Strange noise

[snes]

My 86 Gtl seems to have developed a strange noise on the passenger side. When the car hits a depression type bump (pothole, dip etc) I can hear a strange knocking type sound. Hard to describe, but imagine a knocking exhaust pipe - that sort of thing.
Jacked that side of the car up, checked and tightened exhaust hangers, checked torsion bars for looseness, visually inspected front wheel nuts for tightness. All seems good.
Only work I have done recently is replaced cv boot on drivers side and caliper pistons on other side. Dont think there is a connection.
Sound is heard when front and back wheel hit dip - never noticed it before. Any (polite!) suggestions?
Thanks!

 

[claude van rouge]

I had a clunk from the front turned out to be this: http://www.renault4.co.uk/forum/showthread.php?t=1927

 

[malcolm]

Dampers might be a possibility. Do you also have a lot of wheel vibration at about 65mph?

Does the knock seem to be coming from the front or the back, or in the middle?

 

[snes]

Think I've found it. Its the caliper carrier. I can actually move it a few mm by hand. Its the side where I replaced the caliper pistons. Yet all nuts were torqued up to correct setting. It is the caliper that is clunking when I hit a dip or bump. I know there is usually some movement in disc brake units, but this seems excessive. I'll take the wheel off tomorrow for a closer look.
Any advice on this?

 

[snes]

Well, I've inspected the front assembly - everything is bolted and secure, but the caliper carrier can be wobbled easily by hand a few mm, and shakes audibly when on the move. But the brakes work, nothing looks likely to fall off anytime soon and the new caliper pins which seem to be the cause of this slight movement are those currently recommended as correct by Renault.

I suspect Steve knows his disc brakes inside out - any comments or advice on this Steve? Or any one else?

And if I cant remove the slight play, can I damp the caliper slightly to eliminate the noise?

 

[Steve Hennessey]

The caliper is supposed to be loose and it's unlikely to be making a knocking noise. Remove the nearside shock absorber and test it. Is the rubber buffer positioned correctly on the torsion bar? Have you checked to see whether the engine and gearbox mountings are ok?
Can you replicate the noise by bouncing the front when stationary?

You will find the noise eventually by process of elimination!!!

 

[snes]

I did strip down the front assembly as Steve suggested - but everything checked out except the disc caliper carrier, which was audibly and visually loose. Secure, bolted, but loose.
So I removed Mr Renaults expensively new caliper pins and compared them with Mr Girlings cruddy originals - and found virtually 2mm difference in diameter. No danger of sticking there!
So I cleaned up and replaced the originals, now much more snug.
Quick question - apart from making an irritating noise, would there be problems having the caliper carrier so loose?