Hey guys:

Never use an aftermarket chain with a master link and clip rather than the MB type endless chain where you have to grind the ends off a set of pins to free a link, and must crip the pins on the new chain's removlable link. The clip will always fail, usually at speed.

Brian:

Get the stretch checked on your 420 at least every 30,000 miles. Quick and easy method on my previous post (set cam to TDC mark an look at balancer to see how "late" the crank is). Less than 8 degrees is OK, more means replace the chain.

Chains usually last nearly forever except in 420s, some 380s, and the 190 (early). My 220D has something in excess of 150,000 on it and no problems with the chain.....everything else is shot, but the chain is fine!

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

psfred, I am curious.....how does the M/B dealership roll in a new chain if it is 'endless'?

There is nothing wrong with a replacement chain that is of quality build. (read 'made in Germany')

For those contemplating this job, the official service manual from M/B on the V-8 engine, M116.96 (3.8) and M117.96 (5.0), states on page 05.7-320/1 F3, "A repair chain with connecting link is available for repairs. If only and endless timing chain is available, the chain can be opened prior to installation by grinding off both pins of a link and subsequent installation by means of a connecting link."

As I said, just get a good quality chain and you should be just fine. No need to get endless and fool with crimping.

You MUST crimp any replacement chain! Don't use a clip master link type chain. The clip master link is only good for temporary use while rolling in the new chain. DON'T USE THE CLIP MASTERLINK FOR THE CHAIN TO BE RUN!!!!!!!

I believe that just because a chain is "made in Germany" does not mean that it is necessarily a high quality chain. It's certainly a good indication. I am curious if there are any first hand experiences with breakage of ANY aftermarket, single row chain.

Have a great day,

While on this subject, how many hours of labor should it be to replace a timing chain, tensioner, and upper rails (specifically on a 190E 2.3 8v)?

Rags

The chain that broke has a mark on each link. The mark is:

JWIS

Is this an after market chain?

Looking at the broken link, doe the hole for the pin seem unusaully large?

Attached Thumbnails

 

__________________
Michael LaFleur

'05 E320 CDI - 86,000 miles
'86 300SDL - 360,000 miles
'85 300SD - 150,000 miles (sold)
'89 190D - 120,000 miles (sold)
'85 300SD - 317,000 miles (sold)
'98 ML320 - 270,000 miles (sold)
'75 300D - 170,000 miles (sold)
'83 Harley Davidson FLTC (Broken again) :-(
'61 Plymouth Valiant - 60k mikes
2004 Papillon (Oliver)
2005 Tzitzu (Griffon)
2009 Welsh Corgi (Buba)

Larry, who told you not to use a clip master link for repair? Also, which brand names made in Germany would you be leary of? (just curious, Larry)

Michael:

The links are made up of pins and plates with a spacer between the plates. The pins are held in place by being "riveted" -- that is to say the ends of the pins are expanded by swaging them with a swaging tool that drives a cone-shaped device into the end of the pin. Since the end is now larger than the hole in the plate, it stays put.

A master link type chain has one link with larger pins that have a slot cut in one end. A spring clip goes in the slot to hold the pins in place.

When you buy a new chain, it will have one plate with the pins swaged in on one side only. The other plate is free.

One then grinds or files the swaged end off of a pair of pins and uses the fancy Mercedes tool to push the pins and the attached plate off. This breaks the chain. One end of the new chain is attached to the old chain with the new pin set without the plate, and the engine is rotated by hand until the new chain is pulled all the way though and both ends are on top of the cam. Both parts of the chain, the part goin in and the part going out, must be kept in tension, and preferably in contact with the cam sproket to avoid jumping a tooth.

When the new chain is in, the pin set is put through the ends and the fancy Mercedes tool anvil is reversed to crimp (actually swage) the pins into place after the plate is installed.

Pretty neat, since you end up with an endless chain without a weak link.

