Grants Pass Radiator Technician Suggestion on How to Tell if Your Thermostat is Stuck Closed

The thermostat of your vehicle is in place for controlling how much coolant gets released into the engine. When you first start your automobile, the thermostat will be closed, and no coolant would flow into the engine until it’s been warmed up. Only then will it open to allow coolant in. At times, the thermostat fails and will stay closed. How do you tell if this is the case? Follow along as we uncover some useful advice coming from expert Grants Pass Radiator technicians. Testing your radiator is well worth it, rather than the cost of radiator repair

Testing Your Thermostat at Home

You may want to blame your thermostat should the gauge marker near the red danger zone within 5 to 15 minutes. When this occurs, you need to turn off your car immediately and allow it to cool before opening the hood. Next, you will need to unhook the coolant reservoir and pour the antifreeze into it.

Find the radiator and take the cap off. Then, loosen the drain cock of the radiator that you will find near the bottom part to allow a bit of coolant to drain out into a container that has a lid on to just below the upper radiator hose. The amount you drain should be no more than 4 to 8 cups, which you can reuse it if it’s brand new.

Find the thermostat housing, which is typically underneath the upper radiator hose. You may just unbolt the housing before removing the thermostat with a screwdriver and pliers. Ensure you place the thermostat in a lit up area so you may establish what the opening temperature is that is normally between 160 to 190 degree Fahrenheit. Another way to find the right temperature is to consult your Workshop Manual.

Get yourself a pan so you may submerge the thermostat in the water without touching the bottom of the pan. At this point, you should begin to heat the water and put a cooking thermometer into the water. Frequently check the temperature while monitoring your thermostat. Ideally, the thermostat should open once it reaches the designated opening temperature that is stated in your Workshop Manual. What is more, the part should open fully once the water temperature is 10 degrees more than the suggested reading on your thermostat. If it is still closed, then you’ll know it needs to be replaced.

Testing Your Thermostat While on the Road

The minute you notice that your temperature gauge is nearing boiling point, which can happen unexpectedly and quickly, you need to turn your car off.

Step outside and wait until the hood is cool enough to touch before opening it.

Proceed with cautioning by touching the radiator hose carefully. Only do so for a few second to prevent scalding. The same principle would apply to the bottom radiator hose. If one of the hoses seems very hot and the other cold, then it is a sure sign that your thermostat is likely stuck in the closed position.

Testing Your Thermostat Using the Squeeze Test

Take your vehicle out for a short drive so you can warm up the radiator fluid.

When you return, open up the hood while the engine is still running. Wear an oven mitt or glove that is heat-resistant. Locate the top radiator hose, which would be the one that connects to the thermostat housing.

Gently squeeze the hose near the middle section as if you were attempting to shut it close.

Release it. You should experience a surge of water flowing through. Should the hose be too firm to squeeze, then it is a sure sign the thermostat is stuck closed.

But, what if the coolant that isn’t going through your car’s engine and you already had both the thermostat and radiator replaced? Grants Pass Radiator experts like Medford Radiator will recommend you consider replacing the water pump as it is another component that circulates the coolant through your engine. Their medford radiator service radiator repair shops, are high quality and provide the best value.

Needless to say, there is a host of other issues that may lead to an overheated engine such as poor mechanical timing, the need to replace engine coolant temperature sensor as these periodically fail, and the blower fan might be malfunctioning.

Because of this, you should strongly consider hiring trusted radiator technicians in Grants Pass such as Medford Radiator to sort out any heating issued with your radiator. Learn more by visiting

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