· 10 mm socket
· 6" Socket extension
· Gasket scraper (or razor blade)
· Flathead screwdriver
· New Thermostat
· Thermostat rubber “O” ring*
· Thermostat Gasket**
· Extra coolant
· Paper towels and/or shop rags
· Saftey goggles and plastic gloves reccomended

*denotes optional item
**Gasket required for '97/'98 model year Grand Prix's

1.) Before you begin
Be sure you are working with a cold engine, as the coolant system is pressurized and may spray hot coolant at you. We reccomend that you do this on a car which has been sitting over night. Always wear proper saftey equipment (goggles, gloves, etc).

2.) Remove Engine Cover
Open the hood and remove the engine cover. You will need to turn the oil fill snout (not just the cap, the whole snout) counterclockwise and it will unscrew itself. Now the engine cover maybe lifted off of the engine freely.

3.) Remove the t-stat housing
Pull off the plastic wiring bracket from the passenger side bolt. Place rags or paper towels around the housing. Now take the 10mm socket & extension and remove the two 10mm bolts on the thermostat housing. Once you have removed the two 10mm bolts, the t-stat housing is now free and you can move it to the side to access the thermostat. Becareful, about 1/4 cup of coolant pours out during this process.

4.) Remove the t-stat
Either by hand, or with a pair of pliers, gently pull out the thermostat. It may require a little bit of pressure to 'pop' it out of the housing.

<

5.) Put rubber "O"-ring on new t-stat
Either remove the original O ring (if it's in good condition) or replace the O ring and put it on the new t-stat.

6.) Scrape off the old gasket - for '97/'98 models only
Use the gasket scraper or a razor blade to thoroughly clean off all old gasket material. Place a new gasket in place.

7.) Place new t-stat in place
Place the new t-stat with the o-ring on it back into the t-stat housing. Place the radiator hose back on to the t-stat, and reverse the procedures to bolt the t-stat back into place.

8.) Bleed & top off coolant
Now...run the engine for about 15 minutes to warm it up to proper temperature. Take a peice of towel, and a flat head screwdriver and bleed the air out of the system. To do this, on top of the radiator hose at the t-stat, you'll see a little brass valve. Place the towel over it, and then slightly turn the valve counter clockwise with the screwdriver. When only coolant is coming out, you can then close the valve again. Make sure to have the towel there so that the coolant doesn't shoot up at you!! Also, don't forget to top off the coolant.

Click below to go back to www.pfyc.com