Diesel Forum Forum for Diesel engine vehicle related discussion
Sponsored by:
Sponsored by:

OM642: New viton oil cooler seals still leaking...or?

Thread Tools
 
Search this Thread
 
Rate Thread
 
Old Jun 30, 2019 | 01:40 PM
  #1  
Diesel-King's Avatar
Thread Starter
Junior Member
 
Joined: Aug 2012
Posts: 17
Likes: 0
R 320 CDI
OM642: New viton oil cooler seals still leaking...or?

Hi,
One year ago the MB dealer changed the oil cooler seals to the new purple viton ones, replacing the old orange seals on my R320 cdi.

Unfortunately oil has started leaking again through the lower left engine weep hole.
There is no oil dripping from the turbo air inlet so I am inclined to think the problem is again with the oil cooler seals.

But I have also read that the turbo also has an oil feed (through the turbo pedestal?)
How can I tell if it is the turbo oil feed seals without removing the turbo?

Thanks for your help.
Reply
Old Jun 30, 2019 | 05:40 PM
  #2  
kajtek1's Avatar
MBWorld Fanatic!
15 Year Member
Photogenic
Liked
Loved
 
Joined: Jan 2009
Posts: 9,224
Likes: 1,798
From: V E G A S
1922 Ford Model T / no OBD
Those engines also have weaker seals on oil filter housing.
With complexity of the engine, you might want to spend 10 bucks on snake camera that attaches to your android.
Reply
Old Jul 1, 2019 | 03:20 AM
  #3  
Diesel-King's Avatar
Thread Starter
Junior Member
 
Joined: Aug 2012
Posts: 17
Likes: 0
R 320 CDI
Originally Posted by kajtek1
Those engines also have weaker seals on oil filter housing.
With complexity of the engine, you might want to spend 10 bucks on snake camera that attaches to your android.
Thanks for the tip but it's not leaking from the oil filter housing (front of the engine).

Has anyone had leak problems with the viton oil cooler seals?
Reply
Old Jul 11, 2019 | 01:32 PM
  #4  
Luke.Berger's Avatar
Newbie
 
Joined: Jul 2019
Posts: 5
Likes: 0
Mercedes C320CDI
Hi, i have same problem...did you fix it ?

Thanks for your help.
Reply
Old Jul 13, 2019 | 05:28 AM
  #5  
peter2772000's Avatar
MBWorld Fanatic!
5 Year Member
Liked
Loved
Community Favorite
 
Joined: May 2017
Posts: 1,234
Likes: 155
From: Montreal/Cape Coral FL
2012 X6 35i Sport, 2013 ML 350 BT, 2019 4Runner TRD Pro, 2020 CRV-AWD
The newer purple seals handle the heat better, but are harder and don't seal as well. Heat is your enemy here.
If the seals are leaking, replace them and lose the belly pan and engine cover in order to mitigate under-hood temps.
Reply
Old Jul 15, 2019 | 03:30 AM
  #6  
kajtek1's Avatar
MBWorld Fanatic!
15 Year Member
Photogenic
Liked
Loved
 
Joined: Jan 2009
Posts: 9,224
Likes: 1,798
From: V E G A S
1922 Ford Model T / no OBD
I sold my 2008 car with OM642 engine, but I used it in 120F heat, while monitoring temperature on climatronic and most of the time it would stay at 80C, while dropping to 78C going downhill. Electric fan would go to high when I park the car with AC on.
Bare in mind, that MY had no DEF, but at 180k miles was not new neither.
Reply
Old Jul 15, 2019 | 11:42 AM
  #7  
Towmater's Avatar
Member
 
Joined: Mar 2019
Posts: 145
Likes: 14
Ml350 bluetec
If you get a blanket you can lay on top of the engine and look straight down the center of the turbo from the top. You'll see the two torx bolts holding the turbo and if you shine a light beside them that will show you if its leaking from the pedestal.
Reply
Old Jul 17, 2019 | 10:44 AM
  #8  
Diesel-King's Avatar
Thread Starter
Junior Member
 
Joined: Aug 2012
Posts: 17
Likes: 0
R 320 CDI
Originally Posted by Luke.Berger
Hi, i have same problem...did you fix it ?

