Author Topic: Oil loss resulting form failed Timing Case Profile Gasket (Read 4196 times)

EricW · « **on:** November 10, 2012, 06:34:34 PM »

Hi All,
I have a mystery oil leak in my '91 318i, presumably a result of pressure as it doesn't seep when parked, so I'm thinking top end of the motor. Oil is visible on the front of the motor, behind and below the pulleys and front crank. The drips come off the bottom of the oil pan, obviously the low point. The previous owner, a BMW parts man, suggested it was a leaky profile gasket, but my reading and searches only seem to reference coolant leaks as a symptom of this failure. Curious your thoughts, if he could be correct and a slow leak in oil only could be a result of this failure or if he is making a presumption based on the history of failures in this part.
Thanks for your input.

deansweet · « **Reply #1 on:** November 10, 2012, 07:36:06 PM »

I'd look at the gasket/o-ring where the oil filter housing mounts to block.
Both of mine were leaking from this source.

-Dean

DesktopDave · « **Reply #2 on:** November 11, 2012, 09:02:32 AM »

+1 on that. You'll need to pull the alternator to get at it. Oil oozes out, flows down behind the mounting and around the oil pan flange until it drips off the lower pan.

deansweet · « **Reply #3 on:** November 11, 2012, 10:51:35 AM »

Some helpful info:
O-ring 24mmx3mm (15/16ths x 1/8th)
VICTOR REINZ Part # B32324 <-- Gasket
Torque specs are 7.1 FtLbs/89 InLbs on the housing. (10mm bolts to block)
I just tightened the alt plate and bracket to what I thought was sufficient? I couldn't find specifics on them.

Easy job, just a little time consuming because you need to remove the alternator and bracket.

bme30 · « **Reply #4 on:** November 13, 2012, 07:05:32 AM »

It looks like i have the same issue.. I thought it was the timing chain cover... But after seeing this thread i looked closer around the filter housing.. Yup, fresh oil build up.

Im going to tackle this repair this weekend. I'll post some pics

bmwman91 · « **Reply #5 on:** November 13, 2012, 12:17:55 PM »

Which side does it look to be dripping from?

deansweet · « **Reply #6 on:** November 13, 2012, 04:06:02 PM »

Drivers side. Right below the filter housing.
It tends to pool just above the upper oil pan. Right under the Alternator.

EricW · « **Reply #7 on:** November 13, 2012, 11:37:07 PM »

Yep, same. Drivers side, somewhere low on the block, at least below the filter housing. Thanks for the input so far guys. Seems ninety percent likely this is the problem. Can anyone confirm that profile gasket failure results in leaking oil, coolant, or both. I'd like to eliminate that possibility still.

deansweet · « **Reply #8 on:** November 14, 2012, 07:42:11 AM »

from what I have seen in a failing profile gasket it seems 99% of the time it's a coolant leak just above where the coolant pump is located. In this picture it's the square section of the gasket tends to get 'squished' to the point it stretches away from the head. Personally I would replace the oil filter housing gasket and see if it's still leaking as it is totally independent of the profile gasket. AS to replacing the profile gasket, I have read where it can be done without pulling the head but as I have done the head gasket twice now, I don't see how that could be possible but what do I know... Maybe another oil leak source is the timing chain cover gaskets/seal?

phoebus · « **Reply #9 on:** November 15, 2012, 08:43:02 AM »

Quote from: deansweet;117658

from what I have seen in a failing profile gasket it seems 99% of the time it's a coolant leak just above where the coolant pump is located. In this picture it's the square section of the gasket tends to get 'squished' to the point it stretches away from the head. Personally I would replace the oil filter housing gasket and see if it's still leaking as it is totally independent of the profile gasket. AS to replacing the profile gasket, I have read where it can be done without pulling the head but as I have done the head gasket twice now, I don't see how that could be possible but what do I know... Maybe another oil leak source is the timing chain cover gaskets/seal?

There is a way. There is a BMW special tool you can get or go to Home Depot and get a large taping knife which will serve the same purpose and cost you $7. When you are reinstalling the timing case, place the gasket on the case and then place the knife on top of it. Make sure to lube the knife so that once the case is in place you can easily remove the knife.

phoebus · « **Reply #10 on:** November 15, 2012, 08:44:13 AM »

http://www.homedepot.com/h_d1/N-5yc1v/R-202592294/h_d2/ProductDisplay?catalogId=10053&langId=-1&keyword=husky+taping+knife&storeId=10051#.UKT-a4GOeUQ

alim_h · « **Reply #11 on:** November 15, 2012, 11:05:59 AM »

Or you can use a piece of sheet metal if you have that lying around.

EricW · « **Reply #12 on:** November 16, 2012, 09:59:28 PM »

Just changed the filter housing gasket and o-ring. When it was apart it was clear to me that oil was leaking from the area. The o-ring in particular was really tired looking; dry. Ran the car for ten minutes with fresh cardboard beneath, and it has a few droplets but I think they're residual from the work that was done. No coolant drops at all, so hopefully I avoided the profile gasket red herring and got it licked.

I'd say based on the dozens and dozens of posts I read about M42 oil leaks that replacement of the the oil filter housing gasket and o-ring, which took 2-3 hours and cost $11, should always be the first step. Again, based on the reading, I'd bet this is the cause 90% or more of the time.

Thanks for the input guys!!

deansweet · « **Reply #13 on:** November 17, 2012, 07:05:18 AM »

Quote from: EricW;117730

I'd bet this is the cause 90% or more of the time.

Agree with you on that and it's such an easy task to complete.
I'd give it a 3.5 out of 10, with 10 being near impossible. Like I said in earlier post, It's just time consuming.

The o-ring on one of mine was so rotted it crumbled as I was attempting to peel it off.

Oh! and I found the part number of the BMW Tool Phoebus mentioned earlier as well.
http://tis.spaghetticoder.org/s/view.pl?1/06/41/38