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MG MGB Technical - Pads crumbling

Has anyone experienced this before..........I haven't!
Just driven back home, 100 miles so. Pulling to one side, so investigated. Took the pads out (new discs and pads 6k ago) on the offending side, both pads have "crumbled", one almost gone completely the other 3-4mm left. The other pair of pads have a 6-7mm and are fine. The "crumbling" is just that, it looks like the end of a stale loaf!! Outer contact surface, middle gone. Disc looks ok. Neither piston seemed stuck, they both retracted easily.
Is it an over-heating problem, a composition problem or a disc casting fault or other???
Allan Reeling

I don't think 100 miles of mis-alignment would wear out a decent brake pad...Sounds like a material defect.
Check disc with a fixed wire pointer, mounted on a board.
Rotate wheel with pointer just off the disc, and see if it touches anywhere....Will show a warped disc...
It has to be defective pads, at least that's my 2 penny opinion.
Edward Wesson 52TD

agree with Edward, sounds like very dodgy product. Return them and complain in the strongest possible terms or report them to the trading standard on the grounds of accident prevention.
Name and shame the supplier and/or manufacturer?

best of.....
M McAndrew

Sounds like you have had a sticking caliper. BT, DT, smelt the pads, and they were badly crumbled (see pic). Although exercising the pistons in and out they seemed free enough, but I wasn't taking any chances so changed calipers, discs (as the offending one was blued) as well as pads. Shortly after that a pal had exactly the same problem so I did his as well.

PaulH Solihull

More or less the same Paul, except the middle had gone and left a rim! So probably overheating, my first suspicion, but when the piston didn't seem stuck I started doubting materials, which may seem silly, when the other side was perfect. BUT I couldn't find a manufacturers name on the backing. Maybe it's poor product yet again, being less heat tolerant if the piston is a bit slow at backing off.
Allan Reeling

Allen, replacement pads are usually marked with dot matrix printing. The problem is you can never find out what formulation the pad material is, generally only high performance pads with give you any useful information. With regards to sticky pistons with Lockheed calipers, the pistons need to be cleaned properly when replacing the pads otherwise the piston will tend to stick,I suppose you know all about that,a knackered flexi hose will give you a similar problem, it doesn't take too long with the pads binding the de-nature the pad material.
Hope this helps.
john wright

Thanks John,
New SS flexibles. Always clean pistons, but the seals go and lose their "nature" too. So guess the calliper is in need of a look-see. Stoneleigh this weekend!
Allan Reeling

This thread was discussed between 11/02/2013 and 12/02/2013

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