Hearing worrying things on the 250 diesel engine

Page may contain affiliate links. Please see terms for details.

Vlad

MB Enthusiast
Joined
May 30, 2003
Messages
2,411
Location
Reading, England
Car
Various Mercs come and go
Was thinking of buying a E250, but having spoken to somebody who works at MB dealership, I'm not so sure now.

He had some very damning things to say of them and advised me to stay clear.

1) Sump is plastic and he's had to replace a number of sumps on customers cars where other garages have over tightened the sump plugs and cracked the plastic.

2) Stretched timing chains (here we go again)...engine out as the chain is on the back of the engine.

3) Plastic water pump, which seems prone to failure.

Any thoughts or experiences of this engine......preferably on higher mileage examples
 
Was thinking of buying a E250, but having spoken to somebody who works at MB dealership, I'm not so sure now.

He had some very damning things to say of them and advised me to stay clear.

1) Sump is plastic and he's had to replace a number of sumps on customers cars where other garages have over tightened the sump plugs and cracked the plastic.

2) Stretched timing chains (here we go again)...engine out as the chain is on the back of the engine.

3) Plastic water pump, which seems prone to failure.

Any thoughts or experiences of this engine......preferably on higher mileage examples

Not sure about 1) and 2), but mine has just been in for a B service and the water pump was replaced. It's obviously a service bulletin as they seemed to expect it and replaced without making a big fuss. Car done 24k miles, 62 plate.
 
I also have a similar engine and MB replaced my water pump during service at 36000, under warranty, saying they had noticed a slight leak. I hadn't noticed anything or requested any checks.
If the water pumps are problematic, Ive not recall other posts about it, and don't know if the replacements have been improved.
 
I have the 220 on a 60 plate, bought it with 10k miles, now on 240k miles.

Had the water pump replaced at 215k miles paid for by Mercedes but was quoted £384 so not to bad.

Other than that is has been 100% with just routine servicing.
 
I have the 220 on a 60 plate, bought it with 10k miles, now on 240k miles.

Had the water pump replaced at 215k miles paid for by Mercedes but was quoted £384 so not to bad.

Other than that is has been 100% with just routine servicing.

Some serious mile munching there!
 
I think it's scaremongering
The first one I looked after was a 59 plate with well over 200k on it still ran very well.
I personally have seen no chain issues but apparently they are common????
I must look after at least 40 of these engines well over 100k without any issues, so that must say something about them?
Yep I've replaced sump pans and valve covers, but only due to breakage.
To be fair you are getting lucky with any modern day Diesel engine at around 250k
 
Some serious mile munching there!

My last 2 E220's before this one, an 03 and 07 both did 315k miles without issues. If you consider the number of 220/250's used in the chauffeur / private hire industry, timing chain issues are very rare.
 
Anything before 2008 will have the older OM646 engine with a double timing chain at the front of the engine. I suspect that the problem may be confined to early versions of the OM651 and Mercedes may have modified the timing gear in later engines. That said the location of the timing chain remains at the rear of the engine meaning an expensive repair should it go wrong.:dk:

a_OM_646__E_200_CDI__Motor_Solo_ab_Mopf.jpg
 
Has the current 220 still got a double chain located on the front of the engine or is it now on the rear like the 250?

Thanks to all for all of the other info.....has been very useful.
 
The current 200 220 and 250 diesels are all basically the same rear timing chain OM651 engine in different states of tune. The 200 has a single turbo inlet the 220 twin sequential turbos and the 250 the same but in a slightly higher state of tune [ more boost slightly bigger injectors??]Initially the 200 retained the old solenoid injectors while the 220 and 250 had the the dreaded piezo injectors-----around 2012 they all became solenoid injected with many 220,250's being retrofitted under warranty with solenoid injectors complete withnew ECU wiring loom and fuel return pipes.

