Did you check to see if the leak is not coming from the little pipe with seals that is connecting the intake manifolds ( the little 1 inch connector with O rings). Another sourse, much easier to fix could be the gasket under the EGR or the sensor located on the driver side on top of the intake manifold.
Oofff. Coolant can leak from many areas after oil cooler seals replacement.

In my case, I did the repair a little while ago and I still have an oil leak.
The oil drips at the bottom of the bell housingdrainignfrom the left side .
The little drain hole on left is dry. I took a seringe a poured some water in the V valley and to my surprise water came down the bell housing and not the drain hole on the left. I am suspecting the gasket under the turbo piedestal or ... main seal.
I am drained of ideas or energy to mess with this.
By the way, do you have the torque specs for the 4 bolts conencting the turbo piedestal to engine block? I used 20Nm but I don't think is right.

I hope that by now you found your problem and had it fixed, easily.

All the best.

 

How much water exactly did you pour and where did you pour it (in front of the turbo?). I asked coz there is a 1 inch "wall" that separates the oil cooler and the turbo section.

 

Catalind - You guessed it right. I just finished this evening. I don't know how I did it but one of the o-rings was pinched out of the groove on that little crossover piece. I must have jostled it when I put it in the first time. After replacing the oil cooler seals, I had to take the whole thing apart again to replace that o-ring. I searched for the source of the leak for hours. It was on the bottom fuel filter side of the crossover and dripped on the floor the same place as the oil cooler leak.


Shame on me - I didn't have the torque specs so I used my little 6" rachet and popeye forearms. Spot torque is what we called it in the Navy. I saw spots after tightening each of them.


I have 160k on this 2008 ML 320 CDI. I'm just hoping to get another 40k out of it.


Thank you for the reply. I was really stumped.

 

My independent is telling me they need a tool to reinstall the turbo, which only the dealer has. Has anyone heard of this?? I have the same oil cooler leak issue.

They are telling me they can't get the turbo alignment tool needed to reinstall the turbo...

Anyone?

 

There is no special tool require to reinstall the turbo. Normal hand tools that anyone that specializes in MB will have; Torx, ratchets that adjust in the middle of the handle, torque wrenches, etc.

 

That's bs! I did tons reasearches and watched video/photos and services manuals back then.there is no special tools needed

 

Before changing the oil cooler seal there is another oil leaker that needs to be checked. Look at the orange gasket that connects to the turbo inlet. It is the one that goes to the y plastic piece on top of the intake; comes from air filter boxes. The PCV system breathes into this duct and oil will collect into the turbo inlet. If the seal is trashed, oil will leak around it, down to the swirl motor and to the v6 valley. From there it will makes its way to the floor giving an indication of a bad oil cooler seal.

 

Everyone told me I needed a oil cooler seal.
They told me even more after I had a loose oil cap.
New oil cap, cleaned up engine and a few months for the last pit of oil to work through, and now no more need for an oil cooler seal.


HMmmmmm?????
Wonder how many unneeded oil cooler seal replacements have been done?

 

Has anyone tried using an oil additive to stop leaks?

Advisable? not advisable?

 

If the seal is truly leaking a oil additive is what you use to sell the car to an unsuspecting buyer.


If the seal is just weeping slightly, the sealant might work, but also is hard on filters and small passages.

 

A month ago we had to have the swirl motor in out 2009 GL320 (90K miles) replaced at dealer. Since then, we have had intermittent burnt plastic smells from engine bay. I have it in for service diagnosis on that smell and symptoms of other issues, service advisor says oil cooler is leaking and needs to be replaced ($2,700).

My question after reading all these helpful DIYs is could their tech, in replacing the swirl motor, have disturbed or otherwise caused hoses into/from oil cooler to start leaking?

The other hits in this visit to dealer: transfer case needs to be replaced ($6,600), front air suspension leaking, needs bags replaced ($3,200), right front wheel bearing ($990), and rear brakes (no sure of cost b/c I didn't ask — I can do rotors and pads in an easy afternoon.)

Hoping our aftermarket extended warranty will cover transfer case, wheel bearing, air springs and oil cooler, but not holding my breath. We've been left holding the bill on aforementioned swirl motor and before that, AdBlue tank replacement because they were not covered.



TIA

 

What warranty do you have?

 

I can't remember. The folio is in the car at the dealer. Our SA has all the info from our numerous attempts in vain to date to collect on repairs.

The policy was $4,500 when we bought the GL in 2012. If it doesn't come through this time, it was a tough lesson learned.

 

+1 member in "om642 oil cooler leak club"

Every morning under the car there was oil leak, with size of a coin, after months "two coins"... and last... looses 1liter oil per day.
Common issue with oil cooler leak on om642. Cheap parts, but hard work.

My advice is to use service/garage with "know-how" about Mercedes engines/issues. Better more money, than bad engine assembly!

