E350 Cdi OPM642 NS Lower Engine Leak

MrGundam

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Hi Guys,

Just noticed this and wonder if anyone know where this might be likely leaking from?

vVi6SPx.jpg

NZeC8G8.jpg


Are those 2 pipes the diesel lines?
 
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malcolm E53 AMG

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Oil cooler seals in the vee of the engine in all probability what mileage is the car on the seals generally need replacing circa 100k miles
 
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MrGundam

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Oil cooler seals in the vee of the engine in all probability what mileage is the car on the seals generally need replacing circa 100k miles
its 120000 but its a 2012 where I thought they had the upgraded purple seals.

I'll have a dig around with bore cam soon
 

malcolm E53 AMG

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The engine oil fills the vee then eventually starts to run down the back of the block where the gearbox mates. If it is the seals you will want to get it sorted ASAP how much are you losing by looking at the dipstick
 
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MrGundam

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I am hoping it was the oil cooler seals as despite being a 2012 model it had the old orange seals. Not too bad a job but waiting for postage on parts over Christmas and new year was bit of a pain.

 

SmartAmg

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Mine goes in tomorrow for the same thing. :rolleyes:
 

greenfingers

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I've been away from the fold for a few years and am looking to get back into a Mercedes with this engine. Any pointers about common problems and what to look for would be greatly appreciated. I was aware of the oil cooler seal issue, but had read that the more durable viton seals were fitted from 2010 onwards and that these didn't degrade and cause leaks - is that wrong? I've been trying to find a circa 2013 CLS Shooting Brake, most of which have done around 100k miles and now I'm wondering if this problem is likely to raise it's head at that kind of mileage.

Since my last ML, I've had 2 BMWs with the N57 (3.0 diesel) engine and am fully conversant with their common issues (intake manifolds and EGR coking up, valve cover gasket leak and oil filter housing/cooler gasket leak). I've done each of these jobs myself at various times and none has taken me more than a day. Presumably with the OM642, you should do the intake manifolds at the same time as the oil cooler, but that's quite a big job (maybe 10 hours?) and a lot of seals to replace. Also, what about the turbo seals - don't they start leaking too?
 

mioba

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turbo seal should be a service item - they become distorted because of the plastic manifold they sit in connected to a hot turbo.

Lots on the forum about OM642 and its nuances.
 

malcolm E53 AMG

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Regarding the oil cooler seals I’ve yet to hear of any purple Viton seals being fitted to any of the cdi engines in the UK. MY E350cdi estate (12 plate) is on 80k miles and the oil cooler seals are just starting to weep so no doubt it will require the work doing <100k miles.
Some just replace the seals on the OM642 others also replace the inlet port motor, clean the inlet manifolds and even replace the oil cooler with a new unit depends on how much you want to spend and whether the car will be a keeper. The turbo seals are an easy job just remove the batwing from the air filters and push the new ones in.
 

mioba

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Regarding the oil cooler seals I’ve yet to hear of any purple Viton seals being fitted to any of the cdi engines in the UK. MY E350cdi estate (12 plate) is on 80k miles and the oil cooler seals are just starting to weep so no doubt it will require the work doing <100k miles.
Some just replace the seals on the OM642 others also replace the inlet port motor, clean the inlet manifolds and even replace the oil cooler with a new unit depends on how much you want to spend and whether the car will be a keeper. The turbo seals are an easy job just remove the batwing from the air filters and push the new ones in.
and need spider fingers to get the pcv seal seated (also should be service item) and then get the horrible manifold aligned with the air filters / turbo and pcv.

The batwing houses the mafs (not seperate) so if a MAF fails its 800 quid.
 

greenfingers

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Regarding the oil cooler seals I’ve yet to hear of any purple Viton seals being fitted to any of the cdi engines in the UK. MY E350cdi estate (12 plate) is on 80k miles and the oil cooler seals are just starting to weep so no doubt it will require the work doing <100k miles.
Some just replace the seals on the OM642 others also replace the inlet port motor, clean the inlet manifolds and even replace the oil cooler with a new unit depends on how much you want to spend and whether the car will be a keeper. The turbo seals are an easy job just remove the batwing from the air filters and push the new ones in.
Thanks Malcolm. Your car is the sort of vintage I'm considering, so that's very relevant. If I buy a car that needs the work doing, any idea what an indy would charge for doing the cooler and turbo seals, along with cleaning the manifolds and swirl flaps?