http://www.emercedesbenz.com/Oct08/...The_Mercedes_Benz_Plant_In_Unterturkheim.html

http://www.mbclub.co.uk/forums/engine/77050-blue-efficiency-injector-recall.html

The engine thing is further complicated when you consider the NEW A B and CLA models which share various lower capacity versions of the MERCEDES OM651 engine 1,781cc together with the RENAULT DERIVED K9K 846 / Mercedes designation OM 607 DE 15 LA 110 hp BADGED as A/B/CLA 180 CDI. Ironically this "OM607 " engine shortly to be found in the base level W205 C CLASS has a toothed belt valve gear drive at the front of the engine and has received favourable reviews from the motoring press.

http://en.wikipedia.org/wiki/Renault_K-Type_engine
 
Last edited:
Steer clear we gave had some serious failures in our fleet with the chain stretch issue at relatively low mileage

Separate topic but the A class 1.5 diesels are giving some worrying issues too

Sent from my iPhone using MBClub UK
 
Steer clear we gave had some serious failures in our fleet with the chain stretch issue at relatively low mileage

Separate topic but the A class 1.5 diesels are giving some worrying issues too

Sent from my iPhone using MBClub UK

Would be interested to hear about the problems with the Renault derived 1.5 Diesels--- any links?
 
grober said:
Would be interested to hear about the problems with the Renault derived 1.5 Diesels--- any links?

No just reports from the fleet manager they are thinking of taking everything below the 212 off the car list as compared to the other german marques in the fleet the failure/breakdown rate is just too high

Will try and get some further info for you next week

Sent from my iPhone using MBClub UK
 
Interesting re the Renault 1,5DCi engine, as its normally a great little engine in Renaults and Nissans
 
No just reports from the fleet manager they are thinking of taking everything below the 212 off the car list as compared to the other german marques in the fleet the failure/breakdown rate is just too high

Will try and get some further info for you next week

Do they not lease the cars, if so, why worry, just get a replacement car.

The only info I have on OM651 engines is water pumps and fuel pumps leaking in air causing slow starting.
Simplex timing chains seems to be ok as they don't drive heavy load items, just the camshafts.

It looks a lot easier to change than most. Cam cover off, split chain, attach new to old, wind in, join ends together, cam cover back on. The tensioner looks a bit awkward to get to...


765945_1397254_2560_3580_41._OM651.jpg
 
Last edited:
Terry, do you ever see any injector issues now?...reference the horrendous 220/250cdi BlueE issues MB-Delphi had at W212 launch...

Is this well and truly now fixed? I seem to remember the injectors being replaced with Bosch parts...

Mercedes BlueEfficiency (OM651) - Injector Problems

I think it's scaremongering
The first one I looked after was a 59 plate with well over 200k on it still ran very well.
I personally have seen no chain issues but apparently they are common????
I must look after at least 40 of these engines well over 100k without any issues, so that must say something about them?
Yep I've replaced sump pans and valve covers, but only due to breakage.
To be fair you are getting lucky with any modern day Diesel engine at around 250k
 
Last edited:
The failed Delphi injectors are a specific supplier issue, they do not reflect on the engine's design or reliability.

Though I can see how this can give the engine a bad name in people's minds.
 
The new injectors are all the solenoid type still made by Delphi AFAIK. Initially claiming the problem was caused by "scaling up production" teething difficulties there were several "iterations" of the piezo injectors accompanied at each stage by "problem solved claims" Finally Mercedes bit the bullet and went back to the older solenoid type injector. As far as I know these are much more reliable and the failure rate is comparable to those on the older engines - however they all wear out eventually- but as Mercedes found to its cost some designs wear out faster than others!
 
Last edited:
I remember their was a massive storm at the time in Germany, when W212 launched and started breaking down at high incidence rates, causing really bad PR...initially MB blamed the supplier Delphi...and they in-turn blamed MB design....instead of all parties focusing on fixing the issue....the rest as below like you said (back to older injector design).

The new injectors are all the solenoid type still made by Delphi AFAIK. Initially claiming the problem was caused by "scaling up production" teething difficulties there were several "iterations" of the piezo injectors accompanied at each stage by "problem solved claims" Finally Mercedes bit the bullet and went back to the older solenoid type injector. As far as I know these are much more reliable and the failure rate is comparable to those on the older engines - however they all wear out eventually- but as Mercedes found to its cost some designs wear out faster than others!
 

Users who are viewing this thread

Back
Top Bottom