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Oil Pressure Relief Valve Fitment

Discussion in 'Norton Commando Motorcycles (Classic)' started by olympus, May 14, 2018.

  1. olympus


    Aug 5, 2017
    I note that on the OPRV the main body is sealed externally by a copper washer. Internally I cant see that the body seals against the casing... There is no washer listed & I didn't remove one.
    I have "blued" the end of the body and installed it, no marking fluid is transferred to the casing so it doesn't make contact here.
    Oil from the pump enters in the base of the OPRV body & lifts the spring, the oil exits though the holes in the side of the body & oil into the timing chest or oil inlet pipe (depending on what you have)
    The base of the hole in the timing case is also slightly dished, so the only physical barrier (as far as I can see) are the treads at the lower section of the OPRV,
    So am I right & should any sealant be applied to these threads to prevent "leakage" past

    Thank you
  2. rvich

    rvich VIP MEMBER

    Jul 25, 2009
    I don't run any on mine. But I have to admit I never thought much about it. If you loose oil past the threads, would it not be oil that was being dumped to waste anyway?
  3. comnoz

    comnoz VIP MEMBER

    Dec 10, 2008
    Yes, you are right. Quite a bit of oil leaks past the threads and it does reduce the oil pressure. I have assembled mine with anerobic sealer on the threads and it does raise the oil pressure -and makes them tough to remove. Comnoz
  4. olympus


    Aug 5, 2017
    Yes agree.. thanks Comnoz