siegrisd

Hi, everyone.

I'm looking at a 2007 CLS63 (I saw previous posts in the W219 section that suggested that I post over here, too) with 84k on it in the Denver area. It's in superb shape cosmetically and drives very, very well. Being new to the M156, I do have a couple of questions about it. I have an ML500 with the M113 in it and have close to 200k on it. The M113 has been utterly flawless and is very quiet and very, very smooth even at cold startup. When I started up this CLS from cold this morning, it was noisier and more rough-running than I expected. It has excellent power and once warmed up, it smoothed out nicely. Is this normal?

In the Carfax, I was surprised to see that this car has been to the dealer several times relatively early in its history for major engine work. The first indication of oddness was at about 23k with new valve cover gaskets - no big deal. Then at 30k was back again, for lifters and cams. Then again, for head gaskets and then it indicated that piston(s) (YIKES!!!) were replaced. Then at 43k the lower end was redone and the rings were done.

Um... this seems like a LOT to do on an engine that has as good a reputation as the M156 seems to. The flywheel has been replaced at about 56k as well. Here's the VIN, if it helps.

WDDDJ77X87A099431

I'd honestly be all over this car, but, the early history of major work does have me a little spooked. Let me know what you think.

Thank you all for your help.

Rehabguy

Lemme open by saying that I am no expert when it comes to these cars. Having read the forums for a bit here and there I learned that the M156 suffered from a head bolt issue. If you do some research you will find that there are dates during which these cars were built that were definitely affected (I don't remember said dates). However, all that aside, given this specific vehicle's history, I wouldn't touch this with a 10' pole. One thing is a used car that suffered a minor fender bender, fine, so long as it wasn't T-boned or something. Another is a car that had pistons replaced, unless this was done as an upgrade by well known tuning house... hell no!

hyperion667

Oh boy, might be a good idea to pass on this one, sounds like a lot has gone on with the car since 07. I'm sure something will come around eventually

BlownV8

This is the first time I've ever heard the M156 had a good reputation - quite the contrary.

PeterUbers

PeterUbers

kponti

Or maybe all the problems got fixed now so it's better than the others listed online? (Half full glass alternative);

siegrisd

It's only $18,500 and has a fairly unique interior (Designo, maybe??) that I really like. Totally understand where you're coming from.

siegrisd

That's my thought too. Maybe Rolf (somethingsomething that I can't read on the plaque) had something else on his mind while he was putting this engine together and all of his missteps have been sussed out by this time. I like half-full glasses, but, I want to make sure they're not rose-colored ones, too.

siegrisd

I'm starting to fan out further than my local area in my search, but, I'm also in no hurry. Mmm... low $20s would be nice, but, I don't want to be too cheap/unrealistic. It seems like people are scared off by Mercs that are older, but, I'm not. I've had a number of them and driven them to high-mileage and have self-maintained/self-repaired them with very little drama. I like depreciation.

cetialpha5

So what's your take on the head bolt issue? That seems to affect a lot of cars. Comes up a lot more in the C63 forums. Basically a potentially ticking time bomb as it ruins the engine unless you replace the bolts in advance. Amg engines aren't as cheap as regular engines.

siegrisd

Since this engine has already been apart, the original head bolts have already been replaced. What I don't know, is if these replacements will have the same issue as the originals. What I might do is proactively replace them myself, but, I haven't looked into what that job really looks like. Some heads you can replace the bolts on one-at-a-time without removing the cams and such whereas others have to have the cams and their bearings removed in order to gain proper access to all of the head bolts. Clearly, research is needed here.

I'm going to look at the car again, and check for signs of oil in water and vice versa as well as I'm going to scan for any latent or stored codes.

cetialpha5

I guess it depends when the head bolts were done. Newer parts came out in 2011 so if it were done some time after that, then it may have the new part. There's a big debate over in the C63 forums as to the one bolt at a time method is good or not. That seems to work though as many have done it that way.

PeterUbers

siegrisd

Thanks for that heads-up. I'll head over there and will check it out.