Mercedes List

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Mercedes List:
Mercedes even has a note in the parts look
up that says to see a technical bulletin about the single chain, and a says
under the MBUSA Note: "MUST NO LONGER BE INSTALLED!!!!", and it does have 4
exclamation points. The date of the note is 2/14/1991. It is a pure shame,
almost criminal, that Mercedes did not just do a recall and change all of
those!

>Are you saying "about 100%" meaning that a single timing chain 380SL engine
>that is well maintained lasting to 200k to 300k miles?

WHOA BOY! NO! There should NOT be any single chain cars by now. If you have
one, DO NOT START THE ENGINE before changing to a duplex chain. Period.

Bill Ditmire
Ditmire Motorworks,Inc.
425 White Horse Pike
Absecon,NJ 08201
http://www.ditmire.com
609-641-3392

>Sounds like Mercedes is saying this concern about 'single row timing chain" is
>all hype. I wonder if the 'data' on these engines will support their stance and
>that is the reason I requested data to support their position that the single
>timing chain is not as big a concern as many feel.

Mercedes has made hundreds if not thousands of different models of
cars and engines. A complete list can be foudn at the bottom of ths
post.

Here is a complete list of all MB motors that use single row
timing chains:

M180 230 (W114)
M180 230.6 (W114)
M123 250 (W123)
M102 up to 1988 (W123,W124,W201except 2.3-16 version.)
M103 300E/CE/TE (W124)
M116 380SE/SEL/SEL Only early crap US version.
1968 W114 250
M180 230 and 230S (W111 65-68)

If they're so good why did they use them so very very infrequently?

Mercedes is the only place you'll hear they're ok. The rest of the world
just giggles and snickers at the idea.

Dude, give the fuck up already. Everybody and his brother has
assured you these things are ticking time bombs and have been
known to break in as few as 30K miles. Do you really care what
the statistical average is, or MTBF might be for your car? Just
get the damn thing fixed already and be done with it.

The only people you seem to believe are ones that have a vested interest
in your engine failing, have you considered that?
Have you googled "mercedes single row timing chain" ?

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-----Original Message-----
From: Richard J. Sexton [mailto:richard@killi.net]
Sent: Friday, April 30, 2004 8:15 PM
To: todd@mbz.org
Subject: 380 chain

Mr. Knutson;
I read with interest this opinion on Usenet:

"This morning I stoped at an independent Mercedes repair shop. The guy I talked
with was in his 50's and said he has spent his entire life working on Mercedes
and knows SL's in and out. He claims he is well known in the area for his
Mercedes repair expertise and he seems quite knowledgable. He said that the
380SL is the worst of the 107 group because of the engine being underpowered.
He said that since I bought my 380SL new, did regular service, changed oil
often, and did not abuse it that the single timing chain might not be that that
big an issue. He said he thinks that perhaps those who let the oil get too low
or did not change oil often enough is the reason for the failure. Mine does not
leak oil nor burn oil - just not driven enough. He said he has repaired many
engines when the timing chain failed and his costs were $1700-$2000 to convert
to dual timing chain and $300 to convert the AC to R134 freon. Course, he did
say that it might cost $6k if the chain failed to rebuild the engine.

It would be interesting to obtain 'data' as hard numbers on how these chains
hold up so one can predict with probabilities of potential failure."

I was wondering if yoru group would like to comment on the accuracy of
these statements.

-----------------------
Mr Sexton,

Please pass this on, if you will:

First off, here is a pretty good article on the subject:

http://fly.hiwaay.net/~gbf/107/rt.html

I've played with 107 cars for 13 years. I've seen many early US market
380's succumb to the single row timing chain failure. I've also seen a
number of those cars survive because the timing chain and top rails were
swapped out every 50-60 K miles. The 40K reference in the article is a
bit conservative, but not overly so. It's relatively cheap to just
replace the chain. To the best of my knowledge, MB has stopped
supplying that chain, but there are plenty of alternatives.

