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Rough Running

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  • Rough Running

    We had an engine non Studebaker, that was disassembled and new gaskets, plugs, wires, this engine was injected and therefore confirmed injectors. After assembly there was a subtle ripple similar to a vacuum leak some where, no leak could be determined and we lived with the ripple. As time passed the engine blew a head gasket and we pulled the engine, disassembled it and found two cracks between two sets of valves. In hind sight I suppose a leak down test may have determined the problem, but never-the-less the engine had to come apart. That engine is scrapped and a new one is replacing it. The condition was very difficult to diagnose as it was very subtle also the spark plug for one of the cracked heads was very clean near white and looked quite normal whereas all the others had limited amounts of oil residue. The only confirmed diagnosis was disassembly and seeing the crack, that answered all the questions.

  • #2
    Would another way to say the malfunction be to say: "it was a Miss"?
    Usually those can be detected in the Exhaust or Intake sound.

    So No Coolant loss?
    Cracks in Both Heads or all in one?
    If both in the Right Head, Sometimes Exhaust System/Combustion Chamber overheating is caused by a stuck closed Heat Riser Valve, if operated at sustained high speed.
    Second Generation Stude Driver,
    Proud '54 Starliner Owner
    SDC Member Since 1967