Thermostat: Service and Repair

REMOVAL

WARNING: Do not remove the radiator cap while engine is operating or while engine is still under pressure.

1. Drain cooling system until coolant level is below thermostat.
2. Disconnect upper radiator hose at thermostat housing.
3. Remove two housing retaining bolts, then the thermostat housing and gasket.

INSTALLATION
To ensure that the thermostat is correctly installed, the water outlet casting on all engines contains a locking recess into which the thermostat is turned and locked.
1. Clean gasket surface on thermostat housing and intake manifold, then position the thermostat in the housing, with the bridge section in the outlet casting. Turn the thermostat clockwise to lock it in position.
2. Position new gasket and thermostat housing on the manifold, then install two retaining bolts.
3. Connect upper hose to housing, then fill cooling system with recommended coolant.
4. Start engine and check for leaks.