How to Replace the Thermostat on a '95 Pontiac Grand Prix

The thermostat installed in the engine of a 1995 Pontiac Grand Prix acts like a thermostat in your house. When it reaches a certain temperature, it opens up to allow coolant to circulate throughout the system. When the thermostat stops working, then coolant no longer flows between the radiator and the engine, which can create a high-temperature condition. This can overheat the engine and potentially damage the engine beyond repair. Replacing the thermostat is inexpensive and simple to do, and will take less than 30 minutes to do.

Instructions

1

Allow the car to cool for several hours, until you can put your bare hand on top of the radiator and not get burned.

2

Put the drain pan underneath the radiator and open up the petcock. Drain out about one gallon of coolant out of the system, then close the petcock.

3

Locate the thermostat housing, which is connected to the upper radiator hose on the top of the engine. Unbolt the housing from the engine using the 3/8-inch ratchet and socket, then pull it off the engine with the hose still attached. Notice the orientation of the thermostat, as you will want to set the new thermostat in the same orientation when you install it.

4

Scrape off both mounting surfaces of the thermostat housing with the gasket scraper. Apply a thin coat of RTV sealant to the thermostat housing. Install the replacement thermostat into the housing in the same orientation as the original. Then bolt the housing together using the 3/8-inch ratchet and socket.

5

Open the radiator cap. Fill up the radiator using the 50-50 pre-diluted coolant.