To conclude: A conversion is not necessary if the chain is replaced at
50K intervals or less. The cost of a single row chain replacement is
10% of a conversion to a double row, so it's doubtful that there would
be any economic benefit for making the conversion. It's important to
replace the rails, as they can cause as much damage when they get old
and brittle as a snapped or slipped chain.

Todd Knutson

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Richard, thanks for the post. Regarding this issue, it appears we have the following:

- Doug Rugg says that at one time Mercedes did convert some of the early 380SLs, free of charge, to double row chain for some customers.

- Todd Knutson thinks a conversion is not necessary if the chain is replaced at 50K intervals or less.

- My local independent Mercedes mechanic concurs with Todd Knutson.

- But we have other experts whose opinion is that it is necessary to do a conversion to dual timing chain ASAP.

- Another post states that Mercedes MBUSA Note in its Technical Bulletin that the single timing chain "MUST NO LONGER BE INSTALLED!!!!"

- Mercedes no longer will supply the single timing chain.

- Still we have 1981-1983 380SL engine failures due to timing chain failures.

>> I don't think I mentioned that the chain that snapped at 27,000 miles
>> made no noise. There was no warning, nothing, nadda, the chain
>> just snapped.
>>
>> Stu

> "Data" like that is what I am looking for. Too bad Mercedes did not keep some
> sort of database that perhaps one can draw conclusions from. That 380SL that
> you mentioned snapped at 27,000 miles, do you think that it was driven hard?
> Could lack of maintenance (oil changes) have been a contributing factor?
> Perhaps just a fluke?

> CW

The car was maintained by the book with 3,000 mile oil changes.
Sprockets were updated. Rails were fresh. It was never driven hard.
Driving it hard shouldn't matter though. At that point in the single
chain debacle I was replacing chains every 30,000 as was recommended
by folks at MB. We thought with 30,000 we should have no problem.
Well, we had a problem. The chain literally tore apart. It was not a
pretty picture.

Stu

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>> My 380SL engine makes a "swishing" sound more so than a slapping sound.
>> After it warms up, the sound goes away. Would this more likely to be something
>> like a water pump rather than the chain?
>>

> I won't guess at sounds, but, it is not the chain. Chain noise is a distinct
> slapping sound.
>
> I don't think I mentioned that the chain that snapped at 27,000 miles
> made no noise. There was no warning, nothing, nadda, the chain
> just snapped.
>
> Stu

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www.mercedesshop.com/shopforum/showthread.php3?s=2136c97694efd3e0f

Don, I'm not really sure where you came up with a figure of less than $1000 to do the double row timing chain coversion.
This is a 107 SL, which means to do the conversion you either have to pull the engine and set it on stands, or drop the front suspension and subframe of the car and work from underneath.
To take the timing chest off, you have to remove the oil pan.
A SL has a one piece oil pan, so there are NO short cuts.
This is a job where you want to use MB parts only.
List on the MB parts is right at $1000. Pro MB labor is $100 per hour for the most part, and book time for this job is 26 to 27 hours for a pro. That's how I came up with $3500 for the conversion.

You *could* just replace the single chain and sprockets for around $1000. In my humble opinion this is a HUGE mistake.
I think it is absolutely necessary to convert the single row timing chain on the 380 engine to a double row. Single rows can snap without warning at any time. Even new chains and sprockets will fail catastrophically and suddenly.
On Sedans, you can leave the engine in place to do the conversion, but it will still run around $2500.
If you hear chain rattle on cold start up, TOW the car to a shop for the conversion so as to save an engine rebuild.

A good DIYer, with knowledge, skills and pro type tools could probably do this conversion in around 40 to 50 hours. But time constraints aside, it's one of those jobs best left to a pro.

There were rumors that MB did a brief factory unannounced recall
on the early 380's if the customer complained about the single row. It's said that MB did SOME of these conversions at no cost, under warranty. Why would they do this if the single row was sufficient? Needless to say, this practice was discontinued after a short amount of time. ($$$$)

Regards, Blitzen Bob

I've been told if you don't replace the timing chain on the 380 its pretty much certain engine failure on the early models. -- KirkVining

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My Gosh, this is a highly controversial topic!!! As we say in the software world, is there a "Best Practice"????