What Happens When the Thermostat Goes Bad?

Your SUV, car, or truck relies on the thermostat to keep the engine cool. The thermostat doesn’t actually cool the engine itself, but it does release the coolant for the water pump to circulate. The thermostat does this by reading the engine’s temperature and determining when it gets too hot.
On average, you can expect to get about 10 years or 100,000 miles of service out of the original thermostat. After this time, the thermostat could start to leak and/or malfunction and create problems in the engine, especially with the temperature. Let’s talk more about this below.

Corroded Thermostat

If the thermostat starts to leak, it will start with a slow leak most likely. This is a leak out of the valve that the thermostat opens to release the coolant. This valve can allow the coolant to seep out of it and pool around the thermostat and its metal housing. The coolant will turn gel-like and start to corrode any metal associated with the thermostat. It’s best to replace the thermostat if it is corroded so you don’t end up with a larger coolant leak.

Leaking Engine Coolant

Not a very good segue, but let’s talk about this larger coolant leak. If the coolant keeps eating away at the thermostat and its housing, you will end up with a puddle of coolant on the garage floor. This will reduce the coolant level in the engine, naturally, and leave you with a hot engine when you try to drive your automobile. You can add coolant to the cooling system, but it will leak out of the thermostat, as well. It’s best to replace the thermostat.

Strange Temperature Changes

The thermostat can also malfunction when it gets too old. It may or may not leak, so keep in mind that you may still have to replace the thermostat even if it isn’t leaking. If the thermostat starts to misread the engine’s temperatures, it will release the coolant at strange times. Consequently, you will see your temperature gauge needle going up and down constantly. This is a sign that the thermostat is malfunctioning and cannot determine the engine’s temperature correctly.

Overheating Constantly

Finally, the thermostat may stop working altogether and this will leave you with an overheating engine no matter how often you drive your automobile. In fact, the engine will overheat quickly, within 10 to 15 minutes after you start the automobile.

Call us today if you are having problems with your vehicle’s thermostat. We can test the cooling system part and replace it if necessary.

Photo by pandemin from Getty Images via Canva Pro