Audizine - An Automotive Enthusiast Community

Results 1 to 6 of 6
  1. #1
    Registered Member One Ring
    Join Date
    Dec 16 2017
    AZ Member #
    411228
    Location
    Oregon

    Oil leak from gasket on rear head

    Guest-only advertisement. Register or Log In now!
    Hi all I just replaced the water pump on my 2012 A4. While I was at it I re-sealed the valve cover since it was leaking. Now the gasket a the rear of the exhaust cam leaks that drives the high pressure fuel pump. Its a milti-plate metal gasket with three holes. Anyone have a part number for this or know what it would be called? Thanks for your help.
    -Nate

  2. #2
    Established Member Two Rings Quattro420's Avatar
    Join Date
    Apr 08 2015
    AZ Member #
    325740
    My Garage
    2003 Jetta tdi 5peed 2000 b5 a4 1.8t 5aq, 2005 Passat tdi wagon2.0l, 2000 sierra 5.3l
    Location
    Ontario Canada

    Vacuum pump gasket

  3. #3
    Active Member Two Rings
    Join Date
    Jun 17 2018
    AZ Member #
    420830
    Location
    Colorado

    Agreed w/ Quattro420. Also, you can either replace the pump, or take it off, drain out the oil from where it shouldn't be, reseal it, and put it back in.

    Here is the reseal kit.

    If you do the reseal, note that when putting the pump back on, you need to use the old gasket and replace just the one layer of it with the new supplied gasket (otherwise you won't have enough gasket and it will leak really badly).

    You can also buy a new version of the gasket that (typicals) stays captive on the back of the when removing the vacuum pump. I think this is it, here.

    And here is the pump itself, should you want to replace it (this is Audi's recommendation, they frown on reseals).

    Cheers,

  4. #4
    Active Member Two Rings
    Join Date
    Jun 17 2018
    AZ Member #
    420830
    Location
    Colorado

    Oh and here's a video on how to do the reseal. Note that this is a different pump than what's on the (MY09) B8 A4. But it's similar and gives you an idea.

    Here's what MY09 looks like:





    And here's the seal that typical fails (almost always):


    My understanding is that the pump was intentionally made out of two different metals (the body, and the lid), such that if/when oil fills into the spinning part that generates the vacuum, it would leak out. I think the goal in designing it to leak was two-fold:
    1. It prevents the pump/brake system from producing no vacuum at all - which could be bad, I think - because the brakes would be not very effective. I think it would be like the car is off.
    2. To let whoever services the car know that the vacuum portion of the pump is filled with oil, and should be fixed.

  5. #5
    Active Member Two Rings
    Join Date
    Jun 17 2018
    AZ Member #
    420830
    Location
    Colorado

    Oh and note that the high pressure fuel pump is driven directly off of the rear section exhaust camshaft (I think you already know this, but for others who may read this), and the exhaust camshaft actually resides inside the brake vacuum pump. The fuel pump 'Roller Tappet' rolls over this section of the camshaft, within the vacuum pump assembly.

    That is to say, be careful when you do this job.

    Number 6 on the diagram is the little tappet that you can see in the background of the photos above (#7 is the vacuum pump itself):


    And that tappet rolls over the back of the exhaust camshaft (the rounded-square portion; #9 on the diagram):


    Cheers!

  6. #6
    Registered Member One Ring
    Join Date
    Dec 16 2017
    AZ Member #
    411228
    Location
    Oregon

    Thanks guys for the information. Yeah it had the capture style gasket and i put a little rtv where the factory blue sealant was there but seems like it didn't go together well. Are you guys saying the outer oring is the main culprit? If that's the case ill just pull the whole thing off again and re seal it and get a new pump roller. Last question, know the torque on the main 3 bolts that secure it to the head, i guessed 4 N/m.

    To put it on i first removed the high pressure pump and the cam follower. Got the vacuum pump bolted on then reinstalled the cam follower/ fuel pump. Was a super pain to try and get the roller on the cam otherwise.



Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  


    © 2001-2018 Audizine, Audizine.com, and Driverzines.com
    Audizine is an independently owned and operated automotive enthusiast community and news website.
    Audi and the Audi logo(s) are copyright/trademark Audi AG. Audizine is not endorsed by or affiliated with Audi AG.