monitor the temperature with thermometerCThe thermostat should start to open at 71-86 (160-187 F)DIf the thermostat does not open, it must be replaced3Inspect all coolant hoses, connections, and clamps for deterioration, cracks, and wearNOTE: All coolant hoses and clamps should be replaced every four years or 4000 milesFI538A
Installing 1Secure the water pump to the engine with the four cap screws tightened to ft-lb
Installing 1Place the thermostat and O-ring into the thermostat housing; then secure the thermostat housing to the mounting bracket with the two cap screws2Fill the cooling system to the recommended level with antifreezeCheck for leakageWATER PUMP
NOTE: The water pump is non-serviceable componentIt must be replaced as an assembly