993 sqweeky brakes!!!

[davidcross]

The brakes are new and razor sharp but there is a terribly sqweek when coming to a halt. This normal till the brakes bed in??

 

[davidcross]

They are driving me mad!!!

 

[clyde]

They probably don't have the damping plates fitted David. These clip into each piston and are glued onto the back of the pads, effectively eliminating the vibration that causes the squeel. I, like many others, don't bother with these as they making changing the pads a bit more of a hassle. Apart from a bit of squeel very occaisionally when braking at slow speeds I don't really get any noise from them.

It may be that it'll clear once they have bedded in but I would suspect not. You could try removing the pads and putting a bit of copper grease on the rear face. Or you may be able to take them out, fit the damping plates to the pistons and slide the pads back in but I would think that would be a bit tricky as the glue on the plates is really quite strong. If you really want the damping plates your best bet is to take the callipers off to fit them.

 

[sue11sam]

old thin wood chisel is good for knocking off the old plates , whilst still installed in the calipers, but after pushing back the pistons[]

 

[clyde]

ORIGINAL: sue11sam

old thin wood chisel is good for knocking off the old plates , whilst still installed in the calipers, but after pushing back the pistons[]

You obviously graduated from the Jeremy Clarkson School of Motor Mechanics []

 

[clyde]

ORIGINAL: clyde

ORIGINAL: sue11sam

old thin wood chisel is good for knocking off the old plates , whilst still installed in the calipers, but after pushing back the pistons[]

You obviously graduated from the Jeremy Clarkson School of Motor Mechanics []

Thinking about though, I do remember that the first time I did the pads I seperated the plates from the pads using an old paint scraper, so I apologise for any hammer wielding inferance in my previous response [&o]

 

[sue11sam]

ORIGINAL: clyde

ORIGINAL: clyde

ORIGINAL: sue11sam

old thin wood chisel is good for knocking off the old plates , whilst still installed in the calipers, but after pushing back the pistons[]

You obviously graduated from the Jeremy Clarkson School of Motor Mechanics  []

Thinking about though, I do remember that the first time I did the pads I seperated the plates from the pads using an old paint scraper, so I apologise for any hammer wielding inferance in my previous response [&o]

Horses for courses , I am only surprised that my implement has not become Porsche special tool No XP47/3, backing plate remover and available from your local PC for a mere £127.50 [][]

 

[clyde]

ORIGINAL: sue11sam
I am only surprised that my implement has not become Porsche special tool No XP47/3, backing plate remover and available from your local PC for a mere £127.50 [][]

I believe it was for a time but was superceded by special tool No XP47/3a which looked suspiciously like a B&Q own brand paint scraper but with the letters B&Q scored out and the word Porsche written on it in crayon.

 

[sue11sam]

ORIGINAL: clyde

ORIGINAL: sue11sam
I am only surprised that my implement has not become Porsche special tool No XP47/3, backing plate remover and available from your local PC for a mere £127.50 [][]

I believe it was for a time but was superceded by special tool No XP47/3a which looked suspiciously like a B&Q own brand paint scraper but with the letters B&Q scored out and the word Porsche written on it in crayon.

He he []

 

[davidcross]

I can't be doing with messing about with pads myself so it'll have to go back to Paul Stephens team to put right. It's embarrassing all that noise!!'

 

[MrHappy]

Another possible cause for squealing brakes - my backing plates had corroded slightly (two different metals in contact) giving just enough clearance to cause vibration. Never had a squeak since they were replaced. []

 

[davidcross]

Was it a relatively cheap job?

 

[clyde]

ORIGINAL: MoC2S

Don't confuse anti squeal shims with caliper plates.

The shims sit between the pad backplate and the piston, and are supposed to stop the pads setting up a resonant vibration.

Caliper plates are stainless, bolt to the caliper, and provide a bearing surface for the pad to slide towards and away from the rotor as you brake and release. They can curl due to dissimilar metal corrosion and jam the pad, causing brake judder and inefficiency.

Check tech articles for more info.

cheers, Maurice [8D]

Sorry if I caused some confusion here. PET refers to them as "damping plates" rather than "anti squeal shims", that's why I called them that. Typical Teutonic approach to naming things - they're plate shaped and damp the vibrations between pad and the disc. [8|]

 

[davidcross]

An article I read y'day on brake squeel said to get the car up to circa 90 mph then without locking the wheels let the brakes have it hard a few times!!! I gave it a good go last nite and poodling back home all was quiet although that may just be short term.

 

[MrHappy]

ORIGINAL: MoC2S

No, Clyde, you were fine .. it was just the reference to backing plates and bi-metallic corrosion in another post that prompted my post, in case it was all getting confusing !

cheers, Maurice []

Yes, good point Maurice, I've rewritten my post, hopefully it's less confusing now! []

 

[Super_Marv]

Caliper plates are stainless, bolt to the caliper, and provide a bearing surface for the pad to slide towards and away from the rotor as you brake and release. They can curl due to dissimilar metal corrosion and jam the pad, causing brake judder and inefficiency.

Nice explanation, but there was no need to call a brake disc a 'rotor' [] []