The picture almost certainly shows a "master link" type chain, as the pins on the master link must be larger in diameter to have the same diameter as the other link where the slot in the pin is cut for the snap clip. This is why they break -- there isn't enough material around the larger hole. The snap clip can also break or get snapped off if the chain slaps, and with an oil pressure tesioner, the chain slaps every time you start the engine.

It also doesn't look anything at all as heavy as a typical MB chain.

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

There is no reason NOT to use a 'master link' on a replacement chain. The pins and holes are EXACTLY THE SAME as an 'endless' chain, and they ARE NOT a weak link. The clips do not vibrate off if properly installed. In nearly 50 years of working with and around equipment of all kinds with many roller chains, I have NEVER heard of or experienced a master link failure.

The chain that failed in this picture it would be most informative in the adjacent side plate was removed and the roller pin examined for wear. That is what failed on the broken link the roller pin pulled out of the inner side plate.

That kind of failure indicates the chain was severely overstressed (jammed by broken guide?) this assumed the hardness of the failed side plate was correct , which can be verified by hardness testing.

Fred, who told you the pins of the master link are larger in diameter? Why do you think the chain slaps everytime I start my little 380? (it doesn't)

Which 420 engine are we talking about here in regards to chain failure? Is it the 119? (Isn't there more than one?, I might be wrong.) Has anyone had a 119 timing chain fail? At what mileage?

__________________
Bob Johnston
03 E55
Comand/Nav/Bluetooth/Ipod added
Black/black
(Oh man, this car is sooooo fast.)

mplefleur,

I just got my replacement chain and I counted links. Once assembled it will includ 95 pins. The way I counted was two pins at a time and came up with 47 and an extra left ove meaning a completed chain would contain 95 pins. I hope this helps and keep us informed.

Everyone,

It's unbelievable that something like a timing chain turns into something controversial.

o I did not state that there was any aftermarket German made chain that was no good. On the contrary, I was ASKING if anyone knew of any aftermarket chain that was recommended or NOT recommended.

o To answer the attack about the clipped master link, this came from the Haynes manual and I have so far followed it with success. If you want to take issue, call the Haynes publishing company.

o I too, in my earlier years, raced motorcycles and never lost a clipped master link. However, there is availability of crimping tools and crimped master links are what is typically supplied. I have also heard pro techs here on mshop say to use the clipped type for rolling in a chain, not for regular service. Additionally a new MB does not come with a clipped master link installed. This all seemed to indicate that there is a valid reason, although I don't know what it is. I was merely trying to pass this information along.

You are free to put YOURS together with baling wire if you wish and I promise I won't say anything about it hence forth.

Have a great day,

Larry, I am sorry that you felt attacked? I merely asked your source of information. Wow! Or was it the difference of opinion that made you feel attacked? Dang! Woahhh, dude!

As for the haynes manual giving better information than the Merdedes Shop manual, I think I'll go with the advice and service procedure in the M/B manual. It states a master lind can be used. As far as the question about your suspect of German brands, you were the one that said because a chain comes from Germany does not necessarily make it a quality chain. Is it not logical that I would ask which brands from Germany you find suspect?

I appreciate the good information from all that replied to my original post. I do wish we had all discovered more on broken chains from those that have actually experienced it.

I would strongly urge making the timing chain an endless chain by using the correct tool to deform the pins on the master link - and not use a clip-type master link.

In another life, I am an American Honda factory trained Honda motorcycle technician (only honor graduate ever = 93 or better on all tests for the 8 classes taking 8 weeks to complete), shop foreman, technical advisor to American for the S. Texas region; after leaving became the supervisor of maintenence for the largest tree care company in the US (responsible for branch offices in Texas) and maintained everything from chainsaws to medium heavy-duty trucks - to name some of my experience in the area of mechnical/technical care of engines/vehicles.

Honda tech bulletins required changing timing chains for their overhead camshaft engines to endless chains from clip-type master link chains. This resulted in far fewer timing chain failures caused by the master link. Recall that many of these engines have redlines in the 8,000-10,000 and higher RPM range and that racing engines have tremendous forces exerted on them caused by redlines above 10,000 RPM.


