[vbfronkis]

Hi all-

Just got my e90 last week and my Bentley manual has arrived. Time to tear into it!

PO (original owner) was pretty meticulous about maintenance so the car's in great shape. It's now got 108k miles and I think it's time for a few oil gaskets. Here's what I mean:

Oil Filter Housing:

Valve cover:

It isn't dripping oil so that's good, but it's definitely a leak. (Though no warning about oil level either.)

I'm diagnosing it as oil filter housing gasket and valve cover gasket. Given the mileage, I'm going to do the whole valve cover as well.

Do you guys agree?

[David0ff]

Agree, fun little project.
Also check the oil pan, you may be unpleasantly surprised.
Although its more of a mission to change that gasket, it is very doable at home with an engine support bar.

Good Luck

[Love The Drive]

Originally Posted by David0ff

Agree, fun little project.
Also check the oil pan, you may be unpleasantly surprised.
Although its more of a mission to change that gasket, it is very doable at home with an engine support bar.

Good Luck

Thank you for posting. I have a similar situation, though it looks like I shouldn't be complaining when compared to your leak. I thought mine was bad. Car has 115,000 miles on it.

So, oil filter housing gasket, valve cover gasket, and oil pan you say?

My mechanic has actually said nothing about the leak. It's too small to be a problem I guess? I do fill a quart of oil every 2-3 months though. I drive about 1,200 miles per month. (The need to fill oil may be due to burning oil though, not from a leak).

[David0ff]

The problem with the oil housing gasket leak is not so much external, it is rather internal.
Due to the oil / water channels being in close proximity you get a mix of water in the oil and oil in the water. That is really the main concern and one of the primary reasons for which this OHG should be a preventive maintenance point like the accessory belt.

In both cases above there is evidence of a valve cover gasket and an oil housing gasket which need replacement.

Chances are, with those 2 weeping, the oil pan gasket need attention as well.

[roundle]

While you're in there, make sure your (external) head bolts are still intact.

After cleaning my engine so that I could diagnose a (sudden) oil leak, turned out one of my external head-bolts jettisoned its head which allowed quite a lot of oil to leak up through the helix.

Here's a pic of the bolt I am referring to:

http://www.pelicanparts.com/BMW/tech...mall/pic01.jpg

[ZeroSum]

While you are in there check the ESS as well.

[vbfronkis]

Originally Posted by ZeroSum

While you are in there check the ESS as well.

ESS? Not up on my N52 TLAs

[matteblue3er]

Originally Posted by David0ff

The problem with the oil housing gasket leak is not so much external, it is rather internal.
Due to the oil / water channels being in close proximity you get a mix of water in the oil and oil in the water. That is really the main concern and one of the primary reasons for which this OHG should be a preventive maintenance point like the accessory belt.

In both cases above there is evidence of a valve cover gasket and an oil housing gasket which need replacement.

Chances are, with those 2 weeping, the oil pan gasket need attention as well.

A leaking oil filter housing gasket is a problem however it leaks, whether internal or external.

If oil drips onto the belt, it can cause it to slip and potentially get wrapped around the crank pulley. If you run the engine long enough, the belt will get pulled into the motor, destroying the front crank seal and get shredded up in the timing chain system which will throw bits of belt through out the motor.

+1 for checking the ESS or eccentric shaft sensor. If there is oil in the connector, the sensor needs replacement. The backing plate on the sensor will fail and allow oil to get into the sensor. This will cause the sensor to intermittently read incorrectly due to added capacitance from the oil.

[ZeroSum]

Originally Posted by vbfronkis

ESS? Not up on my N52 TLAs

Eccentric Shaft Sensor

http://www.e90post.com/forums/showthread.php?t=697252

[vbfronkis]

Originally Posted by ZeroSum

Eccentric Shaft Sensor

http://www.e90post.com/forums/showthread.php?t=697252

Ah right. Saw that in a valve cover gasket YouTube video. Figure I'd do it while I was in there.