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Why is it blowing off oil cap

Cap keeps blowing off

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Too much crankcase pressure for some reason? I've seen a melted piston cause so much crankcase pressure, it blew the pcv valve out of the valve cover and sprayed oil all over the engine compartment.

Is your oil cap threaded? If it is threaded, I don't think I've seen one of them blow off? Also, check crankcase ventilation system, pcv where applicable. Do you have a lot of blow-by from crankcase? I don't know your year--make--model or engine size?

Posted on Nov 22, 2014

  • Kevin chisenhall Apr 26, 2015

    Sounds like you have broken rings or a bad head gasket and maybe a cracked head.



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