Brake Caliper Problem...Help Needed.

facktor,

Maybe there is a bit of grit jamming the seal slightly and not allowing the piston to fully retract. The angle and flex of the seal is what retracts the piston and if something is inhibiting that then that may be it. Only way to tell and then only maybe, is to dismantle the caliper and have a good look at the seal. Maybe have a new one on stanby anyway and just replace it. Other possibility is free play at the pedal, is pressure coming off? Is return spring fully returning the pedal?

Hope this helps
Steve

They're probably not hard to pull apart. I haven't done the brembos on the Berg yet, but I imagine that they are simple enough. just remove the disc and pump the pedal and the piston should pop. If you run low on fluid, top it up, or just pull the piston. There'll be a seal or two in there. Be careful, and be clean and lube with brake fluid when reassembling. You can get special assembly lubes for brakes too but not really necessary in my limited experience with rebuilding brakes.

Good luck
Steve

Its how I've done it on other disc brake systems.

faktor ...

get a rear caliper kit to suit , fresh brake fluid , a clean area to work in .

take note of whats in the caliper kit , and remove the same parts in the caliper .

i think you have become a victim of dirt , crap , and moisture , inside the brake system .

beware of trapped air when you attempt to bleed the system back to life !!!

faktor,
You should not have to crack the bleeder to displace fluid when you push the caliper piston back in.

This should automatically push back into the master cylinder reservoir when the caliper piston is depressed.Unless the m/cyl is too full and wont allow it

Not sure about the Brembo rears, but I have seen an adjustable lever fitted to a front brake once that was adjusted too much, allowing the m/cyl piston to go past a port in the m/cyl, effectively blocking the return of fluid..

This meant that all fluid was trapped between the m/cyl piston and caliper piston, and when the fluid heated up it had no room to expand other than push the caliper piston out and make the brakes drag, instead of returning back into the m/cyl when the lever was released...............

Also make sure you grease the 2 sliding pins under the dust covers when you have the caliper apart- have seen these seize up/get sticky due to corrosion too.

Just something else to keep in mind if the other fixes above dont get you out of trouble..

Hi faktor
Weird problem but the pads are obviously not returning for some reason. Ausberg could be onto something with the no expansion theory.
The Brembos are the same setup as any other brakes. They have a rubber seal around the piston.
Take it off, rip it apart and clean everything using aerosol brake cleaner and check bore and piston for any scoring/damage etc.
If it's not damaged and not leaking then lube it up with nice clean brake fluid and re-assemble. You shouldn't need a kit unless you damage something.
I find it easiest to remove piston with compressed air. If you use air place a rag in there to catch the piston when it comes firing out.
Totally re-bleed system and check if they release. Problem may be in master cylinder.
Good luck.
Coops

i'm guessing the brake pedal plunger that goes into the master cylinder is too far extended for some mechanical reason. does the caliper piston retract if you pull the plunger rod clip and remove it?

slacken the rear break leaver adjuster off its the round disc just abouve the break leaver arm with an off set allen screw it might have been knoked and is holding the rear break on