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Discussion Starter · #1 ·
Morning all,

I had these changed on my '94 Aero this week, and opted for rubber replacements rather than poly. But, now it's been done the vibration in the car is horrendous - more like I would have expected with super-hard poly bushes. Is it possible that the torque arm has been refitted badly/wrongly? It looks OK to me.....

Chers,

Ben.
 

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Have both the bushes been fitted with the holes fore and aft? This allows some movement to be soaked up.

If they have been fitted with the holes to the sides then you will have a more solid connection with more transmitted vibration when the engine moves forward/backward.

Andrew
 

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It's hard to define the vibration, but I've just fitted a Superflex bush to the engine side and a standard bush on the bulkhead side of the torque arm.
The vibration was more, but it smoothed out a little bit over a week or so of driving. I also didnt look at where the holes are in the standard bush, but that would make sense - although I can't see it making a huge difference.
Have you had the other bushes checked? I wonder whether the solid top end might be showing weaknesses elsewhere?
 

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Discussion Starter · #4 ·
Thanks for the replys guys.

Just checked, and the holes in both bushes are indeed fore and aft.

As regards weaknesses elsewhere, would problems with the lower hydraulic mounts cause excess vibration? What about the gearbox mount which looks very similar to the torque arm bushes?

I'd have thought that if they were knackered and soft that they would probably soak up more vibration while allowing excess movement. Unless of course the old torque arm bushes were so far gone as to effectively disconnect the engine and its vibration from the rest of the car!

On another note, my rear ARB bushes look very similar to the ones in the second photo that BillJ shows here i.e. a pretty loose fit, and they move quite freely along the ARB. Question: is fitting a new tighter fitting bush all that is required, or do I also need to do something with the rubber coupling/bush that connects the top of the link to the rest of the suspension.

cheers,

Ben.
 

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Originally posted by BenH:
[qb]On another note, my rear ARB bushes look very similar to the ones in the second photo that BillJ shows  here i.e. a pretty loose fit, and they move quite freely along the ARB. Question: is fitting a new tighter fitting bush all that is required, or do I also need to do something with the rubber coupling/bush that connects the top of the link to the rest of the suspension.

cheers,

Ben. [/qb][/b]
Yes, it is worth using the poly bushes, I fitted them to mine a month or so ago & I was amazed at the difference - a good value upgrade. My old rubber ones where like those in Bill's photo. And, by the way, they are cheaper than the rubber ones.

Like you, I also noticed that there seemed to be some sideways play on the links where they connect to the chassis. They don't seemed to be mentioned anywhere in despatches. I guess they don't wear to any extent. There don't seem to be any replacements available either - I imagine the only option would be to replace the links complete.
 

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Discussion Starter · #6 ·
It's just been suggested to me that the excess vibration could indicate problems with the balance shaft sprockets/chain, and that the only way to tell is to remove the timing chain cover, and from what I've read elsewhere this (unless you're very very careful/lucky) will almost certainly require the head gasket to be done as well.

Any comments?

cheers.
 

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Just a thought but I had heavy vibration on hard accerlating. I had the lower mounts changed and it got a lot better, I had the two tops changed to superflex and a abbott poly gearbox mount and all vibration gone..

I think the point is, is that they are all quite dependant on each other so it would be worth checking the bottoms too..

Just my thoughts..

HTH
 

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Discussion Starter · #8 ·
Thanks for your thoughts, but my problem manifests itself in almost the opposite fashion to yours. In my case the vibration is very obvious at idle, and much less so once the revs rise above about 1500.

I ordered the rear poly ARB bushes yesterday afternoon, and they arrived this morning before 8am! (Thanks Elkparts!) I'll be fitting them sometime today, so since the jack will be out I'll have a look at the other engine mounts anyway and see what condition they're in.

If memory serves me correctly the engine wants to rotate forwards under load, so maybe the rear lower mount is shot, allowing transmission of excess vibration at idle, but when it rotates forwards under load it is less apparent.

Clutching at straws I know, but I'd rather pay £ for a new mount rather than £££ for balance shaft chains/sprockets!
 

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It's actually the other way. The top of the engine moves backwards under load, so compressing the rear lower mount and tugging at the front one. It is the tugging that really does the damage so it is more usual for the front mount to fail first. Once this happens, the rear mount often fails shortly afterwards.
 

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Discussion Starter · #10 ·
Thanks BillJ, after I'd written that last post I went and checked and thought, "******, I'm wrong, I hope everyone's doing something else today so I can sneak back and edit my post before anyone notices!". Ah well, never mind.


It's funny, but the vibration is far more apparent in the car than in/under the engine bay. Maybe time to book it in to see the doctor.

Well, the ARB bushes are done, although one of the bolts was determind not to let go. Anyway, 'tis done, and blimey, what a difference!!!


cheers,

Ben.
 
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