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Q: Bad thermostat causing radiator leak.

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My radiator has a severe radiator leak. I suspect it is at the overflow reservoir and is being caused by a bad thermostat.

Just to be informative the radiator and the overflow tank are two separate parts that both store coolant and if one is leaking the other is not leaking. Also a bad thermostat will not cause a radiator or an overflow tank to start leaking. If one of those two parts are leaking and the leak is not obvious to the eye I would recommend having a technician perform a cooling system pressure test to determine where your leak is located. This test pressurizes the cooling system without the engine running making leaks more easily noticeable to the technician. Once the leak is found I would recommend having it repaired as soon as possible in order to prevent engine damage due to overheating.

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