Oil leaking from front of engine?
 

I seem to recall reading about a common oil leak that shows up around the front of our engines.

I changed my oil yesterday (just over 100k miles now) and I noticed a fair bit of oil spray on the poly-v belt and below on the front belly pan. I couldn't seem to find the source, so I cleaned things up a bit and will keep an eye. It hasn't been enough to cause my oil level to drop, but I am concerned and want to keep on top of things.

Anybody have this problem or remember reading about it?

Oil leaks follow weird patterns. Best thing to do is give the engine a good clean up,especially around the area where you have the leak. After that check frequently and you will find it.
Plus you need to provide more details of the exact area where you see the leak. You know that if it's the driver side,it could also be power steering fluid that build up on the bottom cover.
Oil got on the belt coming from the top or bottom? If top,it's the oil cooler...you got 3 seals in there.
Bottom could be crankshaft seal but unlikely.
Most likely oil level sender by the oil pan if on the passenger side.
Like I said,it could be many places and also deceiving.
100K sounds about right for these if they haven't been done...

Seemed to be more on top/driver side. I am leaning towards the oil cooler, but I'll have to keep an eye for the next few weeks to know for sure.

Another common leak on the drivers side is from the PVC cover on top of the valve cover for lack of a better description. If you look at drivers side valve cover on top their is another cover, it is a baffle for the PVC and it likes to leak. Their is not a gasket for it according to my local dealer, use RTV silicone to seal it.

Dan

If I recall what you are talking about, that is at the back of the engine, not the front...right?

Starts right on the front of drivers side valve cover, oil filler cap screws into it and it travels the length of the cover IIRC

Dan

It's not his small cover Dan. I know you've just purchased your E55 and you will discover in time our cars secrets. Maybe not so soon for you with the mileage you're having... :)
The small cover does leak but not to the extent he's describing,where oil made it to the bottom and onto the protective shield.
Most likely,up there and onto his belt is the oil cooler. BTW,I would suggest to fix it soon,because in time that leak will damage your serpentine belt.
If indeed it turns out to be your oil cooler,I would suggest fixing it during the oil change,as the filter has to come out and there's a big seal under this large nut. BTW,do no tighten that nut too much after installation,torque it if possible. You'll also have to remove the cooler and split it open to change the 2 small seals inside. This part is going to get messy as you'll lose some coolant. :naughty:
I've fixed all leaks in my car,including the rear main seal,so I know where this baby's leaking. At 160K with no maintenance,I had to do them myself...pain in the butt,but I'm happy :zoom:
BTW Dan,I see you're in Bucks County PA...I drive there once in a while to see friends,maybe we'll meet one time so you can see how a Senior E55 looks like... :rolf:

Hi Neanicu888 I wasn't suggesting that it was his leak, only another area that leaks on that side. It is good to know about the oil cooler and will keep an eye on this in my car and will most likely change out those seals you mention as a preventative measure when the car gets close to 100,000 miles. Thanks for the heads up, good information to have for future reference.

Would be great to meet sometime, let me know when you are going to be in the area and if their is no salt on the roads I'll be glad to meet. Thanks again for the above.

Dan

No problem Dan,we don't know for sure it's the cooler either,we're just guessing here...

If you zoom in on my pic, you can see it is leaking front left, draining towards the drop hole. This is after wiping it down, driving mixed in town and highway, both conservative and spirited driving. I am sure it is getting on the belt as even the air intake has collected some oil on the underside. I have not been under it yet to pull the belly covers off. Not sure I would see the problem from there.

There is a fiber wrapped hose that is soaked pretty good in the picture. Not sure it has anything to do with the actual leak.
https://cimg8.ibsrv.net/gimg/www.mbw...179bc04e06.jpg


Oil leak

is it coming from your oil pressure test port? Mine was leaking in the same way and getting the belts and the undertray dirty. I changed #29 in this picture and sprayed down the front of the motor with degreaser, no more leaks.
https://cimg9.ibsrv.net/gimg/www.mbw...8df0ea8fd3.jpg

Thanks. I will take a closer look in that area.

I had a leak from this cover as well, found it had gasket maker behind it which wasn't doing the trick. New OEM gasket seems to have solved it.

Have you definitively ruled out the driver's side breather cover leaking? I had oil leaking in a similar location and it was coming out of a bad seal on the breather cover (which is the metal cover on top of the valve cover). To see check this simply remove the plastic air intakes and engine cover and closely examine your breather cover. I had oil dripping down the side of the breather cover (particularly more so after engine was hot - obviously). This is a highly common leak for these engines. In my case, the oil was leaking down the front of the engine leading me to think it was coming from the "oil pressure port"/"oil port test cover" which is on the front of the engine (read here: https://mbworld.org/forums/e-class-w...-oil-leak.html). If you have eliminated the breather covers and oil pressure port, then check the oil cooler (as others have said) and oil filler seals which also sometimes go, but a bit more rarely than that oil test port from my research when I was trying to pinpoint the leak that ended up being the breather covers. :zoom:

Thank you all, I will be checking the breather cover and Oil pressure check cover for leaks. Just PIA to really get a good look at either. Couple really good posts and pics over on benzworld for same issue.


:y

When I first bought my car the passenger side breather cover was leaking bad but it was just pooling between the valve cover and the intake. I have never seen the drivers side leak on either of my cars.

For the pressure port a mirror and small hands are helpful. The upper rad hose kinda gets in the way but you can do it without removing it or the fan shroud.

I believe it is coming from the oil cooler. After a little tightening I believe it has slowed. I hope to replace both seals in there at next service A, in about 2500-3000 miles.

If you zoom in past the belt is the oil cooler with a few small drips. This was after I tightened and cleaned everything. After wiping these off, overnight cool down, no new drops. Have some driving tonight so I will see if it's worse or better then it has been.

https://cimg1.ibsrv.net/gimg/www.mbw...648197b8ac.jpg

I believe with that little bit of tightening, it has stopped dripping, at least not enough to splatter the entire front of the engine. Thanks for all the help and advice.

It has been 2 months and 1500+ miles without a drop of oil since replacing the 3 gaskets. The originals were very hard and didn't flex.

I've already replaced the pressure port gasket, and it fixed on leak, but I've got another that seems to come off the upper rear of the engine somewhere. I'll take a good look at my breather covers and valve covers, I'd love to get it all sealed up and leak free. Thanks for the info!

Bolt slipped
 

so i changed that seal and when i was tightening one of the bolts the bolt slipped and wont tighten anymore, whats the best solution

you could try to re-tap the threads in the whole of you have the tools or can borrow them. If that is not possible, maybe a smidge larger tap, but have the correct bolt to go in to match the new size.

if that doesn't work, replace the unit.

I had a similar leak that we traced down to the oil cooler. After some research determined that it was likely a seal that goes between the cooler and one of the hoses. Ended up replacing the whole cooler along with the seal just for assurance. No oil leaks since.

I have a leek at the front also
 

hi, can anybody tell me if my leek is serious, attached is where the leek is dripping from, I don’t know too much about engines so any info would be much appreciated, see pics att
https://cimg9.ibsrv.net/gimg/www.mbw...94e8ab758f.png
https://cimg0.ibsrv.net/gimg/www.mbw...e3be91a966.png
ached