brake pads binding (citroen c3)

Hello again,

I was driving home from my MOT, I passed BTW, but I thought the steering felt stiffer than on my drive in. During the drive home I would have braked lightly several times. Once, about halfway home, I heard a squeal and thought a bit of grit had got in but the noise went and I heard nothing on the times I braked after that. I didn't do any heavy or emergency braking. When I did brake, the car didn't pull to the side or do anything untoward.

But when I got home, I could smell a brakey, burney, smell. I decided to take off the wheel for a closer look and that's when I had trouble with the security bolt which sheared off (see my other post). When I finally got the wheel off (with 3rd party help!) the disc looked fine: there were no scratches and no foreign objects were trapped. The pads had a lot of friction material left on them, so it's not that they had worn out. I had to drive to get the nut sorted and I had an uneventful drive to and from the dealer. So it's all a bit of a mystery what caused the smell. I'm sure the pads must have binded. Would that account for the stiffness?

The only thing that wasn't quite right is that there is a very thin metal plate clipped onto the back of each pad. There is a small metal clip on the top and on the bottom. On the one pad the top clip is loose, so this metal plate is not quite secure. The caliper comes in contact with this plate. Is it possible the plate was moving independently of the pad, and this caused the binding?

What should I do? Should I remove the plate and use the pad without it? I haven't seen these plates on any other make of pad I have fitted. What is it for? Can I manage without it?

Thanks. Stephen.

Reply to
Stephen
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you could leave the shim off if you like, it is there to reduce brake noise. But it would not cause brake binding. During the mot the brakes are applied harder than you ever would on the road. The cure for a binding brake is to dismantle until you discover what is stiff and then rectify it. Sometimes it is just a clean and lube, sometimes it means a new caliper, or anything in between.

Reply to
Mrcheerful

Thus spake Stephen ( snipped-for-privacy@nowhere.com.invalid) unto the assembled multitudes:

I had a nasty experience with a binding brake on my Astra on a drive down to Exeter in March this year. The car became unresponsive to the accelerator, and as I reached Honiton I noticed smoke rising from the front offside wheel! Strangely enough I had a similar experience, though much less severe, in almost the same place on exactly the same journey the year before. On the previous occasion I took the car to Kwik Fit in Exeter who replaced the pads.

On this second occasion I had to get the breakdown people out, and the car was taken to Kwik Fit in Exeter again where they replaced the whole caliper, hoses and pads (the pads replaced under warranty as they were less than a year old). It's been fine ever since. Strangely enough the nearside wheel still has the original calipers etc but has never given any trouble.

Only if it was preventing movement of the pad, i.e. holding it against the disk, which seems unlikely. The theory with my Astra's binding brake was that the hose may have been breaking down inside, the detaching lining creating a blockage and hydraulic lock. Whether or not that's plausible, I was just happy to have a working brake again.

My thoughts would be if the plate is there, it's there for a reason. If you can do without it then surely it wouldn't have been fitted in the first place.

Reply to
A.Clews

It'll be the anti squeal shim, so removing it might make the brakes squeal, but it won't stop them working , alas I'll bet it won't stop them binding either.

Reply to
Duncan Wood

That's what I thought it was but I wasn't sure. Is there any problem with it being slightly loose?

Is this likely to have caused them to bind?

and then rectify it

I have dismantled and couldn't see anything wrong but the brakes seemed to cure themselves. I managed to drive to the garage to have the wheel nut removed without any problems before I stripped them down and there was no binding en route.

Reply to
Stephen

It can do, sometimes the edges of the pads rust, (sometimes it is the ends of the pistons that are rusty) when the brakes are applied really hard the pad is pushed hard enough that it moves a tiny bit further than normal and the rust binds the pad (or pistons) in place giving a slightly seized brake, it could cure itself with vibration and cornering combined with heat from the binding. I would still want to give it a clean out and lube, or it will happen again and be more inconvenient. The shim being slightly loose will make no difference in practise, as long as it doesn't fall out.

Reply to
Mrcheerful

There was a little rust on the shim and piston, so perhaps that's what happened?

I have done this and nothing has happened since, so hopefully it has been cured.

Thanks for the reassurance. I don't think any of my other pads has had shims. How do they stop squealing?

Thanks

Reply to
Stephen

pads only squeal when there is movement and fretting giving vibration/noise, the shims can prevent or reduce that, as can some glue (as on some vehicles) so as long as there is no movement that can set up a squeal it does not matter if shims are there or not. Shims are a cheap bodge to fix an annoyance rather than an essential part.

Reply to
Mrcheerful

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