Thermostat: Service and Repair

REMOVAL
Do not remove pressure cap while engine is hot or under pressure. Ensure coolant does not drip onto accessory drive belt or drive pulley. If it does, flush with clean water.
1. Drain coolant into a clean container for reuse. Drain until level is below the thermostat housing.
2. Disconnect coolant temperature sensor wire connector from sensor on housing.
3. Remove upper radiator hose and intake manifold hoses.
4. Remove retaining bolt, housing, gasket and thermostat.
5. Clean mating surfaces of housing and intake manifold. Ensure that draincock is closed.

INSTALLATION

1. Install thermostat into recess in cylinder head, ensuring that "TO RAD", stamped on thermostat, is pointing in right direction and air bleed valve pointing up.
2. Install new gasket and thermostat housing. Ensure that thermostat is seated properly in recess.
3. Install two retaining bolts, then tighten to specifications.
4. Install upper radiator hose, intake hoses and ensure draincock is closed.
5. Connect temperature sensor connector and fill cooling system with proper 50/50 mixture of antifreeze, then replace pressure cap.
6. Start engine and run until warm. Check for leaks, then recheck coolant level. Fill as necessary, the radiator and reserve.