Mercedes-Benz Forum banner

om642 bluetec Oil Leak, Please help identify

39K views 17 replies 10 participants last post by  AIDROOS  
#1 ·
Hi, I have a 2011 E350 Bluetec. Noticed oil leak after I park the car, just a few drops. Took it to a dealer and mechanic. They said it might be an oil cooler leak but could not confirm without opening the engine.
After opening the hood, i can see some deposits on the turbo intake. Could this cause the oil leak? Please see photos, any expert advice is appreciated.
or is this om642 turbo inlet seal leak?

Thank you
 

Attachments

#2 ·
that's a pretty common build up. -- to help it from building up, do not over fill the engine. keep it 1/2 b/t min and max.


easy way to tell if cooler is to look at the drain hole on drivers side of block by the bell housing. this is done with veh on a lift. if its running out that hole, than you need an oil cooler.
 
#4 ·
Vortecpwr, Do you know if the 2011 Bluetecs come with the new purple oil cooler seals or the older orange seals? What are the other possible oil leak points for the 2011 Bluetec? Mine is at 80K. What other issues should i look forward to? The car is driven 100 mi each work day, mostly highway, but stop and go traffic
 
#3 ·
My intake looked the same on my 2008 E320BT with 56,000 miles. Unfortunately it had leaking oil cooler seals.On the good side MBUSA picked up the repair costs. If your car has a good service history, they may help you out.
 
#5 ·
as far as seal I could not tell you. I did a 14 about a year ago now and it had the orange seals not the purple seals. SOOOOOO, it could have either. they both leak, IMO its a bad design. But you will see oil leak on the ground, not up top.

oil cooler being the big issue.
I have heard of some replacing front crank seals due to leakage.
the 642 diesel also has a timing chain stretch issue. I have not seen this yet, only heard about it in MB training.
 
#17 ·
642 Chain Stretch

the 642 diesel also has a timing chain stretch issue. I have not seen this yet, only heard about it in MB training.
This is real! I was in the process of buying a 08 GL320 CDI and backed out, the chain slap was awful and it only had about 95K turns on the meter. Didn't think it was a problem for the 642, but obviously it is a problem!
 
  • Like
Reactions: AIDROOS
#6 ·
I have a 2011 E350 bluetec and just experienced this myself. I'm betting it's the same exact thing with your car...the oil cooler. Sounds like an easy fix but they have to remove most of the engine to get to and replace the oil cooler. I ended up getting it done for $1500. No oil leak anymore...but they did mess something up. It sounds like I have a turbo leak now. I haven't taken it back in yet for that.
 
#10 ·
Hi, I guess I am another victim of the notorious OM642 oil cooler leaking... Did you have it fixed with $1500 at dealership? what do you mean by turbo leak? I was totally upset by this car... the problem happens after I have the oil changed, and it seem that I have put too much oil in it(8.5 quarts), I guess the pan still holds some residual oil that makes the 8.5 quarts too much... My another issue with this car was a check engine light with code p2413, which is related to exhaust system, it pop out right after I refilled the DEF.... This car made me sad as it always turn out something bad when I do something good to it....
 
#7 ·
I would start with replacing the turbo intake seal (big orange seal inside the black pipe) as well as the crankcase breather pipe seal, $30 in parts tops. Then clean the intake valley with degreaser thoroughly and flush with water.

My 2008 was diagnosed with a bad rear main seal 5 years ago, it was just the crankcase breather and turbo intake seal which I have resealed twice now, I goop it up with perma seal gasket sealer and a new seal each time. Never touched the oil cooler to date which the dealer always claims is at fault, but I have never had to add oil, just a drop visible on the bottom of the bellhousing at times. I do smell it burning off the exhaust on a good hill climb...

I am under the impression there is so much stigma attached to the oil cooler leaking that it is done regardless of the source of the leak, and since the turbo pipes are part of the job anyways it ends up being fixed. Yes, severe leaks are usually the oil cooler, but minor ones tend not to be. I have a nice flexible LED light I shine down into the intake valley to look around when changing the fuel filter, you can get a good look around (not all the way to the oil cooler but enough to see if there is oil pooling down there). These engines do have a good amount of crankcase blowby which if leaking can really drip a lot.
 
#9 ·
Hi, my 2011 E350 bluetec is experiencing the exact same thing as you described here. I see the same oil sludge buildup at the turbo inlet. But the oil leaking is too everyday, I SUSPECT it's from the oil cooler seal. Have you had the issue fixed? what exactly is the problem and how much did you get it fixed? Thanks so much!
 
#16 ·
It is a Federal Warranty that trumps any state requirement. They said it wasn't part of emissions and covered so I told them to take it off. They said they couldn't do that because it was part of the emission system. As I said you will have to work on them but it clearly is part of the emission system.