Thanks for your help.
No, I still gave the leak although I changed to the purple seals.

Will try to see looking over the turbo if it leaks by the pedestal...will report back....
Reply
MB World Stories

The Best of Mercedes & AMG

story-0

6 Mercedes Models That Did NOT Age Well (But Are Somehow Still Cool)

 Verdad Gallardo
story-1

Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun

 Verdad Gallardo
story-2

Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren

 Verdad Gallardo
story-3

8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine

 Verdad Gallardo
story-4

Flawlessly Restored Mercedes 190E Evo II Heads to Auction

 Verdad Gallardo
story-5

Electric Mercedes C-Class Unveiled: 11 Things You Need to Know

 Verdad Gallardo
story-6

Mercedes EQS Gets A Major Update: Everything You Need to Know

 Verdad Gallardo
story-7

5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve

 Verdad Gallardo
story-8

Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping

 Verdad Gallardo
story-9

10 Most Reliable Mercedes-Benz Models You Can Buy Used

 Verdad Gallardo
Old Jul 18, 2019 | 04:56 PM
  #9  
Luke.Berger's Avatar
Newbie
 
Joined: Jul 2019
Posts: 5
Likes: 0
Mercedes C320CDI
Okay. Thanks
Reply
Old Jul 18, 2019 | 04:57 PM
  #10  
Luke.Berger's Avatar
Newbie
 
Joined: Jul 2019
Posts: 5
Likes: 0
Mercedes C320CDI
Originally Posted by Diesel-King
No, I still gave the leak although I changed to the purple seals.

Will try to see looking over the turbo if it leaks by the pedestal...will report back....

Okay. Thanks
Reply
Old Jul 29, 2019 | 03:33 PM
  #11  
Luke.Berger's Avatar
Newbie
 
Joined: Jul 2019
Posts: 5
Likes: 0
Mercedes C320CDI
Originally Posted by Diesel-King
No, I still gave the leak although I changed to the purple seals.

Will try to see looking over the turbo if it leaks by the pedestal...will report back....

So did you find a problem?
Reply
Old Jul 30, 2019 | 10:47 AM
  #12  
Diesel-King's Avatar
Thread Starter
Junior Member
 
Joined: Aug 2012
Posts: 17
Likes: 0
R 320 CDI
I used an android endoscope camera but could only notice that there is no oil around the front part of the oil cooler (front of engine).....could not see if the rear end of oil cooler had any spilled oil.

I guess I will not advance unless I start removing parts standing in the way....but I'm too lazy for that.

As I see it, oil is still leaking through the new viton oil cooler seals or the turbo pedestal oil seal....can not think of any other cause.
Reply
Old Jul 30, 2019 | 04:45 PM
  #13  
Towmater's Avatar
Member
 
Joined: Mar 2019
Posts: 145
Likes: 14
Ml350 bluetec
Originally Posted by Diesel-King
I used an android endoscope camera but could only notice that there is no oil around the front part of the oil cooler (front of engine).....could not see if the rear end of oil cooler had any spilled oil.

I guess I will not advance unless I start removing parts standing in the way....but I'm too lazy for that.

As I see it, oil is still leaking through the new viton oil cooler seals or the turbo pedestal oil seal....can not think of any other cause.
So, did you look down by the torx and look at the pedestal?
Reply
Old Jul 30, 2019 | 04:45 PM
  #14  
Towmater's Avatar
Member
 
Joined: Mar 2019
Posts: 145
Likes: 14
Ml350 bluetec
You can also put in some dye.
Reply
Old Jul 31, 2019 | 03:39 PM
  #15  
Diesel-King's Avatar
Thread Starter
Junior Member
 
Joined: Aug 2012
Posts: 17
Likes: 0
R 320 CDI
No, not possible unless I remove the air intake and possibly other parts like the fuel filter....will do it when the car is serviced.

Yes will add some dye once I receive it from Ebay.

