Follow-up on my M50 oil leak & coolant leak

[Dick Schneiders]

My European car independent mechanic/friend had some free time this afternoon and space in his shop to get my 1991 525i up on his lift. We both looked for quite a long time and were still not able to determine where my M50 engine is leaking. In fact, the coolant leak didn't happen at all. We checked the hose connection at the back of the cylinder head and everywhere else we could think of and there was no coolant leak or any residue that would help us to find the source.

The oil leak, however, was there but we were not able to find where it was leaking. The engine is quite dirty and has a lot of oil residue so he suggested that I clean the engine and drive it so that we might be able to tell better where it is leaking. With me not having a garage to work in, I am going to have to wait for warmer weather - hopefully this weekend.

He is almost positive it is *not* a head gasket, fortunately, and he checked for a leak around the valve gasket I replaced and didn't think it was there. He also thinks that the oil leak is actually at the front of the engine and not the back where I found it dripping.

Are some of the most likely places, for an oil leak, the timing chain cover and the oil filter housing where it connects to the engine? Where else towards the front of the engine would be a possibility, excluding the head and valve gaskets?

Thanks,

Dick Schneiders

[granit_silber]

My European car independent mechanic/friend had some free time this afternoon and space in his shop to get my 1991 525i up on his lift. We both looked for quite a long time and were still not able to determine where my M50 engine is leaking. In fact, the coolant leak didn't happen at all. We checked the hose connection at the back of the cylinder head and everywhere else we could think of and there was no coolant leak or any residue that would help us to find the source.

The oil leak, however, was there but we were not able to find where it was leaking. The engine is quite dirty and has a lot of oil residue so he suggested that I clean the engine and drive it so that we might be able to tell better where it is leaking. With me not having a garage to work in, I am going to have to wait for warmer weather - hopefully this weekend.

He is almost positive it is *not* a head gasket, fortunately, and he checked for a leak around the valve gasket I replaced and didn't think it was there. He also thinks that the oil leak is actually at the front of the engine and not the back where I found it dripping.

Are some of the most likely places, for an oil leak, the timing chain cover and the oil filter housing where it connects to the engine? Where else towards the front of the engine would be a possibility, excluding the head and valve gaskets?

Thanks,

Dick Schneiders

dick,

my 92 525 has a small mysterious oil leak as well. My indy couldn't find last time I was in. The other day I replaced my foglamp bulbs and spotted dropplets forming from where (I assume) the oil drain plug is. This explains why the indy couldn't find it. I don't know how large your leak is, but check there.
-ashley

[Interceptor]

my 92 525 has a small mysterious oil leak as well. My indy couldn't find last time I was in. The other day I replaced my foglamp bulbs and spotted dropplets forming from where (I assume) the oil drain plug is. This explains why the indy couldn't find it. I don't know how large your leak is, but check there.

I have the same problem with my '92 525i. It looks like the oil is leaking where the oil level sensor is - at least that's what my mechanic told me. I do not have any coolant leaks but the coolant level sensor really annoys me! It seams to lose contact every now and then without apparent reason. Maybe it's the oxidation or dirt/residue since it gets splashed when I drive over puddles.

Regards

[winfred]

most common m50 oil leak is the oil filter housing to block seal

[DanDombrowski]

Not to try to make you even more confused, but power steering fluid, when mixed with all the dirt and grease on the block, can look alot like motor oil. Mine leaks down onto the oil pan and drips off of that, so it very much looks like the oil pan has a leak.

[alex 1993 525i auto]

Hi all!

I'm searching the posts since a while to get info on oil leak from oil filter housing. After reading everything I could find on this topic here is my first post (or thread reply).

I have a 1993 (build 05) 525i auto M50TU with 1.5 year old valve cover gasket, oil pan gasket, rear plate seal. I still have a moderate oil leak (1 quart every 500-1000 miles) from oil filter housing.

My mechanic told me it's gonna be 500$ for the parts and 3 hours of work. He said there are no gaskets to change, I got to have a new housing.

Any clue if I could get that done for cheaper than 900$? Is it true that it is not serviceable on my car? (remove, clean, change gaskets, o-rings, etc?)

If it has to be replaced as a whole, is there other stuff I should ask to have a look or replace once in there?

I did some basic work myself on the car before (like replacing heater valve, aux. water pump, ac microfilter, headlight assembly, Gearshift/neutral safety switch, Front left door bowden cable for opening door and window motor) but I'm not sure if I could replace the oil filter housing myself... (I also need to remove steering pump?)

There is no info in my Bentley how to do this oil filter housing replacement, someone has a procedure? (with pics it would be better of course but anyhow...)

Thanks for any advice!

Alex

Also, huge thanks to people posting solutions, not only questions! I've been using this site since 2 years I got my first Beemer and it helped a lot!

[ryan roopnarine]

search for m50 oil canister gasket in the search. the leak is caused by two small, less than $15-20 (non-dealer price) gaskets inside the housing. you have to take off the belt, fan clutch and shroud, alternator, and power steering pump to get inside, but it is an all labor issue to deal with. the housing is likely not defective unless there is an obvious crack somewhere.

[repenttokyo]

it's most likely your coolant is only leaking while the car is running and under load.