Oil Leak Persists!

[FL318is]

Ok bimmer heads, riddle me this.

I have changed the upper pan, lower pan and filter housing gasket and
o-ring.  Torque to fac specs, prepped the threads and gaskets.

I still have a leak :eek: :confused:

The leak looks as though it is coming from the oil filter housing.  Is there another gasket or area I need to check?  Not looking forward to replacing again but will do it.  Hopefully you guys have insight and experience.

[Febi Guibo]

hey man... to expedite things a bit, can you take a picture, from the top of the engine bay, and then from the bottom, if you can, showing the leak?

off the top of my head, it's probably something simple... if it's a little bit of oil, check the sender plug (eg, it's letting oil run down to the housing).

[FL318is]

I will take pics tonight.  Thanks again!

[M42boy]

I will take pics tonight.  Thanks again!

No, there is only the flat gasket material and then the rubber O-ring.  I did mine recently.  But, I had to use a little plastic scrubbing wheel to get all the old material off...   Did you clean the surface really good before re-installing with the new gasket??  

Febi has a point... did you replace the oil pressure sensor at the back of the housing?  If so, check there first, but don't over-torque it either.  

I've learned that it's REALLY hard to tell where leaks from the front of the motor are coming from as the fan blows it around so much.  It could be coming from someplace entirely different as well...  the front timing case covers on these cars leaked almost from day 1.  

If you don't see anything obvious, start looking around the front timing cases or back behind the crank pulley.

[FL318is]

Did you clean the surface really good before re-installing with the new gasket??  

I thought I did!

Febi has a point... did you replace the oil pressure sensor at the back of the housing?  If so, check there first, but don't over-torque it either.  

Did not replace it.  Should I?

I've learned that it's REALLY hard to tell where leaks from the front of the motor are coming from as the fan blows it around so much.  It could be coming from someplace entirely different as well...  the front timing case covers on these cars leaked almost from day 1.  

That area is very dry.


...the front timing cases or back behind the crank pulley

Thanks, I will give it another look!


Guys I really appreciatte the help.

[FL318is]

I just read Febi great adventure, pg 1.  Could my oil leak be a crankshaft seal?  I took some pics and will edit and post them for a better look.

[FL318is]

I don't know if this helps.  I can take more.

Pic 1  The oil visible collects on the side and top of the manifold just behind and below the oil filter housing.

Pic 2  You can see oil running down the lower oil pan but the pan gasket doesn't appear to be the problem.

My oil loss is minimum per the dipstick.  There is probably area amount the size of six randomly placed quarters.

Going to continue driving it daily unless you guys tell me to stop.

[FL318is]

This is what the underside looked like before.

[dino245]

You may want to get a mirror on some kind of extendable stick and look under the intake manifold. This is just and idea but it may be coming out of the head gasket at the point were the oil transitions from the block to the head. The gasket may have a rubber ring in the head gasket to seal this off and over time the rubber has gotten hard and no longer seal. One other thin I have seen is the oil pressure switches will fail internaly and the rubber diagram that seperates the electrical part of the switch and the oil will fail and oil will come out of the electrical connector.

Just some ideas of what I have seen in the past.

[FL318is]

You may want to get a mirror on some kind of extendable stick and look under the intake manifold. This is just and idea but it may be coming out of the head gasket at the point were the oil transitions from the block to the head. The gasket may have a rubber ring in the head gasket to seal this off and over time the rubber has gotten hard and no longer seal. One other thin I have seen is the oil pressure switches will fail internaly and the rubber diagram that seperates the electrical part of the switch and the oil will fail and oil will come out of the electrical connector.

Just some ideas of what I have seen in the past.

Thanks!  I will take all any and all suggestions.

[BrandC]

Have you thought about using UV dye oil-leak detector? This is what some mechanics use before an oil change.

You can go onto Autobarn.com and find this additive that you pour into your oil, run the car for a few hours, then grab a black light and find where the leaks are by the shining green spots.

[FL318is]

Cool idea.  I will check with him today.  Is it possible my block has a crack?  The oil leak increases as the engine warms up.

This is a lighter pic of where the oil seems to collect.  Right behind the oil filter housing.  We checked the sensor and it is tight.  There is oil present in the sensor connection.

[dbgrubbs]

What is the sensor made from? I once had a car with a mysterious oil leak. Turned out that the bakelite material was cracked and the oil was actually coming out of the sensor. Check it out.

[FL318is]

The material appears to be a bakelite material.  We pulled it off last night and did not notice a crack but the mosquitos were biting the h#^^ out of us so we could have overlooked it.

[dbgrubbs]

Take it off and pressure test it. Maybe the seal in it is gone. Worth a look anyway.