How to Change the Thermostat on a Toyota Tercelby Leonardo R. Grabkowski
The Tercel was Toyota's compact car until 1998 when it was replaced by the Toyota Echo. The Tercel was equipped with a 1.5L engine and had a traditional cooling system. If the thermostat in your Tercel "sticks" or goes out, your engine will not operate in its normal operating range, which can cause severe damage. Thermostat replacement is not recommended for the inexperienced.
Removing the Old Thermostat
Open your hood, and disconnect the negative battery cable before you get started. Loosen the terminal nut with the pliers, and lift the cable from the terminal. If your engine has been running recently, let it cool for at least 30 minutes.
Place a drain pan or another suitable container underneath the front of the engine bay. Look closely underneath the radiator to find the radiator drain plug.
Use the flat head screw driver to remove the plug and let the coolant drain. Cover the coolant and keep it in a safe place.
Unhook the electrical connection attached to the water inlet hose. Remove the two mounting bolts with the pliers or the socket wrench to unhook the housing and access the thermostat.
Remove the thermostat and the gasket. Pay attention to the mounting position of the thermostat. If the new thermostat is installed backwards (It's possible.), you can cause serious problems.
Installing the New Thermostat
Insert the new thermostat into the housing in the exact position as the old one. Make sure the bleed valve is facing up.
Attach the new gasket and the water inlet hose. Tighten the mounting bolts to 43-inch lbs. of torque.
Reinstall the drain plug and refill the cooling system with the coolant you drained unless it is dirty. If it's dirty or contaminated, go ahead and replace it if it's convenient.
Reconnect the negative battery cable, and start the engine. Let the engine idle for about 10 minutes or until it reaches normal operating temperature. (Pay attention to your temperature gauge.)
Check underneath for leaks. Keep a close eye on your temperature gauge for the next few days to make sure everything is working correctly.
- Lifting the front of the vehicle is helpful but not necessary in most situations. If you have trouble accessing underneath the engine bay, feel free to lift and support the front end.
- Keep engine coolant away from children, animals and anyone who may try to consume it. It has a sweet smell, but is deadly. If replacing the coolant, dispose of the old coolant in a proper manner. Check with your local waste authority for engine coolant disposal instructions.