N55 cylinder headgasket leaking

image We don’t see this very often on a N55 about 25k miles,,,,the cylinder head gasket leaking oil,,,,leaking from the rear of the head by cylinder 6,,,this was a pretty good leak at that,,,,running down the rear of the engine and on to the ground,,,,it first looked like the oil pan gasket was leaking,,,,but upon further investigation we noticed it was coming from the cylinder head.image This job is a lot easier with the motor and transmission completely out of the car,,,,it makes it easier to remove the cylinder head and remove the turbo assemble,,,,instead of fighting it inside the car.image Here the cylinder head is removed,,,and if you look at cylinder 6 at the bottom triangle hole in the engine block,,,,,you can see where the cylinder head gasket started to leak,,,,see the dark coloration .image Now here is the cylinder head,,,,again you can see the dark coloration where the head gasket and the oil started to leak out,,,,there was no damage to the head or engine block,,,,so we just have to clean up the cylinder head and engine block and replace the headgasket and head bolts and misc gaskets.

This entry was posted in Uncategorized and tagged , , , . Bookmark the permalink.

14 Responses to N55 cylinder headgasket leaking

  1. F30ed says:

    You had to remove the engine and tranny out of the car to do the work? How much labor was it? It must be thousands if no warranty….


  2. Jeff says:

    I know it’s an older post, but is an failing headgasket an common issue on the n55 engine.


    • No it doesn’t happen that often,,,,kind of rare


      • Jeff says:

        Thank you for anwsering my question.
        I was Always wondering, is there a special cleaning methode for the cil block and head?
        and the aluminium head bolts, are they mounted dry or need they to be lubed before installing them?


      • You special cleaning procedure,,,,you can clean it with brake spray or carb spray,,,,what ever to get all the dirt and oil off the mating surfaces,,,,you have to get all the old headgasket stuff glue off the head and block,,,,,clean out the head bolt holes of water and oil,,,,,the head bolts are made of steel not aluminum .


  3. Richard Hernandez says:

    This is becoming more of a issue as these cars get older. I have seen 3 this month. Haven’t fixed one yet though.


  4. Paulo says:

    Hi, I’m experiencing a issue with my 2011 335i. The cooling system is getting pressurized and I think it’s a loose head bolt. It’s EXACTLY THE SAME issue that is described in this post at 1addicts http://www.1addicts.com/forums/showthread.php?t=1331161&page=7
    Maybe it’s an assembly error at BMW, coincidence or not, my car was assembled in April 15th 2010 and the car in the thread was assembled in April 16th 2010. Have you experienced more n55 engines with a loose bolt near de 6cyl?

    Thank you for your time.


  5. H says:


    Jan 2010 F07, N55. I had, 2 bolts cylinder 5 and 6

    Liked by 1 person

  6. Pingback: Bmw N55 – free

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.