Turbine leak

[FlavioM]

Hi, looking at the engine today I noticed this

I cannot see very well because it is in a difficult position, but it seems that the turbine joint is leaking something, maybe oil?
What could be the reason? Is it dangerous to keep on driving the car like this?

Thanks!

 

[Noddy 99]

My guess is that it's coming from your PCV valve and pipe. A faulty valve doesn't separate the oil coming from the crankcase and the suction from the turbo sucks it up the pipe and into the intake manifold. You'll only know how oily it is by taking off the intake into the turbo and inspecting the amount.

It's happening (in a minor way) on my car so I'm going to replace the valve. In the meantime, I'm driving it perfectly happily. If left unattended, it will drip down and foul your swirl flap motor but others will have to advise you on what effect it will have on your turbo.

 

[Mark A]

I would start by changing the 2 orange seals (turbo & PCV). Cheap enough from dealer and easy to change yourself . I changed mine today whilst I had the batwing off to change the air filters. Worth changing it when doing routine servicing.

 

[FlavioM]

Thanks guys.
I saw that the PCV valve Is not that expensive, so i was considering to replace it.
Is it a difficult job? Possible to do it on my own?

 

[Noddy 99]

Very possible. Just move the driver side air filter and you'll have access to the bolts (3, I think).

Several videos on YouTube...

 

[LostKiwi]

Very common issue on the 3L V6 turbo diesel.

 

[Doug1234]

If you are trained as a gynaecologist then replacing the seal (part no A0149977146 ) on the fitting on rear of head will stop all the oil fumes , did this on mine when doing turbo change and it completely sorts problem out.
No need for catch cans just take it back to stock. Video shows the unit and seal.. use torx ring spanner to get access from above and you may have to loosen some cam cover bolts to ease it out.

 

[mioba]

the beloved pitfalls of the OM642.

Before shelling out on a PCV, replace the batwing seal (to turbo) and the smaller seal to the PCV. It will be clear when you take it apart.

These two items should be service items and be sure you change them every couple of years. If not you will be shelling out big money for swirl flap motor replacement. In the second pic it already looks wet beneath the wing. Get it cleaned up asap....

The bigger seal flattens over time and its clear your fumes are escaping at the turbo manifold. The ribs on the smaller seal become worn also.
Good idea to change the pcv at 10 years mind. the diaphram hardens and does lots of work.

No need for catch cans or other mods.

Buy genuine all the way.


I changed the PCV on my w251 last year....what a beach of a job.

 

[Noddy 99]

If you are trained as a gynaecologist then replacing the seal (part no A0149977146 ) on the fitting on rear of head will stop all the oil fumes , did this on mine when doing turbo change and it completely sorts problem out.
No need for catch cans just take it back to stock. Video shows the unit and seal.. use torx ring spanner to get access from above and you may have to loosen some cam cover bolts to ease it out.

If you're looking for this on the web or YouTube, this is called the PCV valve COVER. I've ordered one, knowing that they're a bit tricky to fit. I'm hoping that a well-positioned lamp and an extending mirror will make it possible...

They're actually pretty difficult to source; don't know why...

 

[Doug1234]

Just buy the seal , only takes a couple of minutes to get the old one out and new fitted

Pardon our interruption...

www.ebay.co.uk

 

[FlavioM]

Ok guys many thanks for your suggestions.
My car has around 100k miles and I don't have any idea of its maintenance history. So what I was thinking to do is to replace both the PCV valve (A6420101891) and the seal of the PCV cover (A0149977146), as well as of course the turbine seal (do you have the part number by chance..?).
Still not sure whether to do the work by myself or buy the parts and have a mechanic to replace them

 

[mioba]

Get the parts from a dealers based in the vin.

Just tell them what you need at the parts desk.

Don't relly on ebay overpriced stuff.

If you are tecnically competent with car maintenance its all easy but time consuming.

You really need to get below the batwing cleaned up.

