Engine Coolant Thermostat Replacement 3.1L

Tools Required

J 38185 Hose Clamp Pliers

1. Remove the air cleaner and duct assembly. Refer to Air Cleaner Assembly Replacement in Engine Controls - 3.1L.
2. Partially drain the coolant. Refer to Cooling System Draining and Filling .
3. Use the J 38185 in order reposition the hose clamp at the thermostat housing.
4. Disconnect the radiator hose from the thermostat housing.



5. Remove the thermostat housing attaching bolts.



6. Remove the thermostat housing and gasket.



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

1. Install the thermostat.



2. Install the thermostat housing and gasket to intake manifold.




Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

3. Install the bolts to the housing with RTV sealer GM P/N 1052366 or the equivalent.

Tighten
Bolts to 25 N·m (18 lb ft).

4. Connect the radiator hose to the thermostat housing.
5. Use the J 38185 in order reposition and install the hose clamp at the thermostat housing.
6. Install the air cleaner and duct assembly. Refer to Air Cleaner Assembly Replacement in Engine Controls - 3.1L.
7. Fill the cooling system. Refer to Cooling System Draining and Filling .
8. Inspect for leaks.

Engine Coolant Thermostat Replacement 3.8L

Tools Required

J 38185 Hose Clamp Pliers

1. Remove the fuel injector sight shield. Refer to Fuel Injector Sight Shield Replacement in Engine Mechanical - 3.8L.
2. Partially drain the engine coolant from the coolant system. Refer to Cooling System Draining and Filling .
3. Carefully disconnect the throttle body air inlet duct. Refer to Air Cleaner Assembly Replacement in Engine Controls - 3.8L.
4. Use the J 38185 in order to reposition the hose clamp at the water outlet housing. Disconnect the radiator hose from the water outlet housing.



5. Remove from the water outlet housing bolts.
6. Remove the water outlet housing and gasket.
7. Remove the thermostat.
8. Inspect and clean the mating surfaces.

•	Water outlet housing

•	Lower intake manifold

1. Install the thermostat.
2. Install the gasket and the water outlet housing.

Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

3. Install the water outlet housing bolts with RTV Sealer GM P/N 1052366 or equivalent.

Tighten
Tighten the bolts to 27 N·m (20 lb ft).




4. Connect the radiator hose to the water outlet housing. Use the J 38185 in order to reposition and install the hose clamp at the water outlet housing.
5. Carefully install the throttle body air inlet duct. Refer to Air Cleaner Assembly Replacement in Engine Controls - 3.8L.
6. Fill the cooling system. Refer to Cooling System Draining and Filling .
7. Install the fuel injector sight shield. Refer to Fuel Injector Sight Shield Replacement in Engine Mechanical - 3.8L.
8. Inspect for leaks.