BimmerFest BMW Forum banner
1 - 2 of 2 Posts

·
Registered
Joined
·
40 Posts
Discussion Starter · #1 ·
Ever since I got the car the oil filler cap has been leaking oil. First thing I did was replace the oil filler cap with a new one from the dealer - no change still leaked.
The valve covers were severly flaking and crusty around the oil filler cap. I had the covers sandblasted and powder coated and it is still leaking. I then thought that maybe the powder coating was uneven and causing oil to seep out of the cap so I sanded off the poweder coating aournd the cap and that sh*t is still leaking. I then bought another cap and took the seal from that cap and combined it with my existing cap to form a pretty snug fit...seems a bit better but oil still seeps out..

It leaks so bad that after a long drive there is oil dripping the side of the cover and it has been sprayed (by the fan I guess) onto the air filter housing.

Anyone have this issue, searches don't turn up much.

Is it time to break down and buy a new valve cover and another cap (I guess?) and be done with it...or could it be something else.
 

Attachments

·
Registered
Joined
·
150 Posts
As engines age, there is an inevitable rise in blow-by gases as the piston rings don't seal as well. If the amount of blow-by is more than the PCV can handle, it will pressurize the inside of your case and can worsen oil leaks, including forcing oil past your filler cap gasket.

Maybe your engine has too much blow-by gases or your PCV is stuck shut. Do an easy test for blow-by gases:

- with the oil filler cap off, hold your hand above the filler opening and have someone start the engine (being ready to turn it off right away on your signal if necessary)

- if you feel a pulsating pressure of air coming out of the filler opening, something might be wrong with either your PCV or your piston rings or maybe both. If things are really bad, oil can be blown out with the air flow, too.

Walter
 
1 - 2 of 2 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top