Last edited by Diesel-King; Aug 2, 2019 at 07:39 AM.
Reply
Old Aug 8, 2019 | 01:54 PM
  #16  
Luke.Berger's Avatar
Newbie
 
Joined: Jul 2019
Posts: 5
Likes: 0
Mercedes C320CDI
Originally Posted by Diesel-King
No, not possible unless I remove the air intake and possibly other parts like the fuel filter....will do it when the car is serviced.

Yes will add some dye once I receive it from Ebay.
Did you find a problem or no ?
Reply
Old Sep 26, 2019 | 10:22 AM
  #17  
dhurley's Avatar
Member
 
Joined: Dec 2018
Posts: 247
Likes: 59
From: Lawrence, Kansas
GL320
722.9 bushing style front pumps often fail and will weep fluid through the bell housing and mimmick the oil cooler seal leak.
Reply
Old Sep 26, 2019 | 12:09 PM
  #18  
Diesel-King's Avatar
Thread Starter
Junior Member
 
Joined: Aug 2012
Posts: 17
Likes: 0
R 320 CDI
Took of the bellhousing rubber plug and cleaned up all oil....glued a piece of rectangular rubber underneath the bell housing hole with some strong silicone to determine if the oil spill came from inside the bell housing and left the hole open......but no, the spill does not come from inside the bellhousing!! The spill must come from the left side weep hole...but I'm not 100% sure...still investigating...
Reply
Old Oct 4, 2019 | 05:51 PM
  #19  
houseofdiesel's Avatar
Member
 
Joined: Dec 2011
Posts: 144
Likes: 10
2008 R320 CDI, 2006 smart fortwo cabrio, 1983 240D, 1982 300SD, 1980 300SD
Did the oil cooler get replaced at the time of the seals? They are known to warp and leak, not just the orings fail.
Reply
Old Jul 5, 2021 | 05:19 AM
  #20  
Mohammad C's Avatar
Newbie
 
Joined: Jul 2021
Posts: 2
Likes: 0
2013 mercedes s350 bluetec
New purple oil cooler seals leaked again

Originally Posted by Diesel-King
Thanks for the tip but it's not leaking from the oil filter housing (front of the engine).

Has anyone had leak problems with the viton oil cooler seals?
I have had this happen to me on my 2013 S350 bluetec. The first time I used all original Mercedes parts and then about 5000 miles later the oil leak developed again so now I’m thinking that the oil cooler itself has a warped so I am going to replace the seals again along with a new oil cooler. there’s simply too much heat where the oil cooler is located and therefore it it it just doesn’t last. Best to change out the oil cooler the first time.
Reply
Old Jul 5, 2021 | 11:21 AM
  #21  
GoodByeHonda's Avatar
Senior Member
 
Joined: Jan 2013
Posts: 305
Likes: 42
W211 E320 Diesel OM642
Can you please do us a favor and check the oil cooler with straight edge when you remove it?
imo it is more likely that proper torque was not applied to the oil cooler (due to thread/ block contamination) than cooler warpage being the culprit.
Reply
Old Jul 5, 2021 | 01:58 PM
  #22  
Mohammad C's Avatar
Newbie
 
Joined: Jul 2021
Posts: 2
Likes: 0
2013 mercedes s350 bluetec
Originally Posted by GoodByeHonda
Can you please do us a favor and check the oil cooler with straight edge when you remove it?
imo it is more likely that proper torque was not applied to the oil cooler (due to thread/ block contamination) than cooler warpage being the culprit.

the torque for the oil cooler bolts was done with a torque wrench and based on the book. The first time doing the seals I bought a new oil cooler from the local MB dealer along with the seals but did not use it. When placing the new oil cooler on a flat surface it would wobble as did my old one. So I figured it was normal—although strange. I have seen a lot of chatter about oil coolers failing as well due to warpage.
Reply
Old Jul 5, 2021 | 04:03 PM
  #23  
GoodByeHonda's Avatar
Senior Member
 
