Thermostat: Service and Repair

Thermostat Replacement

Removal Procedure





1. Remove the air cleaner and duct assembly.
2. Drain the coolant until the coolant level is below the thermostat.
3. Remove the crossover exhaust pipe.
4. Remove the radiator hose from the thermostat housing.
5. Remove the thermostat housing bolts and clean any sealer from the bolt threads.
6. Remove the thermostat housing and gasket.





7. Remove the thermostat.
8. Clean the mating surfaces.

Installation Procedure





1. Install the thermostat.





2. Install the thermostat housing and gasket.
3. Install RTV sealer, GM P/N 12378521 or the equivalent, to the thermostat housing bolt threads.





Notice: Refer to Fastener Notice in Service Precautions.

4. Install the thermostat housing bolts.
^ Tighten the bolts to 25 Nm (18 ft. lbs.).
5. Install the radiator hose to the thermostat housing.
6. Install the crossover exhaust pipe.
7. Install the air cleaner and duct assembly.
8. Fill the cooling system.
9. Inspect the cooling system for leaks. Repair as necessary.