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Discussion Starter · #1 ·
Hi, all.

Seeking a consensus before I go and see super-Del on Saturday for a prognosis.

- Rear offside brake started grinding, metal-on-metal sound about a month ago. The sound doesn't lessen while I'm braking, and it comes and goes - making noise 70% of time. Rear discs are very worn anyway.

- Pad seems not to be making contact with the disc on the visible, exterior side, as the whole disc looks rusty. However, in MOT last week, the guy said it was braking better than the other wheel and the handbrake was releasing ok. Car doesn't pull to either side when braking.

So, is the caliper seized on the outside only, and braking on the inside of the disc is ok? Would the whole caliper need replacing, or as my Dad says, can we get the rubber o-rings replaced for cheap? Is the MOT guy right in saying the problem's just that the discs are so worn and the pads have hardened?

Answers on a postcard, pls!

I may take the wheel off on Friday to check pad wear and see if the calipers are moving ok, and listen to where the abrasion is.
 

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The calipers only have one piston.. pressure applied to the other side by the caliper "floating" on slides.

As your pad isn't working on the outside edge, it is obvious the slides are causing the problem. Depending on how bad they are, you may be able to remove them, and clean/grease and restore normal working order..

The metal on metal sound is probably just your pads worn down to the metal.. not good for the disks.. and depending on how badly scored they are, and thickness wise, you may have to replace these as well.

John
 

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Discussion Starter · #3 ·
Ok, thanks.

From reading threads, it seems that re-greasing them only lasts a matter of weeks before needing to replace the caliper anyway - or have I got it wrong?

Is it as simple as it sounds - buy grease, put onto sliders an drive on, or do I need to do a bigger dismantling job?
 

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should last a year or two at least..

and yes, it's that simple..


John
 

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Discussion Starter · #5 ·
Ok, thanks, final dumb question - any old grease, or what do I ask for at Halford's?
 

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Copaslip, or any brand of copper based high melting point grease..

Use it on the backs and edges of the pads as well.


John
 

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Discussion Starter · #7 ·
Update

Had a look last night.

Pin came out fine, caliper will only open as far as 65% of piston clearing fixed part of caliper.

Pulled back rubber flange on bottom hinge, used copper grease to help remove rust, then cleaned up and sprayed well with WD-40 while moving it. Still won't move much more.

So, just managed to get existing pads and clips out. Inside pad was worn down to the metal and then some, outside pad ok.

Couldn't get clips back in (2am), so replaced outside pad and another part-worn one for the inside. Had to remove whole caliper assembly to do this and only use a pad with less friction material than my other spares otherwise it wouldn't have fitted over the disc.

Reassembled, tested, to notice fluid leaking. Though I'd damaged the pipe where it meets caliper and was surprised to see no jubilee or other clips over it, but checked orther side of car and remembered that these screw on.

On further investigation, found that I'd knocked the banjo bolt loose while trying to get the caliper to swing open. Tightened it, bled this brake, all seems ok for now, apart from slightly rattly clipless pads!
 
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