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How do I fix my car thermostat?


Here is your tasty information and answers to cars DIY question on “how do I fix my car thermostat?” and 5 simple easy steps to fix any car’s thermostat in a short time. When a car is always give over heating problem, it is most probably time to check out on the thermostat and get it replaced. It is important to know what a thermostat do, where is it located, and how to find out it is not working before changing a car thermostat.

Car thermostat replacing is something easy to DIY (Do-It-Yourself) even though you never did it. All you need is a suitable place, correct tools, and the steps to complete this simple task less than an hour.

Step 1 – Prepare all needed parts and tools

Prepare all tools and parts needed such as wrenches, screwdriver, nut drivers, socket, drip pan, gasket, sealant, and off course a new thermostat according to your car make, model and year.

Step 2 – Remove the old and worn thermostat

Remove or unscrew the clamp that attaches the water hose to the engine. Pull the top hose out from the engine slowly by twisting it a little bit if it is too tight, and then you can simply take out the thermostat. Loosen the bolts or nuts that hold the thermostat housing. Here you can simply take out the worn thermostat.

Step 3 – Clean the fixing area

Check if the top hose has worn out, if yes you can also buy a new one to replace since you have already removed the top hose. Clean up the old sealant that stuck between the housing and the engine. Do not skip this step as cleaning is important for new thermostat to work better.

car thermostat diagram

Step 4 – Installing the new car thermostat

Now replace the new thermostat by simply place it back to the location where the old one stands. Next is to spread some gasket sealant to all needed place, tighten the housing bolts and fix the top hose to the thermostat. Don’t you think it is simple?

Step 5 – Get the job done

Last is to wait until the gasket sealant totally dry up and refill the coolant that lost during your job. Start the engine to check if the new thermostat is working. If the temperature of the car engine goes fine, it is working and job done!

What does a car thermostat do?

A thermostat is a small metal, comparatively simple and one of the most inexpensive car parts for a car engine but it plays a very significant role in a car. So, what does a car thermostat really do?

  • It adjusts the engine’s operating temperature by controlling the flow of coolant from the engine back to the radiator.
  • It is a simple valve held shut by spring tension.
  • Thermostat’s valve open and close base on the coolant temperature. It opens when the engine heat up and allows coolant to circulate between engine and cooling system.
  • Thermostat will close when the temperature of coolant begins to drop after the circulation and cool off. This helps to speed up engine heat during cold days or winter.
  • Cycling open and close relatively constant will allow the engine’s operating temperature maintained at its best.

It is good to know what a car thermostat really do before replacing or installing a car thermostat. It will be good to know the function and the jobs before you ask how to fix the thermostat. It is important to buy the correct thermostat or recommended unit because wrong unit will produce wrong temperature.

Where is a car thermostat located?

A car thermostat usually located in a housing where the upper radiator hose is connected to the engine and another end of the hose is connected to radiator.

How do I know if my car thermostat is not working?

The most common sign or hints your car will give to you when the thermostat is not working or going bad is the car engine temperature. The car will tell you through the temperature gauge by showing high temperature or so called “over heating” (usually more than half of the gauge and reached the red zone).

Another way to check if the thermostat is stuck shut is start up the engine for few minutes until it heat up. Shut down the engine and check both water hose (the upper hose and lower hose). If one of it is hot and another stay cold, most probably the thermostat stuck shut and time to change.

It is very dangerous when a thermostat stick to close which means it blocks the coolant coming out from the engine for the circulation. It will make the engine overheat and may cause engine burn. For some countries that do not have 4 seasons especially winter, it is recommend to remove or simply throw away the thermostat. This is because hot tropical country remains hot weather for all 365 days.

Check out also some related articles such as Ford fuel filter replacement, How do I get my car on overhauling, and also How to upholster car seats. So, have you found the answer for the question “How do I fix my car thermostat?”
car thermostat


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