How to Repair a Broken Radiator Thermostat Sensor

What You'll Need
New radiator thermostat
Ratchet set
Gasket glue
Old rag
Putty knife

In making sure the engine does not overheat, the radiator thermostat is one of the most important parts of a radiator. An engine running hot can lead to serious damage overtime if the thermostat is not doing its job. If the thermostat is not able to register when the engine is running hot it will not be able to properly prompt the radiator to pump coolant throughout the engine to cool it down. To prevent this costly and serious damage from happening, you can replace the radiator thermostat fairly easily all by yourself.

Step 1 – Drain the Coolant

Before you can begin any repair on your car’s radiator, it must be drained of the coolant. Before this is done the car should sit for at least 30 minutes without running to allow all of the engine parts to cool sufficiently. Once the engine has cooled, you can safely drain the coolant out of the radiator and into a container to safely dispose of later. Underneath the car you can usually find the radiator’s drain plug that can be loosened enough to drain with a ratchet. Once you have completely drained the coolant you should only dispose of it in an authorized manner. For exact details you can take it to any mechanic’s shop for assistance or guidance.

Step 2 – Locate the Thermostat

Once the coolant has been drained, you can begin trying to locate the thermostat casing. Once you have found the housing you will need to remove any bolts or screws holding it in place. After you have removed any bolts holding the housing in place you can remove it safely without cracking it. The thermostat opening will need to be wiped with your old rag to clean away any buildup or debris. Once the opening is wiped clean you can replace the thermostat itself.

Step 3 – Replace the Thermostat

Take the old thermostat out and be sure to note which way it was facing originally. You can use the putty knife to remove any glue remains that were left over from the previous thermostat. Once the surface is cleaned, apply the new glue to the gasket and insert the new thermostat in the same manner as the original you removed. Allow it to remain in place long enough for the glue to set. Once it is firmly in place you can reapply the housing and bolt it back into place just as you found it.

Step 4 – Replace the Coolant

The last thing to do is refill the radiator with appropriate coolant (anti-freeze and water mixture.) once you have the new coolant filled in the radiator you can cut the car back on to make sure the thermostat is accurately measuring the engine’s temperature. Be sure to monitor the temperature and make sure it is responding appropriately before you drive the vehicle on any long trip to avoid damaging the engine.