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Discussion Starter · #1 ·
A while ago, my car developed a mid range vibration. The local dealer diagnosed a tired front engine mount. Changing this made things better, but not perfect (the old mount showed no signs of failure). Over the last couple of months, it has got steadily worse. The dealer now commented on a tired gearbox mount, which I do not disagree with. When running the engine however, the immediate and definite conclusion was that the balancer shaft chain has jumped a tooth. I was wondering about this previously, and thought that perhaps it had jumped one tooth before, and now two, or possibly both shafts have jumped.

Has anyone else experienced this? I'm a little concerned as I have not heard of or read about this problem before.

What's the best source for the chains and related parts if this really is the problem? (Original parts obviously)
 

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How old is the car, Mark, and with which engine? The early B234 (2.3) engine was known to have problems with the hardening on the balance shaft sprockets and it's not uncommon to see sprockets from this vintage with the teeth almost worn down to nothing. In this condition, it wouldn't be difficult for the chain to slip. If this is the case, eventually the chain will come off altogether and foul in the timing chain. You can imagine the expensive chaos that would follow...
 

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Ah... balance shafts... let me tell you a little story...

My 93 2.3 suddenly developed quite a bad vibration at about 1500 rpm, regardless of whether or not it was in gear. I thought "uh oh, balance shafts"

Off to the garage; they concurred so it was out with the lump and a full rebuild. One dead balance shaft (seized bearing IIRC).

Back in with the overhauled lump, problem still there, though not as bad. Out again, strip down, found other balance shaft dicky (luckily I wasn't paying for this bit!!).

Back in, everything checked and double checked, and problem better but not gone. Frustration all round.

After a lot of searching it was eventually traced to a broken spring lever in the clutch, causing it to run unblanced. New clutch, and everything sweet as a nut

So, whilst balance shafts are a possibility, there are other things that may not be so obvious...
 

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Originally posted by saabz2000:
[qb]Get fixed quick! [/qb][/b]
Well, if it turns out to be a late-model B204 or the like, with about 50K miles on it, then chances are very slim that the sprockets are badly worn, so let's not panic yet.
 

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Discussion Starter · #7 ·
Sorry for not including the obvious info:

1994 2.3litre FPT (B234L I think)
automatic
94,500 miles

I have rented a Ford Ka (oh bliss, but it was the only thing available in Marlow on a Saturday) for a week so that investigations can begin as soon as possible.
 

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Discussion Starter · #9 ·
I maintain a heathly scepticism as there have been no signs of chain related rattling. To be able to jump teeth I would have expected either the chain to have worn beyond the tensioner limit and therefore rattle, or as you suggest, the teeth to be virtually non existant.

However, there's not much we can do except to take the chain cover off and see if the shaft(s) has indeed become a "non balancer" shaft.

By that stage of course, I've committed enough money to almost make it worth changing the chains etc anyway, given the mileage.

Why is life never straightforward?
 

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Discussion Starter · #10 ·
Well, having been given completely conflicting advice by some of our well known specialists, I have replaced the gearbox mounting. The vibrations are now about 90% reduced, and the remaining 10% may, or may not, be my imagination.

The conflicting advice was, Source 1: absolutely definitely the balancer shaft chain, Source 2: definitely can't be the balancer shaft chain if it doesn't rattle at idle.

I'll just carry on and see if it's cured, or whether it deteriorates further. Unless of course anyone has any suggestions.....

Thanks for the help.
 

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New member DaveJ here again.
I previously posted regarding a timing chain rattle having been told that the job would cost €1200 by the dealer.

For some reason the damn thing has gone back to almost whisper quiet. Is the tensioner back in place or is it the calm before the storm for my wallet? Car is 95 9000CD 2.0lpt auto and is otherwise sweetas. There is a minor coolant leak and will have to get the head done at some stage (about .5l every 500miles).

Any suggenstions?
 

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Originally posted by DaveJ:
[qb]New member DaveJ here again.
I previously posted regarding a timing chain rattle having been told that the job would cost €1200 by the dealer.

For some reason the damn thing has gone back to almost whisper quiet. Is the tensioner back in place or is it the calm before the storm for my wallet? Car is 95 9000CD 2.0lpt auto and is otherwise sweetas. There is a minor coolant leak and will have to get the head done at some stage (about .5l every 500miles).

Any suggenstions? [/qb][/b]
Not long after I first got my '92CS the chain rattled a couple of cold mornings, but soon stopped. It hasn't done it since, I've just changed the oil regularly and put it down to poor oil quality at the time. I've still got the chain and tensioner in my toolbox at work.

As for the coolant leak, are you sure it's the head? Half a litre every 500miles is not that much, so I'd make sure it was the head before paying out for the head gasket.

Neil
 

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There is a minor coolant leak and will have to get the head done at some stage (about .5l every 500miles).  [/b]
Have you checked ALL the hoses? I had minor coolant lost which turned into a large coolant loss (1 header tank full every couple of days) this turned out to be loose/missing pipe clips on the coolant hoses on the BACK of the engine (under the inlet manifold/injectors). My local garage fixed it and I've not lost a drop since (3K+ miles and coolant level is still smack in the middle of the header tank).

They did say that the hose is very hard to get to from on top and they put it on a ramp and went in that way.

Steve
 

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Discussion Starter · #15 ·
Thought I'd resurrect this post to tell you all the good news! Apologies for posting this twice, but I'd forgotten that I'd started two threads on this topic.

My car got worse again, so whilst I was off ski(v)ing last week, the car was dissembled to find the following:

The sprocket on the exhaust side balancer shaft was so worn that the chain would simply slide over a large section off it. Two teeth have broken off (what little was left of them!!), and the others vary from being almost non existant to being about half their original size. Whether the shaft was still turning, or whether the chain was just slipping over the worst section was not clear. There was also some minor corrosion on the head.

So I now have:

1) New chains, sprockets, guides, tensioners etc
2) A skimmed head
3) New plastic tensioner pulley for the poly vee belt
4) A lighter wallet

So I have more or less a new car, and it's back to full turbo nutter mode.

Hurray!
 

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Sorry, I must have missed your question at the time, Harvey. I'm afraid I don't know when the problem was resolved.

However, here are some photos of Mark's sprockets. You can see why the chain jumped when you compare the relatively unworn teeth of the inlet shaft sprocket with the almost non-existent teeth on the exhaust sprocket




 
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