 

[FlavioM]

I just realised something that is making me a bit anxious... Looking at the 3rd picture it seems that there is something like a gummy paste around the joint between the batwing and the turbo (tried to touch it and it is hard)... This makes me think of two different scenarios. The 1st one is that a lazy mechanic or a lazy previous owner saw the oil leak in that point and couldn't be bothered properly fixing it, so tried to seal it that way. The 2nd is that there is a crack in the batwing that someone tried to patch up in that way...
Hopefully is the 1st scenario, otherwise it might get more expensive than I thought...

 

[mioba]

No point worrying, it will reveal itself when you take it all apart.

But you are correct, looks bit messy there, there it should be a uniform collar and all you see is the silver jubilee clip and slight orange ring of the seal.

Speaking of the jubilee, these shouldn't be overtightened - they are cleverly marked as to a tightenig limit on the elbow.

But they do get overtightened breaking the elbow, the batwing is actually a poor design by merc, plastic directly connected to a hot turbo - leads to brittle plastic.

if it is broke - new batwing (MAFS are built in) - expensive plastic

 

[FlavioM]

Hi guys, tomorrow I have got an appointment with the mechanic to replace one suspension and a few spark plugs. These works are paid by the dealer who gave me a 1 year warranty on the car, and must be done through his mechanic.
Since I also wanted to service the automatic transmission, I thought I'd to that in a Mercedes service point. So today I called to make an appointment and I also told the guy at the phone about the oil leak. He said straight away that the cause is the heat exchanger (a common issue in this engine, he said) and that to fix it it would cost roughly 2k!!!
So now I am a bit confused. The Mercedes guy didn't see the car nor the pictures, but he sounded quite sure of what he was saying.
I was thinking to ask tomorrow the dealer's mechanic for his opinion as well.

 

[LostKiwi]

Run as fast as you can from the Mercedes service point. Oil cooler leaks are an issue on some OM642s but the leak is low down in the V not on the batwing.
The oil cooler seals are £800-900 from a decent independent specialist.
Even my R class (which is a proper bar steward to work on) is under £1000 from an independent.
The batwing seal is DIY if you fancy giving it a go. Plenty of how tos on YouTube.

 

[FlavioM]

Yeah that's what I thought, I am no mechanic but how can it be the oil cooler if it's positioned below the leak?

Anyway, in case the batwing is cracked, is the only option to replace it, or is there a way to fix it?

 

[FlavioM]

Here i am.
So, Yesterday i went to the dealer mechanic to replace a suspension and a few spark plugs. He removed the batwing and this is how It looks like



So i Guess only option Is to replace the whole batwing...
I found a second hand genuine one for 250 (in good conditions), or otherwise there are not-genuine brand new ones for 150. What's your advice?

 

[Noddy 99]

I don't know where the OP has got to by this point but I thought I'd update on the PCV valve issue.

Just replaced the PCV valve AND the cover at the rear of the head. The valve itself is a doddle to change - just 3 bolts. The cover is a bit more laborious, only because the bolts are facing the bulkhead. However, with an 8mm socket on a ratchet, they are VERY easy to remove. It will take a good few taps with a mallet and pry bar to dislodge the housing but it's not a huge problem.

Haven't taken the car on a run yet but it started first time with no codes.

 

[mioba]

Here i am.
So, Yesterday i went to the dealer mechanic to replace a suspension and a few spark plugs. He removed the batwing and this is how It looks like

View attachment 74131 View attachment 74132

So i Guess only option Is to replace the whole batwing...
I found a second hand genuine one for 250 (in good conditions), or otherwise there are not-genuine brand new ones for 150. What's your advice?

Go genuine buddy.

The MAFs are part of the batwing. Last thing you want is crappy MAFs.

Make sure its all complete and working.

Get all that oil cleared out before it starts eating into the motor below. Get new seals - genuine.

ps make sure the replacement bat wing has the same pn or updated. there are many versions.

To be sure and if you want to spend more, get to a dealer with your vin.

that inlet manifold needs a good clean too. its orange seal to metal turbo manifold. looks like the po or some rogue garage just hammered it with sealant