M157 & M276 Camchain Tensioner - Heads Up

[st13phil]

Soon after purchasing my E63 I noticed that on start up there was a noticeable rattle from the top end of the engine for a few seconds. This would persist longest if started from stone cold, but was also present if started after the car had been idle for a few hours. It wasn't instantly noticeable from within the cabin, but was obvious if stood outside the vehicle.

A quick Google search turned up a relevant XENTRY document, published 16 June 2013, which had been posted on one of the USA forums.

Bottom line is that the issue is caused by the secondary timing chains rattling until sufficient oil pressure is built up in their tensioner systems. The fix is to install revised secondary timing chain tensioners and check-valves in their oil supply passages. This work has now been carried out under warranty on my car and it has resolved the problem.

Form the XENTRY document, M157 engines prior to 157 9xx 60 022333 (December 2012), M2768 engines prior to 276 8xx 30 001281 and M2769 engines prior to 276 9xx 30 406603 (February 2013) are affected.

 

[Deleted member 65149]

Thanks Phil. I noticed the same noise on my M276 engine - nowhere near as bad as a diesel, but not nice. I went back to my dealer when the car was just a few weeks old but they said there was nothing wrong. I'll be visiting them again now to get it resolved.

Do you have a link to the XENTRY document? I haven't been able to find it yet.

 

[Scott_F]

Shouldn't such an obvious problem have been picked up during the engines' design and development process involving vast amounts of time, money and engineering expertise ?

 

[st13phil]

In defence of your dealer, I doubt that it was a recognised fault when your car was just a few weeks old, but it is now.

As it's bad form to post links to documents on other forums, just Google for "m157 rattle on start". It's the pdf at the top of the results list

 

[st13phil]

Shouldn't such an obvious problem have been picked up during the engines' design and development process involving vast amounts of time, money and engineering expertise ?

This is not a defence of MB, but from what I can deduce not all examples exhibit the problem. Also, many deficiencies come to light only after designs are put into general service, so the answer from me is "maybe".

 

[Deleted member 65149]

Thanks Phil. I'll take the Xentry doc to my dealer and see what they say. The rattle isn't as bad as this one, but still a bit disappointing for a V6 petrol engine.

[YOUTUBE]3Ce90rss3n8[/YOUTUBE]

 

[Bryan Allman]

Mine showed similar symptoms and having downloaded the XENTRY document and confirmed my engine number sat square in the middle of the range, I took the car to Purslows (my local main dealer) who booked it in and completed the mods as detailed in the document quibble free - all at no charge They also upgraded the Comand maps etc at the same time. Big thanks to Purslows for great customer service and even bigger thanks to the forum for yet more valuable advice

 

[MOR8A]

I'm getting no joy on this via dealer or MB UK, they are saying that my car is not affected. Thoughts or advice chaps please.

Anyone have the Xentry document?

 

[sjmaxwell]

I'm getting no joy on this via dealer or MB UK, they are saying that my car is not affected. Thoughts or advice chaps please.

Anyone have the Xentry document?

Try this link;

http://www.google.co.uk/url?sa=t&rc...wkrAeb4aYIfViihjdkngCQ&bvm=bv.118353311,d.d2s

 

[tasosmos2]

MB E63 (M157) timing chain marks

Hi to everyone,

I want to share one video regarding the timing chain of M157/M278 engine.

https://youtu.be/_2ML1ErrJt0

I hope that i will help someone!
Actually it's easy ☺

 

[Jukie]

I know I'm resurrecting an old thread but I thought it preferable to starting a new one.

The Xentry document refers to M157 engines "From engine number 157 9xx 60 009368 up to......".

What might that mean for engines with numbers before 157 9xx 60 009368? Might it infer there isn't a problem?

 

[Jukie]

Also, can anyone give me an indication of how much it costs to rectify the rattle?

TIA.

 

[st13phil]

What might that mean for engines with numbers before 157 9xx 60 009368?

Are there any (installed in the W/S212) prior to that engine number? (honest question - I don't know).

Also, can anyone give me an indication of how much it costs to rectify the rattle?

ISTR someone of this parish, perhaps Jules (@Cyclone1) had the work done at their cost and may be able to share that info. From memory, when the dealer did my pre-facelift car under warranty they said it was more than a day's work, so the labour is going to be substantial.

 

[Jukie]

Are there any (installed in the W/S212) prior to that engine number? (honest question - I don't know).

For info, I have my eye on a pre-facelift bi-turbo, registered in March 2012, that has an engine number ending 92??. The current owner says as far as he knows it hasn't been done and there is a noise on startup

 

[Deleted member 65149]

My M276 engine is one of the listed rogues and I was initially concerned about it. Whilst it was under warranty I got it checked out at the dealership where I bought it but was told that it wasn’t bad enough to necessitate the revision (AKA they didn’t want to do it). Six years later and I still haven’t had it done, but it’s not so noticeable now. Whether it’s “eased off” or I’ve got used to it, I don’t know.

 

[Abb]

Am sure I have read on here somewhere it is an engine out job on the M157 and is circa £3-4k! Like @st13phil states, @Cyclone1 one may be able to clarify, as I know he had his done!

 

[AMGeed]

For info, I have my eye on a pre-facelift bi-turbo, registered in March 2012, that has an engine number ending 92??. The current owner says as far as he knows it hasn't been done and there is a noise on startup

If there is the likelihood of the chain tensioners needing replacing, I'd give that particular car a miss given the possible cost to you.
Unless you are an ace at negotiating and can get £3k or so off the asking price

 

[Jukie]

If there is the likelihood of the chain tensioners needing replacing, I'd give that particular car a miss given the possible cost to you.
Unless you are an ace at negotiating and can get £3k or so off the asking price

One can but try but I don't hold out much hope!

 

[daveenty]

Mine was with Mercedes back in 2017 to have the chain tensioners and non-return valves sorted. I had to pay a contribution of £280 which I didn't think was too bad considering that it was over 4 years old and heavily modified. I think that this worked out around 30% at the time though I'm not over sure now.

They had it for four days in the end though I think that the time period was down to their inability to understand the instructions, a complicated carbon fibre air intake (which they managed to damage), and also realising that both sides were necessary.

The engine does not need to be removed, there's plenty of space to get to everything and it should take less than a day to complete on a standard car.

 

[Cyclone1]

Depends on the year of the car what needs doing. If an early 2011-12 car never had any work done by the dealer related to the cam timing chain rattle early in its life, then it’ll likely need the timing chains replaced and all associated sprockets, tensioners, guides etc. Parts and labour is over £3k, then you have to factor in any other parts that may need replacing if perished or worth doing whilst the engine is out. For me it was around £4K all in. When I bought my car (2011 December model), I knew that at some point in my ownership that this job may need doing and that’s how it turned out. It’s an engine dropped out job for proper access and ease of turn around.

There are a few cars outside the range on the X-Entry that have needed work, but most of these should have been fitted with the check valves and tensioners when new so may not have always needed new chains, although some did receive the newer designed chain (late 2016 I think this became available), to be sure the issue is less likely to return.

For the OP, then if the car you are looking at definitely hasn’t had the chains done, then I would recommend factoring this into the price you pay, or look at alternative examples. You could get lucky and the engine may never need the work done, but in time i think that is less likely.