Engine Valve Cover Vent Hose Necessary?

Discussion in '1994 - 1995 Specific Tech' started by dstang01, Jul 2, 2012.


  1. dstang01

    dstang01 Member

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    Hey folks, doing a head swap and my new valve covers don't have a fill neck with a nipple for the vent hose. Should I look for a cap with a hose or would I be fine deleting it? Doesn't the PCV take care of venting?
  2. revhead347

    revhead347 I have face herpes.

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    The PCV valve is where it goes out of the crank case, you need a vent for fresh air to come in. It doesn't have to be a hose, you can use a breather cap.

    Kurt
  3. dstang01

    dstang01 Member

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    Thanks, I picked up something like this from the parts store and it should work!

    [​IMG]
  4. revhead347

    revhead347 I have face herpes.

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    Does that have a breather element in it, or is it just a baffle? If there is no breather filter inside of it, that nipple has to be connected with a hose back to the intake.

    Kurt
  5. HISSIN50

    HISSIN50 "How long does it take to get help in here? SN Certified Technician

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    You might also want to take metered air into consideration if you don't keep the system closed..........
  6. revhead347

    revhead347 I have face herpes.

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    I know this is a technicality that is a correct consideration, but in all honesty I've never seen it be enough air to make any difference.

    Kurt
  7. dstang01

    dstang01 Member

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    It's baffled and I ran 1/2" heater hose from it to the nipple on the intake, still a closed system. It actually looks great with classic chrome valve covers :)
  8. toyman

    toyman Active Member

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    Really. That's like a big vacuum leak. I wouldn't be surprised if many surging idle issues are caused by adding unmetered air into the equation.
  9. revhead347

    revhead347 I have face herpes.

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    I would tend to agree with you given the size of the hole in the PCV valve, but I've never seen it make a difference.

    Kurt
  10. k00ksta

    k00ksta Member

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    un-metered air is always bad business from what I have seen. But maybe its not enough to cause issues.

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