You are joking right?

 

Sorry to tell you but the N52 was the best in-line 6 engine BMW ever built this far. The only documented issues with the N52 dealing with oil is the Vanos solenoids, VC gaskets and filter housing gasket. I've worked on many B25 and B30 engines dealing with oil issues in multiple countries and never had one with a leaking valve. Are there some out there that does I'm pretty sure we are talking about a maximum 18 year old engine. We are looking at an engine that was first introduced in 04 but to say the engine had a problem with oil leaking past the seals is a bit of a stretch. There were 9 variations being used in over 40 models for 11 years.

So to answer your question, no I'm not joking. Some owners have no clue if the engine is leaking or how bad it's leaking because of the under carriage covers. I've seen some bad leaks over my time working on BMWs. Hell my M54 had one years ago before it was fixed. Pan gasket, filter gasket and valve cover was leaking at the same time. Didn't fix it until I had to start adding oil in between my 7k oil change interval.

 

"The only documented issues with the N52 dealing with oil is the Vanos solenoids, VC gaskets and filter housing gasket."
I have to say that until this issue popped up this has pretty much been my experience, and what I have gleaned talking to BMW mechanics and reading others' experiences as well.

 

Isn't half a quart every 2-3 k for that mileage very good performance, though? Even outstanding?

 

My N52 does that and I'm not even concerned. I already know it's coming from my oil pan gasket.

 

A new oil separator, and new valve cover and oil cooler / filter housing seals fixed my "real oil leaks". I know that there is still some, but I "fixed" that by parking an old shop towel on top of the plastic under-car shield. Now that tiny leak won't ever end up on my driveway or garage floor. Good as new! ;-)

 

I guess so but I don’t like oil consumption since I have zero oil leaks anywhere

 

So finally got around to flushing the engine and changing spark plugs. There does appear to be leaking on right side, as can see on underside of the belly cover. There was some minimal oil on a couple spark plug threads (I think 1 and 2) and then some actual oil pooling in cylinder 6, which seems odd). What do you make of the photos attached?

 

You are living dangerously. All that grease on the engine and all over the parts near the serpentine belt is trouble. If the belt comes off, it may well get shredded behind the crankshaft pulley and get pulled into the engine and then your engine is toast or mega-work to get back. More than likely you need a new oil filter housing gasket and oil cooler gasket. You also need to get all the crap off the front of the engine. And, get a new belt.

 

What twh said!

It's often hard to tell everywhere a BMW I6 is leaking because they can have so many leaks! The valve cover gasket is another likely candidate. The best thing to do (after you replace the oil filter / cooler housing gaskets and the serpentine belt) is to clean up the engine block as much as possible, and look for new, fresh oil leaks to see if you cured the entire problem (or not).