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    Potential Valve Sealing Issue

    History:
    Warped head, mixed oil and coolant everywhere. The head had a ton of miles on it, so I figured why risk potentially having damaged other things when it overheated, so I purchased a rebuilt head. This is the ebay listing for it.

    Got the head, it looked great. Bolted it on, things seemed fine. Could not get the car to start, but it would turn over. Tested spark, tested fuel, tested CPS, confirmed timing...all good. Did a pressure test and got the following:

    80 30 15 30 0 100

    Obviously that is pretty concerning, but why 0...that is odd. Did a leakdown test. On every single cylinder expect the one that got 100 PSI on the pressure test, I have a MASSIVE exhaust leak out the headers (do no have the rest of the exhaust fabbed up). If I plugged that, there was a small, but noticeable leak on the intake side. I made 100% sure that there was no lift occurring and that for each cylinder I was at TDC such that the intake and exhaust valves were closed. Overall, I was putting in 110 PSI and getting 10-15 back. It was that bad. I popped the head off thinking that the valve seats were blocked in some way or something was causing the valves to not to seat properly. Visually, the head looks great. It looks brand new. The seats and the valves are clean and pretty. All cylinders while at TDC seemed to have fully closed valves. Also, not that this is scientific, but light would not penetrate a closed valve.

    So, if things seem visually good, what would be causing that massive of an exhaust leak on what should be a well built head that was supposedly pressure tested? I am kindof at a loss of what to do. I think I will drop some fluid in the exhaust ports and see if any leaks out of the valves (closed and no lift). Aside from that, my only other thoughts are to send it somewhere to be rebuilt, but as it is new, I really do not want to. A coworker suggested some valve dye to see how the valves sit up against the seats. I have never done that, so I am not sure how successful that can be.

    I'm a lot of what could be going on. I have exhausted my knowledge and troubleshooting abilities at this point. Thanks!


    1989 325i Alpine White
    69 STX

    #2
    Immediately start a PayPal claim.
    ACS S3 Build / Dinan 5 E34

    Comment


      #3
      How flat is the deck? What head gasket did you use? Did you put any sealer on the head gasket? any issues between the cylinders with the low pressure?
      What head gasket bolts? Did you use new bolts? did you torque them properly? Did you get the timing belt on correctly? Lots of other information. If you got the timing wrong and turned it over even once, you could have bent valves.

      Comment


        #4
        Originally posted by ahlem View Post
        How flat is the deck? What head gasket did you use? Did you put any sealer on the head gasket? any issues between the cylinders with the low pressure?
        What head gasket bolts? Did you use new bolts? did you torque them properly? Did you get the timing belt on correctly? Lots of other information. If you got the timing wrong and turned it over even once, you could have bent valves.
        How flat is the deck?
        Visually, good. A level also looks good, but I feel like how level the decking was comes down to measurement beyond what I can visually see.

        What head gasket did you use?
        Ireland Engineering

        Did you put any sealer on the head gasket?
        No. The gasket has some 'sealer' on it. That little red line of stuff around it. I do have gasket sealer though I could put around it.

        Any issues between the cylinders with the low pressure?
        Not that I am aware of. Visually good. Also, block ran very nice for a few years in my possession. Crosshatching and all that on the cylinder walls looks nice.

        What head gasket bolts?
        ARP Head Studs

        Did you torque them properly?
        30ftlb then 90 deg and 90 deg. Proper pattern each time also. So yes, torque properly.

        Did you get the timing belt on correctly?
        Yes, by now I have probably checked that 6 times. Someone else also verified for me. TDC on cam and crank. Belt is tight. I've changed E30 belts a few times successfully, so I'm confident it is correct.

        Bent valves scare me as I could have received it that way. I do not think that me cranking the motor over did any damage as timing is correct and I assume I would hear a nasty collision noise if that were the case.


        1989 325i Alpine White
        69 STX

        Comment


          #5
          Don't see it mentioned ,but you did adjust valves after installing head right?

          Sent from my SM-G360V using Tapatalk
          Angus
          88 E30M3 X2
          89 325IX
          92 R100GS/PD
          :)

          Comment


            #6
            Originally posted by spdracrm3 View Post
            Don't see it mentioned ,but you did adjust valves after installing head right?

            Sent from my SM-G360V using Tapatalk
            I did! Thanks for reminding me. They were not properly adjusted when I got the head. There was no gap whatsoever, so I did that to factory (.010).


            1989 325i Alpine White
            69 STX

            Comment


              #7
              If set correctly then something has to be wrong with seats/valves or the seat concentricty to guide .as head is off flip it over so valves are facing up and with sparkplugs installed fill combustion chamber of each cyl with valves closed with solvent and look for leakage into ports.shouldn't be any if seats/valves were cut properly.
              Also inspect valve and seat contact surface of open valves for signs of debris that could be holding valves open

              Sent from my SM-G360V using Tapatalk
              Angus
              88 E30M3 X2
              89 325IX
              92 R100GS/PD
              :)

              Comment


                #8
                Originally posted by spdracrm3 View Post
                fill combustion chamber of each cyl with valves closed with solvent and look for leakage into ports.
                That is my next step. They look clean of debris.


                1989 325i Alpine White
                69 STX

                Comment


                  #9
                  Think it got set down on the open valves?

                  t
                  now, sometimes I just mess with people. It's more entertaining that way. george graves

                  Comment


                    #10
                    Originally posted by MisterMiniS View Post
                    Did you torque them properly?
                    30ftlb then 90 deg and 90 deg. Proper pattern each time also. So yes, torque properly.
                    the answer is NO, you did it wrong.

                    Studs are not torque to yield.
                    you do 25lbs, 45lbs, 62lbs.

                    then we move to the head. did you build the head back up while it was sitting on a bench? did you support it with blocks of wood so the valves do not touch the ground?

                    anyways this was done wrong. take it apart and start over.
                    pressure test the head always, before installing.
                    Much wow
                    I hate 4 doors

                    Comment


                      #11
                      And to make perfectly clear, you adjusted the valves WITH the head torqued down completely correct? Not just "on the bench".
                      ADAMS Autosport

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