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Discussion Starter #1
Had a great day out at Brooklands today but trying to leave there's an awful vibration/grinding when pulling away and also whilst on throttle. I've managed to nurse the car to Reading services with very gentle acceleration to get me onto the motorway and up to a safe motorway speed.

My feeling is it's driveshaft related (offside) as I can feel it under my feet in the foot well and hear it on rotation. Think I'll manage to get the car home. Any ideas?
 

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Personally I'd take it back to Ned after all the work he's just carried out. Does it get any worse when you put lock on?
 

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Discussion Starter #3
Personally I'd take it back to Ned after all the work he's just carried out. Does it get any worse when you put lock on?
I'm going to speak to him when they're open on Tuesday or earlier if he sees this and contacts me. Will message him on here and their Facebook though.

I don't think it can get any worse to be honest. I managed to get the car home but it doesn't feel safe to drive with such a heavy vibration and knocking. There did seem to be some vibration through corners but nothing like what it is pulling away or trying to use the throttle in forward gears. Its completely normal in reverse too
 

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Loose drive shaft?
 

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I'm going to speak to him when they're open on Tuesday or earlier if he sees this and contacts me. Will message him on here and their Facebook though.

I don't think it can get any worse to be honest. I managed to get the car home but it doesn't feel safe to drive with such a heavy vibration and knocking. There did seem to be some vibration through corners but nothing like what it is pulling away or trying to use the throttle in forward gears. Its completely normal in reverse too
Yes it needs to come back in so we can see what is happening, probably would have been best to have it recovered in from Brooklands rather than driving it back to Swindon

Thinking about it following our conversation I advise not to drive it any further

Ned
 

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All sorted :bowtie:

Powderflex engine mount we fitted failed, this is a new product we are doing and the inner sleeve was 2mm longer than we specified from Powerflex so allowed too much movement

Replaced and stock engine mounts are to be adjusted accordingly

The noise was the drive shaft touching the sub frame, no harm done and back out on the road

Ned
 

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All sorted :bowtie:

Powderflex engine mount we fitted failed, this is a new product we are doing and the inner sleeve was 2mm longer than we specified from Powerflex so allowed too much movement

Ned
Hi Ned,

is this the failed mount or another (new) one you are developing?
 

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That is the one, sorted now though

Ned
How essential is the nylock nut on the top in the pic on your shop? My car hasn't got one on, I guess it was a pre-production version as the top plate has been tapped instead. Is the nylock nut just to stop the bolt from vibrating loose over time?
 

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How essential is the nylock nut on the top in the pic on your shop? My car hasn't got one on, I guess it was a pre-production version as the top plate has been tapped instead. Is the nylock nut just to stop the bolt from vibrating loose over time?
Yes, the one on my car worked lose so I added the nylock. The top plate is threaded but the nylock locks it in place

Ned
 

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engine mount
All sorted :bowtie:

Powderflex engine mount we fitted failed, this is a new product we are doing and the inner sleeve was 2mm longer than we specified from Powerflex so allowed too much movement

Replaced and stock engine mounts are to be adjusted accordingly

The noise was the drive shaft touching the sub frame, no harm done and back out on the road

Ned
yes go me ......... lol
 

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Discussion Starter #15
All sorted :bowtie:

Powderflex engine mount we fitted failed, this is a new product we are doing and the inner sleeve was 2mm longer than we specified from Powerflex so allowed too much movement

Replaced and stock engine mounts are to be adjusted accordingly

The noise was the drive shaft touching the sub frame, no harm done and back out on the road

Ned
Just been out for a short drive and coming home I've got a very similar vibration as before although no where near as bad. Suspicion is that the modified Powerflex bush has failed, again.

Email waiting in Ned's inbox for Monday morning to try and get this sorted so it lasts longer than a week this time :lol:

Think Ned mentioned the original ones aren't available anymore otherwise I think I'd just go with a new one of those to be safe.
 

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Sorry to hear of your on-going problem, it's not always wise to experiment with crucial components, because sometimes Alfa knows best. And OEM is far cheaper, Birth more so!!
 

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Possibly, but I'm still confused as to why it's only doing it in forward gears. I would've thought a loose driveshaft would vibrate in reverse too.
Mine did this, turned out the top mount hadn't been tightened. Every time you drove forward there was a terrible racket due to the engine relaxing back and basically bouncing on the subframe.
Worth checking at least, only 2 No17 torque bolts.
 

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Sorry to hear of your on-going problem, it's not always wise to experiment with crucial components, because sometimes Alfa knows best. And OEM is far cheaper, Birth more so!!
Sadly this particular OEM rear mount is not what it was, they changed supplier about 2 years ago. The new ones last 12 months tops before they start sagging, and then the exhaust flexis and top engine stabiliser pick up the slack to their detriment. The Birth ones are the same. They can be identified by the white nylon inner where the old ones used to be black. Not sure what the issue with the Powerflex mount is in this case but for me it is the best long term solution.
 

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Discussion Starter #20
Sadly this particular OEM rear mount is not what it was, they changed supplier about 2 years ago. The new ones last 12 months tops before they start sagging, and then the exhaust flexis and top engine stabiliser pick up the slack to their detriment. The Birth ones are the same. They can be identified by the white nylon inner where the old ones used to be black. Not sure what the issue with the Powerflex mount is in this case but for me it is the best long term solution.
Dan, as Ned said previously, the inner sleeve of the bush was too long and allowed movement. It basically tore the bush apart. He shortened the sleeve on the replacement but it seems it's done the same again. My guess would be it either needs shortening further or a suitable washer to stop the movement. Unless there's an issue with the bush itself I can't think of any other obvious reason for repeat failure.

Both times the failure has occurred going from slight to full throttle, with the engine rocking back under load, putting the bush under peak loading. Will see what Ned thinks when we speak on Monday.
 
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