Announcement

Collapse
No announcement yet.

New inlet manifold gasket is leaking

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • New inlet manifold gasket is leaking

    Today I finished the seal replacement on the water manifold with good success.

    In order to get to that I had to remove the IM.
    I refitted the IM with a new gasket but it's leaking from cyl 1 to 5.
    It doesn't make sense, does it need to set for a while?

    The bolts were tightened to 20 Nm.
    The mating surfaces on IM and head were carefully freed of old gasket remnants.

    I just don't understand were I went wrong.
    Should the bolts be tightened in some particular order?
    Don't remember how I did it when I first built the engine.

    Need to pull the IM again tomorrow but it would be nice to know what in the heck I did wrong.
    Audi S2 -1994 | 480 Hp 650 Nm | FlexFuel | MaxxECU | 3" Stainless | Porsche GT3 Front Brakes
    http://www.garaget.org/?car=52877

  • #2
    The old gasket (leak free) was from a Victor Reinz kit and the newly fitted came from Audi Tradition.
    Fortunately I have one more spare in the garage which is also Victor Reinz.

    It'll be interesting to see if there's any differences.
    I doubt it since other gaskets bought from AT has had Victor Reinz stamped on them.
    Audi S2 -1994 | 480 Hp 650 Nm | FlexFuel | MaxxECU | 3" Stainless | Porsche GT3 Front Brakes
    http://www.garaget.org/?car=52877

    Comment


    • #3
      I'm starting to doubt my previous statement that the old gasket was leak free.

      To answer my own question though, yes the AT and VR gaskets are different.
      OEM is paper core and VR is aluminium core and about 0.1 mm thicker.

      However my problem persists and most likely have been an issue since building the engine.

      I have now tried it with various gaskets and it still wont hold pressure.
      Had them IM flange machined so it should be straight and true, removal was ~0.15 mm.
      Also by hand tool carefully attempted to get the head flange straight.

      Despite all this it is still leaking.

      I guess pulling the head and get it machined is the obvious and best answer but what else can I try first?
      I'm thinking of getting some inc or paint on the IM flange and fitting it to the head to see where the contact points are and what is causing the issue.
      Probably grasping at straws here but it seems that the protruding injector inserts makes the biggest imprints on the gaskets, could these att to the issue?
      Should I trim them down?

      Any other 'redneck' tricks I can use?
      Double gaskets? Gasket sealer?
      Audi S2 -1994 | 480 Hp 650 Nm | FlexFuel | MaxxECU | 3" Stainless | Porsche GT3 Front Brakes
      http://www.garaget.org/?car=52877

      Comment


      • #4
        Adding pictures.

        Inlet manifold flange:
        machined flange.jpg
        Different gaskets, top OEM (Audi tradition), bottom Victor Reinz:
        gaskets.jpg
        Audi S2 -1994 | 480 Hp 650 Nm | FlexFuel | MaxxECU | 3" Stainless | Porsche GT3 Front Brakes
        http://www.garaget.org/?car=52877

        Comment


        • #5
          Originally posted by k.alle View Post
          I guess pulling the head and get it machined is the obvious and best answer but what else can I try first?
          I can't imaging that this face has warped?...….and unlikely to be incorrectly/poorly machined from new? If it is corrosion free I'd be for taking a straight edge across it to confirm it's true.
          Are you confident that the bolts you're using to secure the manifold aren't bottoming out ? (too long?)

          If sealer is used I'd be very carful not to use too much, I'd be apprehensive about using sealer.

          Comment


          • #6
            Thank for the input John, much appreciated.

            I'm having trouble understandig it myself.
            It is a 7A head so I'm not sure if that face is different in any way from the Turbo versions.
            The ABY head is still with me so I could cross reference but not sure what method to use.
            IF that face is not true, what is the best method for me to get it true in situ?
            Using files? sandpapers?

            I've measured the bolts vs holes and they should not bottom out but I could try using M8x25 instead of the M8x30 from factory.

            I failed to mentioned that I actually tried using a sealer+gasket before getting the IM flange done and that also leaked.

