How to Replace the Thermostat in a 1997 Chevy Monte Carlo
- 1). Park the car on a level surface and allow the engine to cool before performing this repair. Once cooled, raise the hood, put on your safety glasses and remove the radiator cap to release the pressure in the hose.
- 2). Disconnect both battery cables for added safety. Place a clean bucket directly under the anti-freeze release drain located on the bottom of the radiator.
- 3). Remove the carburetor air cleaner and filter unit. Unscrew the center cap using your hand.
- 4). Slide underneath the car on your back and loosen the drain bolt using a socket wrench. Drain out a portion of anti-freeze to clear out the upper radiator hose that attaches to the thermostat housing cover, then re-tighten the bolt.
- 5). Disconnect the upper radiator hose where it attaches to the thermostat cover and tube. It is secured in place with a spring hose clamp. Squeeze the clamp using channel-lock pliers and slide it off the cover. Keep the opposite end that connects to the radiator attached during this repair.
- 6). Take out the two mounting bolts that secure the thermostat housing cover to the block using a socket wrench. Gently tap the cover using a rubber mallet to break the seal and remove the old thermostat. Scrape away the old gasket using a gasket scraper or razor, being careful not to allow any debris to enter the engine.
- 1). Pre-test the new thermostat before installing to confirm that it's functioning properly. Fill a 3- or 4-inch deep bowl with very hot water. Grasp the thermostat upright using channel-lock pliers, and hold it in the hot water; be sure to cover the entire unit. The lower spring side of the thermostat should open immediately, indicating that it is functioning properly.
- 2). Apply a small dab of gasket sealer to the replacement gasket using your finger. Place the gasket directly onto the block at the thermostat housing opening. Make certain that the mounting holes are correctly aligned so that the thermostat and cover will seat properly.
- 3). Insert the new thermostat upright with the spring side inserted into the engine. Carefully replace the housing cover. Be careful not to move the gasket or disturb the alignment and secure it on with the two mounting bolts.
- 4). Replace the carburetor air cleaner and filter unit, then reconnect the upper radiator hose to the thermostat cover and secure it in place with the spring hose clamp. Inspect the hose for damage or bulging and replace it if necessary.
- 5). Reconnect both battery cables and start the engine. While the engine is idling, pour the drained anti-freeze back into the radiator. Let the engine continue to idle for several minutes to allow any trapped air to escape. Inspect the thermostat and hose connection for leaks. Add additional anti-freeze if necessary, then replace the radiator fill cap.