Mercedes timing chain (use a split link?)

[MrTibbs]

Hi chaps.

I've got a timing chain for my 230E saloon (1985). I've been meaning to change it for a while - it rattles a little bit on startup for a couple of secs until the oil pressure builds.

I've seen on some of the American forums that people don't recommend using a joining link (ie they insist it should be peened with a megabucks tool, or a hammer and dolly, risking breaking a tooth off the cam sprocket). I think these concerns come mainly from the diesel engines that are more common in the US.

I've got a joining link that basically has pins with grooves in them where you put a kind of circlip that looks a bit like a curved letter E. These clips stop the link from separating.

Some people insist these links are only for rolling the new chain in, while others say you can use them as a permanent measure (the haynes etc manuals do generally make references to joining links suggesting they're OK).

Anyone have any views on this, or even better any experience?

Obviously I don't want to do 'preventative' maintenance that wrecks the engine, but then again, timing chains/belts seem to be viewed as being incredibly fragile on most forums.

Cheers,
Mike

[alfaSleep]

No Problemmo, M8!

Wherever there are two car persons you have three opinions.......... theirs & this other guy they read about(who knows more)...lol

I am an old Hillman IMP nutter.... and never had any qualms about 'threading' a new timing chain on - with 'split link'.

1>> Wrap lots of rag around the open engine 'bits', for keeping out grit/dirt.
2>> cable tie around the chain - to keep it on the cam sprocket when 'broken'
3>> Grind gently the two peened ends of an 'outer - plate' link, both on the outside of the chain as it sits ON THE SPROCKET.
4>> slide link out, connect new chain with split-link >> 'C' clip with the 'u' end at front >> as chain runs.
5>> hold chain on sprocket either side, cut cable tie off, and have a helper turn over the engine on a socket (plugs out) and the timing stays OK and the chain rolls all around [you must hold it tightly to the ON &OFF sprocket teeth!!], then remove split link >> connect both 'new chain' ends [as note4]

Job Done.

I, personally, don't think a ToothedBelt , cam belt, should be 'retightened' after any job involving its removal - always renew

alfaSleep

[mr rusty]

Chain link tools don't actually cost that much- for a bicycle sized chain they're less than a tenner, and for a motorcycle sized chain fleabay is full of 'em for around thirty quid so even if there's some reason you can't use a split link then it's not going to break the bank to use a tool. I can't see any problem with using a split link though.

[alabbasi]

In most cases the original chain will not have a removable link, but all new chains will have a timing chain master link that looks like this:



You can use this just fine and you don't need a special tool. Just grind off the link on the old chain, connect it to the new chain and roll it in.

What's of more importance is to replace the timing chain tensioner and guides. The guides on later cars are made of plastic and break which can cause the chain to jump and that is what kills the engine. If it's a double row chain, then it will rarely fail (single row chains can though).

[MrTibbs]

Thanks for the responses - the link I have is like the one in the photo (though my chain's a single row so it's a bit narrower). I've got the tensioner as well and will do that at the same time.

I thought people seemed to be a bit OTT saying the clips that hold the plate on the pins might rattle off, good to hear other people don't think it's much of an issue.

re the chain tools, I have one for a bicycle as I used to be a keen cyclist, but bike chains have grooves in the pins so they're pushed on while on this one the pins are pushed in then peened I think. I'm not sure about motorbike chains, but remember reading on a forum that the tools won't work on a Mercedes timing chain.

Think I'll use the joining link on the assumption it seems pretty sound.

Mike

[alabbasi]

Don't forget the guides, those are critical.

[Maaarrghk]

I've followed this one with interest to see what others think.

If you decide to go with the "fish plate" type link, just remember that the "fish" swims with the flow, ie the direction of chain travel.

This type of link is common on small/medium sized motorbike drive chains, although bigger bikes have used the peened type of joining link for twenty years or more.

Personally, I would go for the peened link and get one of the "universal" peening kits suggested - M&P do one for about £50.

I dimly recall reading that the "fish plate" type links were made of softer stuff that the other chain links, thus providing a weak link - if the chain broke, it would be at the split link. But this may only have applied to motorbike drive chains.

I guess this all boils down to one question - Are you certain that the "fish plate" style split link is man enough for the job? Is the one you are using of a spec' that is recomended for this type of use?

If the quality of the link is up to scratch, then I cannot see a problem and would be very interested if you would let us know how you go on, but I just couldn't help but sound a note of caution - if this is such a good idea, then why don't all the car and bike makers use them?

Remember that you will not have any kind of guarantee with this type of link if it lets go and wrecks your engine.

[alfaSleep]

...if this is such a good idea, then why don't all the car and bike makers use them?

I would ask the opinion of a 'Non franchised Garage'... who offer the client the £1500 'everything off' Franchised dealer option, OR the "we'll lash one on + Guides" for £180..... and see what they think of 'Split Links'? No Quibbles from me, for sure!!

No need to use a 'split-link' on an original build, factory engine... brand new chain is fitted where the opportunity/need is.

alfaSleep

[suffolkpete]

I've used a split link chain on a BL 'E' series engine. I think the crankshaft has to come out to fit a continuous chain on that model, so it was a no-brainer as far as I was concerned. I covered about 50,000 miles afterwards with no problems. I don't believe motorcycle chains are a fair comparison, as they have to transmit a lot more torque and can be subject to shock loadings.

[mr rusty]

if this is such a good idea, then why don't all the car and bike makers use them?

..............presumeably because it's cheaper to buy in timing chains already made to a set length, rather than pay someone either on the line or in the chain factory to faff about fitting a split link. Time is money, set length ready made chains can just be bunged on one after the other without anyone needing to look if the fishplate is the right way round. It cant be a load issue as timing chains don't really suffer much in the way of stress, not like a transmission chain would, the same job is done by what's virtually a rubber band on small belt drive engines.