            Audi S2 -1994 | 480 Hp 650 Nm | FlexFuel | MaxxECU | 3" Stainless | Porsche GT3 Front Brakes
            http://www.garaget.org/?car=52877

            Comment


            • #7
              Are the injector seats all the way in? Difficult to see from pic but are they proud?
              Is the IM surface good?
              You can use glass plate and fine emery to clean up surface.
              Last edited by Tractor Dave; 1 June 2020, 12:09.
              Nothelle S2 Avant
              Black Ur project
              Ocianic Ur project gone
              S2 Coupe project gone
              Urs6 plus project gone

              Comment


              • #8
                What pressure are you up to during testing?...….I'd be for nipping the bolts up a bit more than the 20Nms ?

                Comment


                • #9
                  Originally posted by Tractor Dave View Post
                  Are the injector seats all the way in? Difficult to see from pic but are they proud?
                  Is the IM surface good?
                  You can use glass plate and fine emery to clean up surface.
                  The injector inserts/seats are all the way in and they protrude a little bit on the head side.
                  IM surface is good, just had it machined at a workshop which didn't help unfortunately.

                  Glass plate sounds difficult to handle in that tight space in the engine bay. Maybe I'm imaging it wrong..

                  Originally posted by John. View Post
                  What pressure are you up to during testing?...….I'd be for nipping the bolts up a bit more than the 20Nms ?
                  Around 1 bar.
                  I've tried torqueing them to 23 Nm and at one point also added more without torque wrench. Maybe up to ~30 Nm.
                  Didn't help.


                  This issue is so frustrating and time consuming bolting everything up, pressure test and tearing it down.
                  Audi S2 -1994 | 480 Hp 650 Nm | FlexFuel | MaxxECU | 3" Stainless | Porsche GT3 Front Brakes
                  http://www.garaget.org/?car=52877

                  Comment


                  • #10
                    "The injector inserts/seats are all the way in and they protrude a little bit on the head side."
                    I would remove them and check the threads are clean. Are they the right ones? They shouldn't be proud.
                    Nothelle S2 Avant
                    Black Ur project
                    Ocianic Ur project gone
                    S2 Coupe project gone
                    Urs6 plus project gone

                    Comment


                    • #11
                      Maybe the IM flange also has had work done before I owned it, thus making the flange thinner and the inserts protrude?

                      Interesting though, as I mentioned earlier I can see on the gasket that the inserts are making significant imprints on the gasket when tightened down. Was not sure if it is normal or not.

                      I cleaned the threads after machining of the flange so they are nice and clean.
                      The parts are new from Audi Tradition, part: 034133555.
                      Last edited by k.alle; 1 June 2020, 14:23.
                      Audi S2 -1994 | 480 Hp 650 Nm | FlexFuel | MaxxECU | 3" Stainless | Porsche GT3 Front Brakes
                      http://www.garaget.org/?car=52877

                      Comment


                      • #12
                        You could try taking a little off each insert so the don't protrude.
                        Nothelle S2 Avant
                        Black Ur project
                        Ocianic Ur project gone
                        S2 Coupe project gone
                        Urs6 plus project gone

                        Comment


                        • #13
                          Thanks I'll try that.
                          I'll just shave them off with a sharp knife or something.

                          Can I reuse a gasket that only has been installed once for 30min?
                          Or are they expended once clamped down?
                          Audi S2 -1994 | 480 Hp 650 Nm | FlexFuel | MaxxECU | 3" Stainless | Porsche GT3 Front Brakes
                          http://www.garaget.org/?car=52877

                          Comment


                          • #14
                            No, I don't think a knife will do. You will need to use a grinder but be careful not to remove too much. If you are taking off the bottom, thread a nut on to use as a guide and you may have to file the threads a little so they 're seat again.
                            if you have a new unused gasket that will be best. If they are marked by the inserts it probably won't seal.
                            Nothelle S2 Avant
                            Black Ur project
                            Ocianic Ur project gone
                            S2 Coupe project gone
                            Urs6 plus project gone

                            Comment


                            • #15
                              I'm not sure I am understanding you correctly.
                              Are you saying I should take them out from the IM and thread a nut onto the insert?
                              Don't think I have nuts with those threads or know where to get them.
                              Maybe it's the language barrier tripping me up, sorry if I seem a bit slow.
                              I really appreciate the help provided.

                              I was thinking cutting, filing, sawing off the protruding bit while still in the manifold so that is flush or slightly below the flange surface and do my best not to hurt the flange.
                              Audi S2 -1994 | 480 Hp 650 Nm | FlexFuel | MaxxECU | 3" Stainless | Porsche GT3 Front Brakes
                              http://www.garaget.org/?car=52877

                              Comment

                              Working...
                              X