Drive chains were endless and clip-type master links were not recommended - especially for the larger displacement engines (some may recall the early 750 inline 4 cylinder Honda motorcycles had many failures - many were caused by clip-type master links and sunsequently the change to endless chains).

Clip-type master links for timing chains can be used, but I would not. If you use a clip-type master link than ensure that the clip is completely in the grooves on the end of the pins and that the open end of the clip is facing away from the direction of rotation (if the open end is facing in the direction of rotation, then centrifugal forces will force the clip open and result in catastrohic failure). On racing motorcyles (especially road racing) the safety rules required endless drive chains (or safety wired master links which had smalll holes drilled in the master link clip and then high strength safety wire was threaded through and then secured by tightly twisting the ends together usually using a special tool to twist the wire - the safety wire we used came from the aircraft industry). On dirt bikes we used to safety wire the clip-type master link to the outer plate (obviously we were using very fine high strength stainless steel safety wire that did not interfere with the chain to sprocket teeth contact) and prefered to use endless chains or drilled pin safety wired master links.

I have the MB manual (1991 Ed.) for the 615, 616, and 617.912 engines (covering the 220D 1968-1973, 240D 1974-1977, and 300D 1975-1981). This manual shows a clip-type master link of the e-type clip, one clip used on each pin of the master link. The e-type clip is called that because it looks like a very rounded letter "E" when held up and orientated like you would write the letter "E." My previous discussion has been about the larger clip-type master link that engages grooves in both pins at the same timeand provides a much larger contact area on the side plate and, hence, is much stronger than the e-type clips. The e-type clips have a much smaller contact area on the master link side plate and, hence, provide far less strength. Also, the etype clip does rotate, the open end will eventually face the direction of engine rotation, and centrifugal foces can cause the clip to fail. My MB manual shows the e-type clip and these clips look like they have the much smaller contact area on the side plate that I am writing about (page no. 05.4-320/3) and this type of clip will rotate. I cannot agree with the MB manual in the use of clip-type master links, especially the e-type clip. Also, MB requires/recommends using an endless chain when doing an overhaul - should you use anything less when just replacing the timing chain? I think not.

If you have the e-type master link, then I STRONGLY urge you to NOT use them. I strongly urge you to not use the larger master link clip either.

To provide the maximum protection against timing chain failure, I recommend using an endless chain. The bit of extra effort to make an endless chain to avoid costly failure and spending 1,000's of $ to repair your engine.

You can rent a timing chain crimping tool from Performance Products for about $35 plus S&H for a two week rental. PP also sells timing chains that like many of their other parts have a 24 month transferable warranty - an unheard of warranty and shows the confidence PP has in the parts it sells. I have one of their timing chains on my 300D made into an endless chain using their tools and it works like the original. PP provides installation instructions for the timing chain and info on how to use the chain crimping tool. If you decide to make your chain an endless one using the PP tool, then I can provide other info to help you use the tool.

Hope this helps.

Tom

tcane, that resume is very impressive. I wonder how the education of the german engineers that wrote the service manual that states the use of a master link is permissable would stack up to your education?

Southern Son,

Does the MB manual mean a CRIMPED master link or a CLIP master link? A crimped master link still qualifies and may be referred to as a master link. They may mean using a master link is okay so that the chain can be fed in. They may not mean it is okay to use a clipped master link. If they do, I would be interested to know.

I apologize for claiming that I was attacked. Things have been very tense for me for a while and the REAL attack in New York has not helped my attitude any. If I was overbearing in my original post in which I warned against a clipped master link, I was only trying to help. I apologize if my tone was incorrect while giving that recommendation. The consequences of a failed chain in one of these engines involves several thousand dollars damage plus a good bit of frustration. BTW I WILL continue to use CRIMPED master links in my engines, and everyone is totally free to use what they wish in their engines. It's a free country.


PS I read the end of Mr. Cane's post about the E clips. I hope no one expects that the long C type clip will substitute for this.


Have a great day,