What are the early symptoms of the need for timing chain replacement? I have a warranty for another 10,000 miles, the car has 110,000 miles.
My tech says it has a little rattle upon starting, but that "they all do". I would really like this to be something the warranty pays for, so I will have to document the need.
I'm thinking of taking it to the dealer, telling them I suspect it needs a timing chain, and wait for them to say, "of course you do", something they are known for. I rthink my tech thinks too much in terms of saving customers' money.
Anyhow, any early symptoms? By the way, the warranty covers "normal wear and tear".

Tom
92 500E

I think a fluctuating Oil Pressure guage (at idle) may be a early sign, I remember gathering that from one of the post here.

The only sure way of knowing is to have a stretch measurement performed on the chain.

What is more important is to get in the engine and change out the Timing Chain Rails as they are plastic. These are the little guys that only last 100K on average and if the wrong one should break, the displaced piece could act as a wedge between the moving parts.

Ouch...

I wonder if it might be advisable to try to re-make the brittle, plastic rails in another (more durable) material... say... aluminum or - CARBON-FIBER...

?

(hi, Jim)

>I wonder if it might be advisable to try to re-make the brittle, plastic rails in another (more durable) material... say... aluminum or - CARBON-FIBER...

A couple of people have suggested this, and apparently at some point, an aftermarket vendor (?) was offering all-metal rails for the classic MB V8 engines.

Several engine guys said that this is probably a bad idea: a metal rail won't break, but the wear particles from it will be much harder on the lubricated internals than are plastic particles.

I confess to not being up on the durability of carbon fiber vis-a-vis abrasive wear, and will reserve comment about that.

What's really needed is a design where the rails are easier to access for routine replacement.

s/b

I just had mine done. My car had 146k on it (I've owned it for 10k miles and don't have a complete service history). I took it in to have the stretch measured. There was a decent amount of labor to do this. The stretch didn't turn out to be the problem - it was the plastic rails. There were visible breaks and actual pieces of broken rail stuck in the chain housing.

I had no advance warning, no strange sounds. However, I'm confident that had I not gotten this done, I was at risk of much more significant damage. I had the upper and lower rails done, as well as the chain, tensioners, etc. It was pricey.

how "pricey" was it, exactly?

: )

LOL...Scott...you too funny...CF rails.

But, not a bad idea if ya' think about it...
Wonder what went into the twin turbo Sauber M119 motor?...hard to believe they used the stock plastic pieces (though, they probably tore down the motor every weekend and replaced eveything like that)

I'm also curious to see what hanfrac's T-chain cost...its always neat to see the variances of prices over the country. Hope it wasn't astronomical.

__________________
Jim

1992 500E
2007 CLK63
2003 Audi RS6
2001 Audi allroad

Labor to inspect chain and replace chain, tensioner, upper and lower rails - $1950

Parts - another $600 or so

So I paid about $2600 in Las Vegas (I believe my shop's hourly rate is $72)

Not too bad...it'll be many years before you need to do that again....hopefully.

Not bad on the labor rate either...I know some of the West coast folks pay over $100 for an hours worth of labor.(ouch) My fav dealer is around $80 here in CT.

__________________
Jim

1992 500E
2007 CLK63
2003 Audi RS6
2001 Audi allroad

Though most California Mercedes-Benz dealers will be hard-pressed to quote hourly labor rates (ridiculous, IMHO), if one does the math, it equates to approximately $120/hour.

YIKES.

In Texas I paid ~$850 labor for the TChain Job a couple of years back on the 400E. I bought the parts from Caliber motors and and the entire job was ~$1500. The first thing I do is ask for an estimate of the Labor and get the labor rate before I have anything done. Most shops go by "the book" and from book to book (Chiltons VS. ALLDATA) there are sometimes fairly significant differences as far as what the "books" say the labor shld be. I believe the labor was 10-12hrs @ ~$70/hr. But as was pointed out, labor rates are certainly based on Geography. Like most things, rates seem to be cheaper in the Southern states LA,MS,AL,TN,AR,OK VS. Southeast,N.east, and Cally

__________________
Regards,

Albert
aldedmon@yahoo.com

Sweeeet Al...that's the lowest I've heard on a T-chain for a M119. Lucky you.

In CT...a shop, including dealer shops, HAVE to have a state supplied sign with their hourly rate posted in plain view...along with storage rates, diagnostics, towing, etc.

Though I'm not paying for my chain, which will get done in a month or two, I've been quoted around 2 grand from the dealer...even with the parts at wholesale ($460) it seems fair enough to me.

__________________
Jim

1992 500E
2007 CLK63
2003 Audi RS6
2001 Audi allroad

I did the lower rails at my shop's recommendation, even though the general consensus here is that they are not prone to fail. Had I not done the lower rails, I think the job would have been $300-500 less.

I had no discernable symptoms. However, with 147k on the clock and no records of this being done, I had them go in to measure the stretch. Just to have the measurement cost about $300 in labor. But once in, we saw big pieces of broken rail in one of the chain housings and lots of broken rail pieces in the oil pan.

So I, for one, am glad that I didn't wait for the symptoms, as it looks like I was pretty close to having a serious problem without adequate warning.

I've read somewhere that if there are no symptoms, not to even go in to measure the chain, that it is too intrusive.


Any feedback?

Tom