After cleaning my BMWs manifolds (and removing swirl flaps from one of them), I had the cars remapped and EGRs mapped out. My current one has done about 15k miles since then and the egr pipes and manifold are still pristine. I'm looking at a pre 9Gtronic, on the understanding that the 7 speed autobox can handle the torque better if the car is remapped to about 310bhp.
 

greenfingers

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and need spider fingers to get the pcv seal seated (also should be service item) and then get the horrible manifold aligned with the air filters / turbo and pcv.

The batwing houses the mafs (not seperate) so if a MAF fails its 800 quid.
It does sound a pesky lump to work on. Is the adblue system likely to be problematic too? I know it's not supposed to be tampered with, but don't people just get it deleted from the ECU to avoid those issues?
 

malcolm E53 AMG

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Thanks Malcolm. Your car is the sort of vintage I'm considering, so that's very relevant. If I buy a car that needs the work doing, any idea what an indy would charge for doing the cooler and turbo seals, along with cleaning the manifolds and swirl flaps?
I would imagine that would cost the thick end of £1k

All the cdi engines are EU5 the ‘d’ suffix is used for Adblue EU6 cars

I won’t buy an EU6 diesel too many problems when you introduce ADBLUE I’ve just bought one petrol car and I’ll be replacing the E class with a petrol when the time comes. The OM642 is a great engine and essentially very reliable in EU5 guise (it’s been in production 15+ years) so very happy with mine
 
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Uncle Benz

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and need spider fingers to get the pcv seal seated (also should be service item) and then get the horrible manifold aligned with the air filters / turbo and pcv.

The batwing houses the mafs (not seperate) so if a MAF fails its 800 quid.
Mercedes do offer a service exchange batwing for about half that (not much consolation), but they won’t routinely tell you that. They’d much rather sell you a brand new one.
 

mioba

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True the mb reman site is great but certainly kept under the radar by MB. If you don't know about it - its easy to spend big money.
 

boxer 01

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I've been away from the fold for a few years and am looking to get back into a Mercedes with this engine. Any pointers about common problems and what to look for would be greatly appreciated. I was aware of the oil cooler seal issue, but had read that the more durable viton seals were fitted from 2010 onwards and that these didn't degrade and cause leaks - is that wrong? I've been trying to find a circa 2013 CLS Shooting Brake, most of which have done around 100k miles and now I'm wondering if this problem is likely to raise it's head at that kind of mileage.

Since my last ML, I've had 2 BMWs with the N57 (3.0 diesel) engine and am fully conversant with their common issues (intake manifolds and EGR coking up, valve cover gasket leak and oil filter housing/cooler gasket leak). I've done each of these jobs myself at various times and none has taken me more than a day. Presumably with the OM642, you should do the intake manifolds at the same time as the oil cooler, but that's quite a big job (maybe 10 hours?) and a lot of seals to replace. Also, what about the turbo seals - don't they start leaking too?
I have a w211e320cdi 2007 with the om642, the turbo seals kept leaking and I ended up fitting a silicone tee adaptor, which did away with the seals and no more oil leak. Engine and gearbox mounts seem to fail causing vibration and I would make sure the transmission has been serviced regularly.
I also tackled the oil cooler seals and at the same time decoked all egr pipework and manifolds. I was in two minds about getting rid of the swirl flaps as the linkages were worn, but ended up renewing linkages with aluminium after market ones. I am not a mechanic but in my opinion with the correct tools a competent methodical person is capable of doing the oil cooler seals, it's just time consuming the end result is very satisfying. Plenty of videos on YouTube.
 

boxer 01

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I forgot to mention after the oil cooler repair and decoke my car which has over 160,000 miles on clock runs like a dream.
I was going to invest in later model e class but they are notorious for adblue and nox faults so I decided to keep mine and I'm happy with it, at least I can fix most issues myself with the help of forum members.
 

alexanderfoti

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Mercedes do offer a service exchange batwing for about half that (not much consolation), but they won’t routinely tell you that. They’d much rather sell you a brand new one.
They only tell you, when they have no "new" stock :)
 

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