Common oil leaks on the s50/s52 engine?

[m3f_BigmansM]

Hello all,

I have had a pretty good experience with my s52 engine in terms of maintenance. I've had to do the usual things like vanos, coolant items, all the stuff u see repeatedly posted everyday.

My question is: Are there any common leaks on these engines? I'm trying to hunt down a very very minor oil leak and I just can't find it.

I think that the Charcoal canister might be one of these common oil leaks, but I think it's so minor that most people probably over look it.

Another would be the valve cover gasket, but I personally have already changed this.

Maybe the vanos gasket but, again I have already changed this and this is an easy one to visually see a leak.

[m3f_av2]

Check power steering hoses...very common.

[m3f_BigmansM]

Check power steering hoses...very common.

At the res or at the pump?

I actually think these might be leaking a lttle too!

[m3f_Oogie_M]

The power steering hoses usually start getting coated in gunk and it's hard to tell where the leak started.

[m3f_fiveightandten]

At the res or at the pump?

I actually think these might be leaking a lttle too!

They leak at the reservoir. ALL of them. You can replace the lines, and they'll be leaking again in 6 months. The car uses ATF for PS fluid. You can't reliably keep it sealed with a rubber hose slipped over a plastic coupler with a clamp around it. They leak by design.


I wouldn't say the motor has any *common* leaks (if I *had* to pick any it would be the VANOS and valve cover gaskets you mentioned).


But who cares, you have the car in front of you. If you see oil, clean it up and pay close attention to where it's coming from.


Where are you seeing oil?

[m3f_BigmansM]

They leak at the reservoir. ALL of them. You can replace the lines, and they'll be leaking again in 6 months. The car uses ATF for PS fluid. You can't reliably keep it sealed with a rubber hose slipped over a plastic coupler with a clamp around it. They leak by design.



I wouldn't say the motor has any *common* leaks (if I *had* to pick any it would be the VANOS and valve cover gaskets you mentioned).



But who cares, you have the car in front of you. If you see oil, clean it up and pay close attention to where it's coming from.



Where are you seeing oil?

I agree with you on the vanos and valve cover gaskets. I have seen several cars with these leaks. I wish you wouldn't have said "They leak by design" for the power steering hoses. Cause you know that it's true. BMW wouldn't have something intentionally leak



I can't find where my leak is coming from. I have scrubbed the engine before then started the chase and still had no lucks. It's obviously not a bad leak.

My brake fluid does NOT need to be topped off. My engine oil doesn't need to be topped off.



I honestly haven't check my atf fluid in a long time, so Ill do that. But, I doubt that's the cause.



With this thread I was hoping to establish a nice FAQ type thread for info.

[m3f_bigneil]

PCV valve and intake seals (i.e. during M50 swap) are worth replacing.

[m3f_BigmansM]

PCV valve and intake seals (i.e. during M50 swap) are worth replacing.

Which one is the PCV Valve?

[m3f_BigmansM]

The power steering hoses usually start getting coated in gunk and it's hard to tell where the leak started.

Mine hard lines get coated with gunk, but is this a leak? if so from where?. Here is a picture of the lines I am referring to:





But you guys seem to be talking about these:



Are you referring to 1 or 8 or both?



I know "fiveightandten" said they are leaking at the Res. I'm just trying to determine is there is a better solution to fixing these

[m3f_Oogie_M]

For me, #1 and #8 were both coated in gunk near the reservoir at 76k miles. I replaced both lines and the reservoir 2 years ago, okay so far.