Pcv inside Breather?

Small Block Mopar Engine

  1. Kllrbee

    Kllrbee Well-Known Member

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    Im having a bitch of a time finding the proper sized grommet for the oil fill holes on the MP black wrinkle VCs. Im getting tired of it leaking. I figured Id just get the twist on breather, drill out the top and put the grommet and Pcv in it. Anyone see an issue doing this? I cant think of any, but thought Id ask.
     
  2. Kendog 170

    Kendog 170 Let the boy go !

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  3. lilfontleroy

    lilfontleroy annoyinglilLeroy

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    actually yes, IIRC the breather and PCV are supposed to be separated for proper engine "breathing", to that end I think you'll find that the breather goes on right (pass.side) VC and PCV goes on left (drivers side) VC and should connect to a front vac-port under the carburetor.
     
    Last edited: Jan 26, 2021
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    • dartfreak75

      dartfreak75 Restore it, Dont part it! FABO Gold Member

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      I don't know if it's the same size your looking for or not but I have some extras. I had a hard time finding them too for the factory size pcv so when I did find them I ordered extras. What are the dimensions of the one your looking for
       
    • Kllrbee

      Kllrbee Well-Known Member

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      Well the factory Pcv is .50" isnt it? Mine is .75"
      The issue is that none of the grommets are wide enough in their groove to seat properly. Apparently the MP Vcs are somewhat thick. Thats why Im thinking just get the twist on and be done with it. As of now, the Pcv is on the pass rear (oil fill hole) and connected to center carb. Id like to leave it there instead of using the knockouts for various reasons. There is no breather at this time.
      So what if I got 2 twist on breathers and put them each in their oil fill holes and installed the Pcv into one? That way Id have the breather on front driver which would also be used as the oil fill and the Pcv rear pass as it is now.
      I might be overthinking this...:)
       
    • Blind Squirrel

      Blind Squirrel Well-Known Member

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      Correct, you can't push and pull out the same hole at the same time. Although it was rumored Louise Armstrong could. One side has to pull vacuum so the other can allow atmosphere.
       
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      • CRUZE 418

        CRUZE 418 FABO Gold Member FABO Gold Member

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        Not everyone knows what your short cut in abbreviations means. I don't know what valve cover you are referring to.
         
      • lilfontleroy

        lilfontleroy annoyinglilLeroy

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        another IIRC ~ too much crank ventilation is as bad as not enough.. you're going to need someone who better understands the science to post in here
         
      • Kllrbee

        Kllrbee Well-Known Member

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        My bad...Mopar Performance black wrinkle. See pic.

        Youre right. Forget the 2 breather idea. That was me overthinking.

        20180825_142636.jpg
         
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        • Kllrbee

          Kllrbee Well-Known Member

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          Mine is 3/4" ID, 1" OD.
          The top lip needs to extend out over the oil fill hole cutouts though (where the tangs of the twist on cap goes). Ive read those are 1.22".
          Ill keep searching. Honestly surprised this is such a chore.
           
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          • CRUZE 418

            CRUZE 418 FABO Gold Member FABO Gold Member

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            Mancinni Racing has the grommets that you want. That's where I got mine, if you need the part # , I can get it when I go back out to the garage.

            20200908_180316.jpg
             
          • Blind Squirrel

            Blind Squirrel Well-Known Member

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            Last edited: Jan 26, 2021
          • Blind Squirrel

            Blind Squirrel Well-Known Member

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            Lets try this again.

            1-jpg.jpg
             
          • CRUZE 418

            CRUZE 418 FABO Gold Member FABO Gold Member

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            MRE 5249642 is the grommet #. You will need a breather for inlet on the opposite bank of the PCV Valve. Do your valve covers have any baffels under the two holes? You will need two of them, the screw mounts should already be in the roof of the covers if you don't.
             
          • Kllrbee

            Kllrbee Well-Known Member

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            Yup, thats exactly what I was thinking.

            Thanks, ill order them tonite. I already ordered the twist on type breather (#4529880). So ill just stick with that on drivers side and use the correct Pcv grommet on pass side. Just how you have in your pic.
            Already have baffles. Thanks again!
             
          • dartfreak75

            dartfreak75 Restore it, Dont part it! FABO Gold Member

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            I have heard of ppl having the same problem before. I think they stopped making them or something I can't remember. I will measure the ones I have and see if they are close if it will work I will send you one.
             
          • Kllrbee

            Kllrbee Well-Known Member

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            Thnx man.
            Ill hold off on the Mancini order then.

            As mentioned, my pcv is .75, but I can get a .50 from Napa if thats all you have. Just as long as I can get the grommet to seal properly in the cover, Ill be a happy camper.
             
          • lilfontleroy

            lilfontleroy annoyinglilLeroy

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            very nice!! seems to me the breather and PCV are switched around and I'm wondering if it matters? I have always been under the impression that crank ventilation was directly related to crank rotation.
             
          • Tooljunkie

            Tooljunkie King of cobble/master of the broken bolt FABO Gold Member

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            No, it only flows the other way south of the equator...
             
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            • Tooljunkie

              Tooljunkie King of cobble/master of the broken bolt FABO Gold Member

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              I found grommets for cast valve covers on the the edelbrock website. Ordered through amazon.
               
            • lilfontleroy

              lilfontleroy annoyinglilLeroy

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              :lol:
               
            • CRUZE 418

              CRUZE 418 FABO Gold Member FABO Gold Member

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              Probably better call the Chrysler Corp up and tell them that they did my '69 Dart wrong. The PCV Valve is on the pass side.

              20210127_081841.jpg
               
            • RedFish

              RedFish FABO Gold Member FABO Gold Member

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              Yes and no. Windage, everything in the crankcase moving same direction as crank, was considered in the beginning. So, air in on upper left, air out on upper right but... they fingered out that the vapor does have more oil still suspended in it on the right side, due to windage. Thats why the factory switched it, moved pcv right to left, in later models. I recall fords 5.0 having the pcv down in rearward center of intake but theres a fancy screen/separator beneath it.
              Advance Auto Parts - Down for Maintenance
               
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              • CRUZE 418

                CRUZE 418 FABO Gold Member FABO Gold Member

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                I would consider switching them, but the holes were already there, would make for a long hose in my case. Windage? Or acceleration, don't believe the crankshaft windage is getting up there, but can see oil piling up in the rear of the valve cover. Will keep an eye on my hose to see if it is overly wet. If these Mopar Performance covers ever came virgin, would have preferred the holes up front. Breather gets in the way of the heater hoses on pass side. My '72 318 has the PCV Valve on the drivers and breather on the pass side in the middle of the stock covers, and have a baffle that runs almost the length of the cover.
                It's always something!
                 
              • RedFish

                RedFish FABO Gold Member FABO Gold Member

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                Not drops of oil into the valve, more like molecules of oil carried by the vapor up into the right valve cover.
                 
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