Brake caliper refurb

nophd08

Hi all, has any one rebuilt a brake caliper? I have a sticky front one on a caddy. Sticking on piston side, not slider. I might give it a go if I can get bits handy. I've seen on the net where piston is removed and cleaned and refitted using same seal. Probably better to source a new seal and piston. Any feedback? Thanks

Avns1s

It's probably the outer seal that is the problem, possibly unseated or torn allowing water etc into the piston causing corrosion.

I would suggest that the best option is to replace the caliper. A quick look on micksgarage has them at €130 assuming that I have guessed your model correctly.

You may do slightly better on an exchange unit from your local motor factors.

Hal1

Even if the seal only looks to be damaged all sorts of road dirt can get in there and score the bore. So I would exchange it too.

CJhaughey

I have rebuilt lots of them, the main cause IME is either corrosion on the piston itself which can be cleaned off with very fine wet and dry P1200 and rebuilt with the old seals.
Or the groove where the seals sit in starts to corrode and the reduced circumference causes the seals to grip the piston tight enough to cause it to stick.
In any case the method I use is to polish the piston until it has no protruding corrosion and to use a blowtorch to dry the caliper with no seals or rubber components left attached.
Once dry it can be cleaned and the dust and corrosion blown out with air or brake cleaner.
Rebuild with Red rubber grease behind the seals in the seal grooves and liberally smeared on the piston this will help prevent further corrosion.
Its actually remarkable how bad a piston can be corroded and still not leak brake fluid.
I have often run into a problem in a weekend where parts are not available and just had to do the best I could with old parts and never had a leak yet.

nophd08

Thanks for the reply's lads. My local motor factors will exchange for €100 but I'd rather strip and rebuild. If it goes pear shaped I can always exchange. I can't seem to locate a new piston and seal on the net si I'll reuse old one. Thanks again

Hal1

Bigg red sells refurb kits I used them a few times. Ebay shop: http://stores.ebay.com/Bigg-Red-Ltd

brembo26

Just make sure the rubber boot and the piston itself is in good shape otherwise you're wasting your time.

How do you plan on removing the piston from the caliper?

nophd08

brembo26 wrote: »

Just make sure the rubber boot and the piston itself is in good shape otherwise you're wasting your time.

How do you plan on removing the piston from the caliper?

Air compressor.

MercMad

I'd exchange it no question. I've rebuilt hundreds at this stage, but I wouldn't bother if I could get one for €100, and I wouldn't suggest this as a job for an amateur who hasn't done it before, no offence. Its not rocket science but its your life !!

nophd08

Caliper stripped, cleaned (small bit of corrosion around piston) with power brush and rebuilt with same seal. Bled brakes and left overnight with hard pressure on pedal. No leaks. Tested slowly around my own yard and worked perfect, hard braking included. CVRT passed on Wednesday, no problem whatsoever.