Om642 oil leak soon?

[MartiniNight]

Quick question;
Hello I've got an January 2010 built w219 with a om642 diesel engine with 117k miles on the clock.
These engines are well know for the oil cooler leaks,when i bought the car with 100k miles on the ckock i was told to replace the oil cooler seals as they only last 80k miles and to expect a "oil cooler leak soon" ,well that didn't happen ,no leaks yet.
Why some om642's leak as soon as 70k miles and others like mine 117k miles and no leak??
If anyone knows the answer, many thanks

 

[MrGreedy]

Maybe the seals have been replaced since new but you're just not aware? Do you have provenance from new?

 

[MrGreedy]

To add, I would speculate it's due to intermittent excessive high heat load, causing slight movement in the cooler itself, allowing many cycles of micro warping under heat load and some oil getting into a fine crack. This then dries and bakes. Then another period of high heat load, micro warping, some more tiny film of oil, then baked dry.

Repeat over many miles, and the cooler gets slightly jacked away from the mating surfaces.

So it could be possible that cars that suffer high heat load are more susceptible. Does this mean stop start traffic and DFP regens whilst stationery vs a car that has been in less congested areas for most of it's life? Is a life cruising on the motorway more benign or a life cruising rural non congested roads at 50mph or sitting in traffic in a major city?

I don't know the answer, but I would guess the above could be a factor.

 

[MartiniNight]

Maybe the seals have been replaced since new but you're just not aware? Do you have provenance from new?

As far as I'm aware car still has it's original orange seals as i couldn't find any "oil cooler replacement" recipt in the car's paperwork.
The car does has full history , including oil changes every year since 2011 maybe that's the answer??

 

[MartiniNight]

To add, I would speculate it's due to intermittent excessive high heat load, causing slight movement in the cooler itself, allowing many cycles of micro warping under heat load and some oil getting into a fine crack. This then dries and bakes. Then another period of high heat load, micro warping, some more tiny film of oil, then baked dry.

Repeat over many miles, and the cooler gets slightly jacked away from the mating surfaces.

So it could be possible that cars that suffer high heat load are more susceptible. Does this mean stop start traffic and DFP regens whilst stationery vs a car that has been in less congested areas for most of it's life? Is a life cruising on the motorway more benign or a life cruising rural non congested roads at 50mph or sitting in traffic in a major city?

I don't know the answer, but I would guess the above could be a factor.

Hi,yes the car has DPF and its a motorway car.
Dpf regens happens mostly when the car is being driven as i know when dpf regen is takin place as revs and gear changes do at 3k revs for 15 min or so while im on motorway ,only a couple times happened while stationary.
Very rarely i take the car to city centre's

 

[johnsco]

My year 2009 W211 E280 cdi estate has the 642920 engine.
It's now at 185,000 miles.
I've owned it from 111,000 miles.
It's never has oil cooler seal leak while I've owned it.
I've just checked its (incomplete) previous service history and see no reference to oil cooler seals there.
When the seals fail - as they well might - Is it a new oil cooler or is it new seals ?
Post #4 refers to orange seals - presumably the originals.
Is this easy to check ?
I've never looked and I'm not sure where to look.
Any info appreciated.
Thanks.

 

[MartiniNight]

My year 2009 W211 E280 cdi estate has the 642920 engine.
It's now at 185,000 miles.
I've owned it from 111,000 miles.
It's never has oil cooler seal leak while I've owned it.
I've just checked its (incomplete) previous service history and see no reference to oil cooler seals there.
When the seals fail - as they well might - Is it a new oil cooler or is it new seals ?
Post #4 refers to orange seals - presumably the originals.
Is this easy to check ?
I've never looked and I'm not sure where to look.
Any info appreciated.
Thanks.

Hello, this is the information i was told;
-the orange seals are the originals,the ones who have a tendency to leak at high constant engine temperatures over the years.
The purple seals are the upgraded ones ,normally found in cars 2012+.
This is the ones you need to buy if yours are leaking.
When the seals leak,you only need to change the seals but the seals are deep inside the engine so it's a day's job..
One way to check if they are leaking is to check for oil underneath the engine belly between the engine and gearbox, or oil in the coolant reservoir..but this may be not 100% acurate as oil can come from anywhere really.
When the oil seals leak you will know as youll find a big puddle of oil underneath the car and your oil consumption will drop,you will know straight away,This i was told.
Some om642's leak,and some don't

 

[johnsco]

Thanks MartiniNight.
I've never seen any trace of oil underneath the car (although I guess the undertrays might hide this until it gets very serious).
Also - There's no trace of oil in the coolant tank.
Fingers crossed !

 

[Larkone]

They will tell you if it is leaking at the MOT as oil leaks are reportable now.

 

[AndrewOl]

The oil cooler seals are a common failure but that doesn’t mean they all fail. As they are buried in the v it is well worth changing them if you are in there for another reason (swirl flap motor- another common one). If it isn’t leaking then I would leave it alone. Don’t worry a 12 year old MB will soon present another opportunity to lighten your wallet!

 

[unclebuck]

And then there is a plethora of jobs that can be checked and done when its all apart.

 

[wilko50]

Quick question;
Hello I've got an January 2010 built w219 with a om642 diesel engine with 117k miles on the clock.
These engines are well know for the oil cooler leaks,when i bought the car with 100k miles on the ckock i was told to replace the oil cooler seals as they only last 80k miles and to expect a "oil cooler leak soon" ,well that didn't happen ,no leaks yet.
Why some om642's leak as soon as 70k miles and others like mine 117k miles and no leak??
If anyone knows the answer, many thanks

I have same engine, I am up to 160k and its been fine so far, had the car 11 years

 

[W1ghty]

I’ve often wondered what the highest mileage non oil cooler leaking OM642 is out there ?
Im on 129k on a 2009 with no leak .