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How long do timing chains last?

I notice that the balance shaft kit (£300?) costs a lot more than the timing chain kit (£100), so how important is the balance shaft chain? (what can break, what needs to be replaced if it does?)
Also can the balance shafts be taken out instead, if it is a lot cheaper?


The upper guide on mine is worn, and the chain is a little niosy, probably no more than normal though. Its done 86k


How difficult is this to do? Im thinking about attempting it or getting it done, when the weather has gets better in feb/march.
 

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As far as I know if the balnce chain goes bad things happen. I am not sure though, because it is a known practice to remove the balance shaft chain completely. People say you gain some hp like this. As for timing chain, just wait till you start hear a rattling noise from the front of the engine. It means change your chain NOW. I am at 107000miles and still all quite. I heard some poeple change it at 60000miles or so. SO, it really depends, like with headgaskets: if maintained can run very long, if not, then will blow early.
If you know that your guides are worn, and chain is making the rattle noise, then chainge it.

THere is a lot of info here on forums on this subject, just do a search. It is a popular job on 9000s.

KLim
 

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What happens if your timing chain goes? And how much do you think it would cost to get it replaced by a mechanic? I don't know if mine really makes that much noise on it or not, but I don't know how long it's been on there. I assume it's been changed once alread due to the fact I have 194,300 miles on it.
 

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Don,t mix up servicing of timing chains with timing belts, belts snap & need regular 50 / 60k mile changes, chain,s last a long time and as said "talk" to you when they need changing, they can easily pass 150k miles but like all chains if they have stretched to the point of rattling then the pitch of the chain is now out of spec, so the teeth on the cam sprockets & the crank pulley will get worn to match the chain and therfore you have a choice

A) change chain before it stretches - say around 100K
B) change chain and sprockets when they get noisy - in this case if you only change the chain expect reduced chain life
what happens when it breaks, best look for a replacment engine, valves will hit pistons and bend, head can crack around valve guides, crank can get damaged etc.. but note it is very rare
 

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It also may be a good idea to change the chain guides for the timing chain and the balance shaft chain while you're (or your indie) in there.

And as Norman noted, the chain sprockets.
 

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This is what happens when the teeth shear off...lots of shavings in the sump over a 20000 mile period then terminal engine failure...

 

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Well, I was out at my car today, and I can definitely hear the timing chain makin' noise. I put my ear right up to it to listen and it's definitely there, no doubt about it. I bet it's going to be around a 200 dollar job if I make my estimations right. How long do I have to you guys reckon? I can hear it, but it's only a constant tick, nothing that sounds like it's going to rip through the block or anything.
 

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On my 86 300,000 km on the original chain and no signs of wear.


On my 97 210,000 km on the original chain and no signs of wear.

The timing chain should last as long as the engine unless the engine had lubrication problems at some point.

It is possible that you may need a new tensioner, these fit into the side of the timing chain cover and are not difficult to replace.

Some 91-93 2.3 engines had bad balance shaft gearsets which caused premature failure of the balance shaft chain, which is separate from the timing chain.
 
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