Re: E30 M3 sudden oil leak

[Jefrem Iwaniw <jiwaniw@xxxxxxxxxxxx>]

Hi John,

Many times, it will appear that the leak is coming from "the small gap
between the bell housing and the engine" when in fact its origin is
someplace else.  This junction is one of the lowest points on the
drivetrain, and leaks from other parts of the engine will run down the
side of the block (or wherever) to this point before dripping to the
ground.  Now, my experience in this area is from my '02, whose M10 engine
shares many characteristics with your S14, but it is very different in
many ways also, so this advice may not apply.  However, it can't hurt, and
is alot easier than replacing the rear main seal :=).

Check the following:

- -oil pressure sender -- these can start to leak
- -distributor mounting case (if you have one) -- check that all fo the
bolts are correctly torqued
- -exhaust manifold nuts/studs - check to make sure that they are all seated
correctly

I'm sure the E30 M3 owners will chime-in with other suggestions.  Good
luck!

- ------------------------------------
- -Jefrem Iwaniw, jiwaniw@domain.elided, '72 2002, '94 525i
 Keller, TX


On Wed, 2 Dec 1998, John Masles wrote:

> I know what the likely answer is, but I'm looking for alternatives ....
> 
> My 88 with 72k miles on it went from a drip of oil every few days to
> a 2 inch puddle each day. This occured virtually overnight and wasn't
> the result of any unusual activity ( no missed shift ). I've been underneath
> and the leak is out of the small gap between the bell housing and the 
> engine. Is there any chance that there's a plug in the back of the engine
> that started leaking? Or perhaps a stuck oil pressure regulator that is 
> causing a boost in oil pressure?  
> 
> The previous owner had the seals ( including rear main ) replaced 3 yrs 
> ago ( maybe 20k miles worth ). It started leaking after a year or so with
> Mobil one 15-50. I switched to Redline 20-50 a year or so ago, and noticed 
> a significant reduction in leakage ....
> 
> T.i.a.
> 
> John. 
> 

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