W164 AMG engine "ticking time bomb" (!!??)

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ab9758

Active Member
Joined
Mar 25, 2012
Messages
85
Location
Central London
Car
CL500 (W216) ex-ML500 ML63 AMG and ML55
Just had a buyer pull out of buying my 2007 ML63 AMG the night before collection. He's done a fair bit of research (I think first time buyer of AMGs) but had a very troubling conversation with someone from Mercedes (I think senior but unsure who or where from). Essence was that the AMG 6.3 engines from 2006-2008 were all high risk (quote: "The director said 'ticking time bomb'"). Issues related to "head bolt and oil leak issues with the engine range number of (your) car".

Apparently some earlier MOTs on my car had advisories about oil leaks several years ago, but there's been many full services by Mercedes since then. (It's always been serviced by Mercedes.)

Is there any reply I can give to the buyer? He's very genuine and I can't bamboozle or push him to take a risk. I've offered to have a Mercedes or equivalent pre-purchase engineering report done, but I think he needs more comfort over the generalised 'ticking bomb' issue.

Ancillary issue is that buyer then asked Warranty Direct about coverage in light of issue who have hesitated. (I'm not really worried about this as it was a Warranty Direct engineers who inspected my car before I bought it and I can get better warranty coverage elsewhere.)

My afterthought. If a bloody Mercedes director is bad-mouthing his own engines in spite of ten years of MB services, shouldn't he instead have been explaining how MB have cured this supposed problem????
 
The design of the head bolts didn't actually change until 2009/2010, so he is wrong on the first count!

The Mercedes specialists I have spoken to about this problem confirm that only a small number of cars were / have been affected by this problem. A warranty company shouldn't exclude a component unless there is evidence to suggest that the problem is a more common issue.

Most high performance cars have an 'Achilles Heel' somewhere in their mechanical configuration and there are usually aftermarket engineering solutions to rectify the problem IF the said part starts to give sign of failure. Increased coolant use is normally the first sign of this problem so offer to provide the prospective customer with the results of a coolant pressure test to help put their mind at ease.
 
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The 6208cc M156 engine is not a ticking time bomb, in fact it is virtually at the opposite end and "bomb-proof". Seriously, it's so well documented by now that these engines can be beaten on hard, yet they run strong always.

Your issue will be the headbolts which is again a well documented issue up until 2010/2011 but I'm not sure if like Mercy Me says, pre-2009 cars were ok. Most cars have had these replaced under warranty so if you don't know, check that yours have been. If not, for peace of mind then get them done or negotiate a discount with the buyer so that he may do, if they care even needs it done.

His "friend" really doesn't know what they're talking about.
 
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The 6208cc M156 engine is not a ticking time bomb, in fact it is virtually at the opposite end and "bomb-proof". Seriously, it's so well documented by now that these engines can be beaten on hard, yet they run strong always.

Your issue will be the headbolts which is again a well documented issue up until 2010/2011 but I'm not sure if like Mercy Me says, pre-2009 cars were ok. Most cars have had these replaced under warranty so if you don't know, check that yours have been. If not, for peace of mind then get them done or negotiate a discount with the buyer so that he may do, if they care even needs it done.

His "friend" really doesn't know what they're talking about.

Sorry if I did not make myself clear. What I meant to suggest was that the Mercedes Director got his facts wrong regarding the dates, so maybe cannot be relied upon when he states that it is a ticking time bomb! The new improved head bolts were fitted to this engine from around 2010 onwards so anything prior to that date did have the potentially problematic headbolts!
 
Hi. What a nightmare. I remember us talking a while ago and noticed your car on Ebay the other night. Looks clean / nice so am surprised you still have it.

Personally, I don't think there is much you can say to him to reassure him now unless you want to take £2K off the price for future head bolt replacements. I would imagine he's now heard many stories, and been told what the costs to replace are.

So, personally I would offer just offer him a review / report by a Mercedes dealer and go from there. The report can then be used on other potential buyers if this chap doesn't buy it. Also suggest he take a look at other cars to then appriecate what a good example yours is.

If he still isn't happy then he will need to pay another £6 to then buy a 2010 model. This is the point, for his budget he gets 2006 - 2008. If he wants to swerve the bolt;s issue then he will need to up his budget.

Simon
 
Well if he referred to it as a 6.3 engine, then he's instantly lost all credibility. ;)
 
My old ML63 w164 had 116k on it and run fine no problems, what is the milage on it?

