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Replace A Faulty Thermostat In A Vehicle.

    Drain And Wash The Cooling System: Make sure your vehicle is parked on level ground. Wait until your engine is cool off before working on any part of your vehicles coolant system. The cooling system of the vehicle should be drained and cleaned before changing the thermostat.

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    Remove The Thermostat Housing: Use a screwdriver or pliers to remove the radiator hose attached to the housing by pulling off the clamp. Then twist the radiator hose to loosen it from the radiator housing. An empty bucket should be placed under the vehicle because a considerable amount of coolant will pour out when the hose is been taken off. Then loosen the bolts on the thermostat housing using the appropriate sized open-ended wrench or ratchet socket and lift the cover off, then remove the thermostat. A clean rag should be temporarily stuffed into the thermostat opening on the engine while the housing is removed, to help keep debris out of the cooling system.

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    Installing The New Thermostat: Remember to look at how the thermostat is positioned before removing it, so as to be able to put it back the same way. Install the new thermostat and ensure the copper heat sensing element it towards the engine. It won't function properly if installed upside down.

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    Clean The Gasket Surface: The accessible parts of the water jacket should be inspected, carefully remove any thick crusted corrosion and ensure it does not drop inside the water jacket. Use the knife to remove the old gasket from the thermostat housing, place new gasket and tighten the housing. Ensure that the thermostat bolts are properly torque according to the manufacturer’s recommendation.

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    Refill The Cooling System: Re-fix the hoses and put the engine coolant back into the vehicle. Run the engine to full operating temperature when everything is back in place, check for leaks and also ensure that air has been removed from the cooling system.

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    Test Drive: Try to test drive your car to ensure that the temperature gauge needle stays at normal when the car is at full operating temperature. After test driving your car, make a final inspection of coolant level and leaks. 

Videos Edit Videos


  • Edit Tips Make sure you gather all the tools and supplies needed before you begin.
  • Edit Tips Allow yourself plenty of time to do the job so you can get a good result.


  • Edit Warning Safety is always important whenever you're working around machinery. Beware of sharp instruments, hot objects and hazardous materials.

Sources and Citations

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