Joined: Jan 2013
Posts: 305
Likes: 42
W211 E320 Diesel OM642
Interesting. The only thing I can think that would affect the torque would be not cleaning the block holes. Given a rather low torque required on those bolts, I can't imagine taking these bolts off the oil cooler in some specific order would make any difference.
ive heared of a suggestion however to heat up the new seals slightly just before installation but oil cooler seals leaking shortly after exchange is rather rare event.
Reply
Old Jul 6, 2021 | 12:47 PM
  #24  
B34chBum's Avatar
Senior Member
5 Year Member
Liked
 
Joined: Mar 2017
Posts: 258
Likes: 50
R320, Astro, JSW, ST4
If/when I do this job I will use a sealant along with the o-rings.
There's a non-hardening one I use to seal the camshaft seal uppers on the VW PD motor, for got the name/links to it.
It is brushed on from a small can - would be tempted to do all machined surface mating with the cooler.
Reply
Old Aug 18, 2021 | 08:27 AM
  #25  
kkarb's Avatar
Member
5 Year Member
Liked
 
Joined: Jan 2016
Posts: 121
Likes: 31
w164
I hadd the same problem. W166, ML350. Replaced oilcooler and seals 1 year ago. Still dripped a bit engine oil in rear right side of engine. To me it was the pedestall / beam gasked leaked. Dripped down at right side off the bellhousing. I removed the turbo once again, and replaced the pedestall / beam seals. One under beam an one between beam and turbo. I used a iphone endoscope to locate te leak, it was hard to detect. Se my pictures, its from the right side off the turbo pedestall.



Reply


You have already rated this thread Rating: Thread Rating: 0 votes,  average.


All times are GMT -4. The time now is 05:53 AM.

story-0
6 Mercedes Models That Did NOT Age Well (But Are Somehow Still Cool)

Slideshow: Not every Mercedes design becomes timeless, some feel stuck in the era they came from.

By Verdad Gallardo | 2026-05-12 18:09:07


VIEW MORE
story-1
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun

Slideshow: Yes, Mercedes built manual cars, and some of them are far more interesting than you'd expect.

By Verdad Gallardo | 2026-05-02 12:36:58


VIEW MORE
story-2
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren

Slideshow: A one-of-one U.S.-spec Mercedes-Benz SLR McLaren Roadster became even rarer after a factory-backed transformation at McLaren's headquarters.

By Verdad Gallardo | 2026-04-29 11:19:28


VIEW MORE
story-3
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine

Slideshow: Before curves took over, Mercedes mastered the art of the straight line, and some of those shapes still look right today.

By Verdad Gallardo | 2026-04-25 12:05:49


VIEW MORE
story-4
Flawlessly Restored Mercedes 190E Evo II Heads to Auction

Slideshow: The 190E Evolution II shows how a homologation necessity became a six-figure collector icon.

By Verdad Gallardo | 2026-04-22 17:53:47


VIEW MORE
story-5
Electric Mercedes C-Class Unveiled: 11 Things You Need to Know

Slideshow: Mercedes is turning one of its core nameplates electric, and the details show just how serious this shift is.

By Verdad Gallardo | 2026-04-21 13:58:06


VIEW MORE
story-6
Mercedes EQS Gets A Major Update: Everything You Need to Know

Slideshow: Faster charging, longer range, and a controversial steer-by-wire system define the latest evolution of Mercedes-Benz EQS.

By Verdad Gallardo | 2026-04-15 10:35:34


VIEW MORE
story-7
5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve

Slideshow: These overlooked Mercedes-Benz models never got the spotlight, but they quietly delivered more than most remember.

By Verdad Gallardo | 2026-04-13 19:35:45


VIEW MORE
story-8
Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping

Slideshow: A well-used 1991 Mercedes-Benz 300D with more than one million miles is now looking for a new owner, and it still appears ready for more.

By Verdad Gallardo | 2026-04-10 10:05:15


VIEW MORE
story-9
10 Most Reliable Mercedes-Benz Models You Can Buy Used

Slideshow: From bulletproof sedans to surprisingly tough SUVs, these Mercedes models proved that the three-pointed star can go the distance.

By Verdad Gallardo | 2026-04-08 09:55:49


VIEW MORE