Old clonk/clunk - New trial

[harrytr5]

I can not remember if I posted this out so apologises if I have. Lever arm shocks do and can come loose resulting in a clonk. I always fit 2" longer bolts and nyloc nuts which secures it for good. Just a thought.

Regards Harry

[Casar66]

The clunk is at the front, Harry. 

I have swapt from the lever dampers to Konis many years ago.

[JohnC]

16 hours ago, Casar66 said:

How can I find the flex?

I never found it, only deduced it. I fitted the stub axle spacer kit from Revington and the clonk disappeared, never to return. So I concluded that the clonk must have been flex in the stub axle(s).

Given all you've done so far, maybe it's worth fitting the spacer kit or stronger stub axles.

Cheers,
JC

[Casar66]

Well, at least it is just another attempt after so many I did already.

But I'm actually against this intervention in the original design. 

I will have a look at Revington.

 

Btw: I have bought a new stub axle last year. Maybe it makes sense to try that first? Perhaps the old one become weaker   with the years?

Edited June 30, 2025 by Casar66

[JohnC]

On 6/30/2025 at 4:09 PM, Casar66 said:

Perhaps the old one become weaker   with the years?

I’d only be speculating. I would think that it’s unlikely to weaken except from cracks forming. And you would know about that pretty quickly, not in a good way. But if you have a new one, you may as well give it a try.

JC

[Casar66]

Today I installed the spacer kit. Guess what, the cracking noise still remains.
It pisses me off so much!

[jerrytr5]

Have you already checked the inner lower wishbone mounts? There is a strengthening kit which most 6's will have fitted as standard (I think 5's were retrofitted). However even with this fitted a crack can develop between the mounting holes causing it to flex and make a similar noise. You can only see this with the wishbone unbolted as the nuts/washers obscure the area.

Jerry

[Casar66]

Yes, I have checked that. 

 

The noise only occurs when I stop from a very slow speed. 
In the meantime, just as often in reverse as forwards.

Otherwise never! Not when starting off sharply or braking, not under full load when cornering. Never. Only when I stop (not during emergency braking from high speed).

 

which might be worth noting:

I already thought several times that the clunk was gone. This was the case a few times when the car was jacked up. Then it took a few miles or kilometers before it was back again. So there were always moments when I couldn't provoke the clunk. But once it's there, it keeps coming back.

Edited July 14, 2025 by Casar66

[Kiwifrog]

If it was me at this point I would strip the front suspension down completely and check everything, the spring seats, the silent blocks the chassis for cracks or damage the trunions all the suspension arms for damage, the suspension arm bushes, all the welds on the suspension mounting points etc if all ok I would then reassemble and do my best to ignore the clunk!

[Casar66]

Yes, you are right. Apart from the spring I did the most already.  I have hoped (for many month now) that I could avoid this. I am afraid after doing that the clonk will stay. And then I'll be suicidal or insane.

[harlequin]

It sounds as if you have been extremely through in trying to track down your clunk but just as a thought have you looked behind the baffle plates behind the front wheels, the plates that close the void between inner and outer wings, maybe there is somthing like an old radio antenna or a spanner that has been forgotten about in there?

George 

[Casar66]

No, I haven't. What is that baffle-plate and where to find it?  would you please show me with a foto or an illustration from the catalogs of Moss or Rimmer?

Many thanks

Cas

[harlequin]

Here you go. It's the plate with the rubber seal around the edge and the drain pipe passing through it.

The photo is copied from Ed Hollingsworth's excellent Bulfire website. (I hope you don't mind Ed)

George 

[Casar66]

Thank you!

 

I have never noticed that the panel is not welded to the body. Is it riveted?

[harlequin]

No not rivets its held inplace by the bolts you can see in Ed's photo, going from memory I believe they have a self tapping type thread that screws into thackeray  washers.

I remove the baffles every few years or so to squirt waxoyl in the voids. The plates are available in stainless if you find yours are tatty 

George 

[roy53]

Not sure if you have tried but Shock absorbers

easy to disconnect and try

Roy

[stuart]

32 minutes ago, harlequin said:

No not rivets its held inplace by the bolts you can see in Ed's photo, going from memory I believe they have a self tapping type thread that screws into thackeray  washers.

I remove the baffles every few years or so to squirt waxoyl in the voids. The plates are available in stainless if you find yours are tatty 

George 

No theyre bolted into captives welded on the outer edge of the kick panel, 1/4" UNF nuts.

Stuart.

[harlequin]

6 minutes ago, stuart said:

No theyre bolted into captives welded on the outer edge of the kick panel, 1/4" UNF nuts.

Stuart.

Thanks Stuart,

It's the old memory y'know

[Casar66]

2 hours ago, roy53 said:

Not sure if you have tried but Shock absorbers

easy to disconnect and try

Roy

I'm not sure what you mean by the shock absorbers?

 

1 hour ago, harlequin said:

Thanks Stuart,

It's the old memory y'know

 I will have a look tomorrow. I think, my ones are riveted by the former restoror 35 years ago.

Edited July 15, 2025 by Casar66

[harlequin]

58 minutes ago, Casar66 said:

 

 I will have a look tomorrow. I think, my ones are riveted by the former restoror 35 years ago.

Good luck, I hope you don't find any nastiness in there after 35 years

It may be worth fitting the plenum drain tube modification as shown in Ed's photo while you have the baffle plates off along with a good dose of waxoyl or similar 

G

[trchris]

Are you sure it’s suspension related? I traced a friend’s clonk to bonnet cones they had become rock hard over time 

Chris

[Casar66]

3 hours ago, harlequin said:

Good luck, I hope you don't find any nastiness in there after 35 years

It may be worth fitting the plenum drain tube modification as shown in Ed's photo while you have the baffle plates off along with a good dose of waxoyl or similar 

G

yes, I have the tube installed and a lot of "Mike Sander" grease inside.

[Casar66]

3 hours ago, trchris said:

Are you sure it’s suspension related? I traced a friend’s clonk to bonnet cones they had become rock hard over time 

Chris

No, I am not, but is my favorite source. The cones are ok and definitely out of the race.

[Steve-B]

Cesar, I know this may be a bit leftfield but I was under the bonnet today doing a check over, and discovered the bracket to the left of the radiator was loose. . Lightly giving it a whack it made a distinct clonk into the side of the rad, &/or LF wheel arch. Grabbed a couple 13mm wrenches and tighted it right up, no clonk anymore.

No doubt by now with the hundreds of hours you've been chasing it probably ain't your clonk, but thought I'd mention this.

Sometimes, its the simplest of things!

[harlequin]

41 minutes ago, Steve-B said:

 

Sometimes, its the simplest of things!

I once finally tracked down a persistent rattle to a tin of mints my wife had left in the door pocket

Don't give up you will get there eventually (or go completely mad🥴)

G