REMOVAL & INSTALLATION
See Figures 1 through 10
The thermostat on the 3.0L engines (except Premier and Monaco) is located in a water box, formed in the timing belt end of the intake manifold. This thermostat has an air bleed valve, located in the thermostat flange. 3.3L and 3.8L engines have the thermostat housing in a water box, formed in the drive belt side of the intake manifold. The thermostat of the Premier and Monaco 3.0L engine is located on the front of the engine, either in an upright position or mounted in a vertical orientation.
When servicing the thermostat, do not allow coolant to drip onto the accessory drive belt or accessory drive pulleys. If coolant does contact the drive belt or pulleys, flush them with clean water.
- Drain the cooling system to a level below the thermostat.
- Disconnect the coolant temperature sensor wire from the sensor, if necessary.
- Remove the spark plug wire holder from the top of the thermostat housing on Premiers and Monacos. Place shop towels on belts and pulleys.
- Remove the hose clamp and then disconnect the hose from the thermostat housing.
- Remove the two mounting bolts and then remove the thermostat housing.
- Remove the thermostat and discard the gasket. Clean both gasket surfaces thoroughly.
- Dip the new gasket in water and then install it. Position the thermostat in the water box, making sure it is properly seated by centering it in the water box, on top of the gasket. Install the housing and install the two bolts. Tighten thermostat housing retaining bolts gradually and evenly to 9 ft. lbs. (12 Nm).
On the Premier and Monaco-position the air bleed valve toward the back of the thermostat well, this is the highest point of the well which is where the air will settle.
- Reconnect the hose, then position and tighten the hose clamp.
- Close the radiator drain plug, if still open.
- Refill the cooling system, start the engine, and check for leaks. After the engine has reached operating temperature, allow it to cool. Then, recheck coolant level in the radiator, refilling as necessary.