Jaybird123

As I am finally in possession of new brake calipers/hoses/pads and LCA kit, I started work today on my '14 E550 coupe (Yes, C207 but no action on post in Coupe forum!). In dropping the covers underneath, I found two surprises of the not great kind. There isn't a ton of oil leakage yet, however I aim to resolve while the car is up on stands if possible. Would anyone care to offer any suggestions on source of issue(s) based on these photos attached? Not in a hurry, and ready to take more pics or explore based on suggestions...

Thanks!!



Pass side concern

Driver side concern

S-Prihadi

Almost can be guaranteed 99% that the VVT window is one of the oil leak source. Your engine M278 ?
https://mbworld.org/forums/e-class-w...lant-work.html

Jaybird123

oh thank you so much! Followed the link, watched the youtube video and learned so much! I will go investigate further around that plate now! Yes I have m278 btw, with ~108k miles

Jaybird123

Took some more pics, perhaps you can review and share more thoughts/suggestions if you have the time?

Right side engine, does appear some leakage from bottom and side towards center of car


Left side engine, not significant leakage I can see?

I see some buildup (circled) but do not know the part associated...?

So...still wondering about this left side leak that appears wet and some volume

Also wondering if the buildup here could all be from VVT plate, or another contributor as well...

S. Madman

Clean that engine, it should give a better idea of where the leak is coming from. I already posted how to clean the M278.

ChrisHimself

Check the underside of the oil cooler for function of the gasket/oil housing gasket. You have to remove the belt and thermostat to get to it so make sure you get a new thermostat gasket, I like the Mahle ones for feel. Pull the forward splash guard off, look up through the power steering pump area and you should see the underside of the oil cooler if theres any moisture there. I see this pretty often. Don't do anything until you actually confirm the location.

Every M273 has developed that leak BEFORE anything else. As for the leak in the first picture it's literally just the oil cap gasket letting go. The engines run hot so it makes sense. BMWs eat through oil cap gaskets like you wouldn't believe. I'm not an M278 expert but everything looks like it's exactly in the same place except for the obvious heat exchanger.

The engines also leak at the back around this age, from the PCV. Cam magnets/sensors too but it's rather small when it starts.