Brake caliper problem

[kiesta00]

Today I was changing my brake pads and tried taking apart my calipers for some work, but they're stuck to the mounting bracket. The sliding rods with the dust boots are frozen...how the hell can I pull them apart? My pistons are also stuck, which causes my brakes to drag all the time. I tried using air to pop them out, but they just won't budge. Any help would be appreciated.

[matt250r21]

Heat and carefuly beat. Use a propane torch and a lot of luck.

[deathman53]

its not easy, I rebuilt 3 rear calipers and all of them had frozen pins, I drilled a hole, heated them up some, put the caliper in a vise and used a nail punch to hit the pins out, 2 of them the metal sleeve came out too, so more heat and press the sleeve back in. Drill a small hole, heat them up, drip in penetrating oil, let them sit, then hit the pins out, when done, put some jb weld on the holes and that should do it, it sounds alot easier than it is though.
As for the frozed pistons, put a c-clamp on the brake pad and put a c-clamp on the other pad, but far enough out so you can grap the piston, when those pistons are far enough out, remove the c-clamp from the other and do the same. Both calipers should have the pistons far enough out so you can grab them with pliers and pull them out the rest of the way. Again, sounds easier than it really can be. Be prepared for some really fun filled shop time!!!!!!!!!!!

also make sure you have new rubber seals, o-rings, and caliper boots, as the old ones probably won't be any good after the heating of the caliper.

[DezSled]

The best is to regrease the floating pins regularly before they become frozen. But...

I have had to rebuild calipers before. Use liquid wrench inside the rubber boots before hand to help loosen up the frozen pins, let them sit for awhile. Heat up the caliper w/ a propane barbeque or a toaster oven. Only to 200-250 degrees. Put the caliper in a vice to secure it. Twist, pull, yank on the pins till they come out. Drill out the back side of the caliper as a last resort, using a small diameter punch to help persuade them out. Use liquid wrench, or any non-flammable chemical to help remove them. WD40 is flammable. Seal hole w/ jb weld, silicone or what everyou choose.
Heat the caliper for the piston removal also. Set up the master cylinder w/ hose primed with fluid to push out the pistons. Use the vice to hold the caliper in place. After heating pump up the master cyl to get the pistons moving, if only one moves use a c clamp to stop it from coming all the way out. The piston w/ the parking brake pin on the back side is easy to get out, its the other one that is tricky if it doesn;t move. Push the parking brake piston in to help make the other piston to move, use brake fluid to help lube it. If it doesn't I've had to drill a hole in the face of the piston to get a small bolt in to help pull the piston out. The idea is to save the pistons as they are the most expensive part of a rebuild.. Take your time. Use Makays brake caliper assembly lube when rebuilding (auto parts store). Refer to the break down in the service manual for the small oring that goes on the parking brake piston. I would not recommend using the piston seals/dust seal/oring again upon rebuilding. good luck

[kiesta00]

wow haha, sounds fun. My friends tell me to leave the front brakes off since i'm making it a drag bike, but you never know when you'll need good brakes lol. I guess i'll slave on those brakes tomorrow afternoon, thanks