The buyer can budget to do the bolts, there £168 the set, £50 each head gasket plus oil and coolant etc, rest is labour.
I have just rebuilt a 2012 engine with a bent rod at less than 30k on it so its the look of the draw with any engine.
 
I have a m156 car with over 100k miles the engine is perfect and silent on tickover.
 
Buyer has kept in touch and confirmed source of worry was Mercedes Coventry (who happened to be the ones who carried a full MB service 3,000 miles ago described on the invoice as "Major service with Plus Package Perform as of Code 809".)

No issues mentioned by them of "ticking time bomb".

There is a DVLA mention of oil leaks but referring only to the ML diesel models, not the ML63 petrol.

Anyway, current state of play is that prospective buyer has been in touch with extended warranty providers for quotes. I think he's focused on Warranty Direct who are infamous for wriggling at the last minute, whereas Motoreasy are normally easier to deal with.

He has however put them on the spot and this is where his dilemma has come about. I think (but unsure) he's raised the "ticking time bomb" issue with either or both warrantors and they have looked at earlier MOTs. Two have had advisories of oil leaks therefore he's fearful that it now becomes a pre-existing condition and won't be covered.

The leaks that were identified at the last MOT were in fact related to the power steering and all this has been remedied.

He's asked if I can show paperwork of oil leak fixed so he can show warrantors. Problem is that none of the service invoices identify this and there certainly isn't a leak at the moment. I think this takes me back to suggesting (strongly) that between us we get a warrantor's engineers inspection asap.

Had engineer check the car for me before I purchased and he reported:

"There appears to be an apparent oil leak when viewed from the front lower area of engine however not necessarily related to the engine, Engineer cannot verify exact area and recommends the engine area be cleaned and investigated fully then rectified if this is found to be the case."

Area was cleaned and confirmed to be power steering related and all pipes replaced.

Not sure how to overcome his hesitancy and I don't think it's a price reduction issue alone that would resolve this
 
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This won't be what you want to hear, but IMHO it seems unlikely this person will buy the car, and if s/he does then I fear they'll never enjoy it, as they're going to be paranoid driving it, which is a shame.

The M156 is a milestone engine, and it really shouldn't suit the character of an SUV but bizarrely it works really well. Whether they buy it or you own it for a little longer, enjoy the wonderful songs it sings whilst you can!
 
PS Have you tried Mercedes, will they put a Tier 1 or 2 warranty on it?
 
My old ML63 w164 had 116k on it and run fine no problems, what is the milage on it?

The buyer can budget to do the bolts, there £168 the set, £50 each head gasket plus oil and coolant etc, rest is labour.
I have just rebuilt a 2012 engine with a bent rod at less than 30k on it so its the look of the draw with any engine.

PS Have you tried Mercedes, will they put a Tier 1 or 2 warranty on it?

I think when I asked in passing Mercedes they quoted £4500 a year for coverage!

Funnily enough, yet again today I have heard from a mechanic I really respect who also wholeheartedly recommends the AA parts cover. I took it out for about £10 a month and it covers up to £500 a claim for five claims a year. Unfortunately, I've used up all my five lives as they insisted that the four ignition coils I replaced in two goes counted as two claims. They did though give me a brand new AGM battery fitted for the £35 excess and pay for the power steering repairs
 
I think when I asked in passing Mercedes they quoted £4500 a year for coverage!

Funnily enough, yet again today I have heard from a mechanic I really respect who also wholeheartedly recommends the AA parts cover. I took it out for about £10 a month and it covers up to £500 a claim for five claims a year. Unfortunately, I've used up all my five lives as they insisted that the four ignition coils I replaced in two goes counted as two claims. They did though give me a brand new AGM battery fitted for the £35 excess and pay for the power steering repairs

I thought it might be expensive, but that would give the best piece of mind. At £4,500 it's perhaps best to keep the money in your pocket though!

Maybe the coils would have cost more than the £500 limit so they separated into multiple claims to do you a favour? The stuff that this guy is worried about would cost much more to fix than the £500 limit, useful though it is for less expensive repairs as you've used it for.
 
How long has your car been for sale, and have you changed the asking price?
 
Buyers rarely say what they actually mean. If he's pulled out the night before collection it means he has cold feet. And you should have taken a deposit

Nick Froome
 
How long has your car been for sale, and have you changed the asking price?

I've had it on Auto Trader and ebay for most of the summer.

Reduced by £500 and expect it'll need to soften further.

May put it on eBay auction (instead of classified advert) but dreading whole process.
 

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