I attached photo of the engine, after removing all parts, clear V-shape. You know how it looks like without cover.. you can't see V-shape.

It's cost of me $300($100 parts, $200 work) and 3 days without car.
Now i'm on test period, i hope no more oil leaks i next few years.

 

You did it yourself? If not, where did you get it done for $300?

 

I'm in Bulgaria, South East Europe. I went in local service garage which repairs MB cars.
Unfortunately, in Bulgaria, official Mercedes dealers are deceivers, impostors, cheaters

 

After removing all the underside panels and felt soundproofing from my oil-soaked '08 320 I finally sourced the leak. Looks like I too have joined the leaking oil cooler seal club . For those trying to diagnose, look for the weep hole just above the transmission lines at the rear left side of the block. Oil from this comes from the "V" and likely puts you into this club as well. Here's a picture of the weep hole.

I ordered an OM642 oil cooler seal kit from IDparts that claims to have all the parts needed for the task, including the improved purple viton seals.

 

I have this same issue on my 2012 GL, second time around, first time was within 6 weeks from new, the car was sent back to the dealer for repair. I now have 115,000 kilometers on the engines, dealer maintained, last service was late and I have the 7 years Mercedes extended warranty. The dealer has not returned two voicemails asking if my warranty covers this work, I called Mercedes Customer care in Vancouver and the person I spoke to had no clue what I was talking about, again no one returned a call, I will try again to find out of Mercedes will repair the oil cooler seals, I was quoted $5027.52 for parts and $2559.20 for labour (worst case scenario)

 

Does that quote include a bucket of Vaseline?

I'm currently starting to button up my '08 320 after replacing the seals, and the whole job is going to cost me about $C200.00 INCLUDING the service manual I found on eBay, a set of star drive sockets, a pair of click-lock pliers, and a #45 Torx socket (to remove turbo pedestal). I bought a seal kit from IDparts, and spent another few bucks at my local MB dealer for EGR and Y-tube gaskets, a new intake seal, and a replacement clip to attach the servo to the RH bank of mixer valves (it WILL break when you try to remove it).

Sadly, I found the new purple Viton seals were already installed, but the monkey who did the job (B4 I bought the car) didn't torque the thing down properly, allowing it to leak. He also crushed and tore the intake seal when putting the intake plenum back on, and broke the rear RH tab on the air box.

Bottom line, unless the job is outside my skill set or comfort zone, I never let "technicians" touch my stuff. This latest example just confirms that feeling. Do it yourself, and then you'll know it's been done properly.

The whole job takes a few days, and a lot of paper towels and vinyl gloves, but it is doable. I read these outlandish quotes and stories about how you need "special" tools etc to install the turbo (unless they're referring to $2.99 #45 torx socket needed to R&R the turbo pedestal) and I just shake my head. Get a service manual, set aside some screen time, and take lots of pictures. OTOH, if MB welches on the extended warranty, bring your car over to me on the Island and I'll do it for half that!

If there's interest, I'll post pics when done but they're already easy to find on some excellent earlier posts.




The culprit, deep in the belly of the beast.

 

Well, the car is fixed, Mercedes stood by their product and repaired the seals under warranty. The dealer I have used for most of the services was recently taken over by a larger company and they were no longer interested in the work so I called the dealer where I bought the vehicle and they were only too happy to help.

 

Just finished the Oil Cooler seal replacement on my 07 om642, with the exception of the 2 t45 bolts the attach the turbo to the pedestal. I believe they are a pretty high torque, however I don't have the exact value.

Can anyone help with this??

 

Torque Spec of the T45 Torx bolt for the oil feed pedestal to turbocharger Stage 1 30 nm and Stage 2 50 nmm

 

Hi all,
looks like I might be joining the engine cooler repair club soon. Wife notice oil in garage, so I took a look. I cleaned all oil from underside of tranny/motor and checked after a short trip. Bottom oily again but no oil by the famous drain hole. Had MB dealer look at it as well. They say oil cooler and want 2500 + tax for it.

Is the drain hole the only place for the oil to escape the belly of the beast or can it run overtop and down on each side of bellhousing?

Greetings from Kelowna in Canada

 

If the oil is not coming through the weep hole, and the hole isn't plugged up, I would think the leak may be from elsewhere. There's a dam in the V at the back of the block designed to divert the oil through the weep hole. Run a long pipe cleaner or whatever through the hole from below to ensure it's clear. If the oil still comes around the bell housing and not through the weep hole, I'd start looking elsewhere. Start with the turbo pedestal, valve covers, and the seal where the PCV valve mounts into the back of the RH valve cover.


No way oil can leak from cooler without exiting here (unless plugged)

 

THANKS HARBRO
I'll try to find out if hole is plugged up once I get back home in 13 days. Doing construction on a 14/7 rotation.