What's making that knocking noise?

Messages
28,216
#1
Opportunity?

Seriously, just got the GT back with new NS track rod end. Now goes in the direction the steering wheel goes, which is super :) I'd forgotten what it's really like.

But the original symptom remains and our (breifish) examination couldn't find fault with anything else (particularly bushes)

Full left lock and reverse gives you a clonk you can feel and sounds like it's coming from the OSF wheel. Also seems to match wheel rotation (which makes no sense to me at all*

Any thoughts

TIA

C

*This is not an unusual state of affairs but I suddenly wonder if there's a balance weight on the inside of the wheel fouling on something....
 
Messages
2,168
#6
Opportunity?

Seriously, just got the GT back with new NS track rod end. Now goes in the direction the steering wheel goes, which is super :) I'd forgotten what it's really like.

But the original symptom remains and our (breifish) examination couldn't find fault with anything else (particularly bushes)

Full left lock and reverse gives you a clonk you can feel and sounds like it's coming from the OSF wheel. Also seems to match wheel rotation (which makes no sense to me at all*

Any thoughts

TIA

C

*This is not an unusual state of affairs but I suddenly wonder if there's a balance weight on the inside of the wheel fouling on something....
Do you feel it through the steering or body? Is it the same on a smooth surface and a lumpier one?
 
Messages
28,216
#10
Do you feel it through the steering or body? Is it the same on a smooth surface and a lumpier one?
Body I think, although now you've asked I might have to check again. Seems to be worse on smooth (for example it doesn't do it when I reverse into the drive which (as you'll recall) is mostly gravel. The bushes though *did* clunk going into the drive. I wonder if it is just the wheel skipping a lot.

C
 
Messages
297
#11
I thought it was at first but I don't *think* so. I should probably find an empty carpark and reverse around it for a bit.

C
Much like Oliver, could it just be wheel slip/diff locking up

My Alfa used to do this, from the front only on full lock (low speed obviously!) - wrong driven wheels, but are you sure its coming through the front? anyway was really bad on one particular brand of tyre - to the extent that I thought Id smanglized the LSD. changed tyres and it went away - totally non existent with the current Kumho tyres unless its very cold and the ground is damp.
 
Messages
28,216
#12
Much like Oliver, could it just be wheel slip/diff locking up

My Alfa used to do this, from the front only on full lock (low speed obviously!) - wrong driven wheels, but are you sure its coming through the front? anyway was really bad on one particular brand of tyre - to the extent that I thought Id smanglized the LSD. changed tyres and it went away - totally non existent with the current Kumho tyres unless its very cold and the ground is damp.
Pretty sure it's the front, yes, but.....

Maybe I can see if if Mrs C drives it

Cheers
C
 
Messages
28,401
#16
Change of direction on lock is 9/10 roll bar bushes.

If it only does it after the cars been stood for a while and only on the first sharp turn then this is the diff and normal. Lack of lubrication as all the oil is in the bottom of the casing coupled with dry gears and put it under maximums stress, it’s is more of a whirring than a clock though.
 
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Messages
28,216
#18
Change of direction on lock is 9/10 roll bar bushes.

If it only does it after the cars been stood for a while and only on the first sharp turn then this is the diff and normal. Lack of lubrication as all the oil is in the bottom of the casing coupled with dry gears and put it under maximums stress, it’s is more of a whirring than a clock though.
Does it pretty repeatably, no matter if it's been standing.. How do you mean 'change of direction on lock', Matt? Pretty sure we checked the ARB when we were under there.

Cheers

C
 
Messages
28,216
#19
Well, after my saying it was consistently re-producible, I noticed that the Homebase car park was nice and empty. So I thought I'd re-produce it.
Could I ********. Neither direction. So I guess it was just a fluke of the surface when I pulled out of Feli's (ooooerr) or it is just tyre skip. Happy days.
C