Mercedes 2013 e350cdi oil leak, possibly oil cooler seals?!

[asg1980]

Hi

I have just purchased an E350cdi coupe, jan 2013 registered. 81k miles.

I have noticed a few spots of oil on my driveway and seems to be getting worse.

I checked under the bonnet and there is oil underneath the air filter batwings, a little under the turbo seals and also at the back of the engine I can see oil stains on the silver heat shield. Pics attached

Does this look like the oil cooler seals have gone?

Thanks in advance

 

[Smiley]

If you have drips of oil underneath then it is almost certainly the oil cooler seals that have gone. The oil cooler sits all the way at the bottom in the middle of the V so the misting and or leaks that you have photographed are nothing to do with the oil cooler - but all that collection of intake related "stuff" that sits in the V will have to come out anyway to get to the cooler. Best to get the undertray off and have a look from underneath to see where the oil is running down from. By the time you have bought the oil cooler and a bunch of new gaskets and seals for the intake components the parts bill will be £3-400 and expect a total bill of a bit over £1,000 if someone else is doing it. It would be well worth cleaning the manifolds whilst they are off; it is a messy job though. Don't even think of a main dealer the bill will be £££££££

 

[Smiley]

ps now you know why the previous owner sold it.

 

[TeddyRuxpin]

That will be the green o-ring on the turbo inlet pipe. This is not oil cooler seals, that leak would be from under the car. It costs a few quid to DIY or relatively cheap to get this problem sorted at an indie.

Change the black o-ring on the other end of the pipe and all the orange seals on the turbo too. Cheap.

 

[OneForTheRoad]

As above , plus 2013 car , pretty sure it'll have the purple oil seals.

Check the pcv pipe on the left is also seated correctly. It too may need renewing. These engines vent oil mist from the crank shaft directly through the pcv and then into the turbo , over time oil drips from the turbo seal . The swirlflap motor sits directly underneath these drips .

If you remove the batwing you'll be able to see and check all of the above and what teddy mentioned.

 

[asg1980]

If you have drips of oil underneath then it is almost certainly the oil cooler seals that have gone. The oil cooler sits all the way at the bottom in the middle of the V so the misting and or leaks that you have photographed are nothing to do with the oil cooler - but all that collection of intake related "stuff" that sits in the V will have to come out anyway to get to the cooler. Best to get the undertray off and have a look from underneath to see where the oil is running down from. By the time you have bought the oil cooler and a bunch of new gaskets and seals for the intake components the parts bill will be £3-400 and expect a total bill of a bit over £1,000 if someone else is doing it. It would be well worth cleaning the manifolds whilst they are off; it is a messy job though. Don't even think of a main dealer the bill will be £££££££

I will get the undertrays off and try to see where the oil is coming down from. I just saw a video on YouTube, a guy with a c350 cdi, said he had a leak from the turbo seal and pcv seal which caused the oil to drip down the back of the engine on to the floor and he said it wasn’t the oil cooler seals, as once he replaced those seals there were no longer oil stains on the floor

Thank you for the advice regarding costs etc very helpful

 

[asg1980]

That will be the green o-ring on the turbo inlet pipe. This is not oil cooler seals, that leak would be from under the car. It costs a few quid to DIY or relatively cheap to get this problem sorted at an indie.

Change the black o-ring on the other end of the pipe and all the orange seals on the turbo too. Cheap.

As above , plus 2013 car , pretty sure it'll have the purple oil seals.

Check the pcv pipe on the left is also seated correctly. It too may need renewing. These engines vent oil mist from the crank shaft directly through the pcv and then into the turbo , over time oil drips from the turbo seal . The swirlflap motor sits directly underneath these drips .

If you remove the batwing you'll be able to see and check all of the above and what teddy mentioned.

Thanks guys. I think I may attempt this first as sounds relatively easy to do and see how I get on.

Will keep you posted on my progress in the coming days

Thanks

 

[TeddyRuxpin]

Sorry, it's an outlet pipe to the intercooler, not an inlet.

In any case if you google or search for OM642 'green o-ring' you should get some results and tutorials. It's a bit tricky to refit without damaging the new o-ring so buy a few, and change the black one on the other end too. All the orange ones with all that oil around it too.

Enjoy the research

 

[asg1980]

Yes, I thought that’s what you meant and thanks for the tip regarding refitting the pipe

 

[asg1980]

Sorry, it's an outlet pipe to the intercooler, not an inlet.

In any case if you google or search for OM642 'green o-ring' you should get some results and tutorials. It's a bit tricky to refit without damaging the new o-ring so buy a few, and change the black one on the other end too. All the orange ones with all that oil around it too.

Enjoy the research

I managed to change all these seals and the 2 o rings today. That lower bolt on the resonator was a b@!!h lol otherwise an easy job. Hopefully no more leaking oil but will check over the next few days and see if the leak has stopped. If not, then it will most likely be the oil cooler seals, fingers crossed it’s all good now though thanks guys

 

[TeddyRuxpin]

Great job! Yes, that bolt on the lower resonator is well hidden - need a good flexible & extendable wrench

 

[asg1980]

Great job! Yes, that bolt on the lower resonator is well hidden - need a good flexible & extendable wrench

Ha you’re not wrong, getting the right extender and wrench was the issue, a lot of improvisation for that was needed!!! But all sorted now thankfully.

 

[pikapika33]

Can you recommend a suitable flexible extendable wrench?