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Q: Pressure in the radiator hose after sitting all night on a '86 GMC Sierra 305

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I have an '86 GMC Sierra 305. I've noticed that my radiator hose have pressure in it the next day after sitting all night. Is that normal?

A: No, it's not normal. It should definite...

No, it's not normal. It should definitely cool down. Odds are your head gasket is starting to blow. I've got a video out there "how to tell if your head gasket is blown." Do that test and you'll see if it's blowing. It probably is. If you like the vehicle, I'd say get a head gasket job done. It's so old and those engines are so strong that it's worthwhile fixing it.

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