calliper pistons won't budge
 

Hi,
Had a little incident at the track...ran out of pad material.
Brakes faded a little, then no brakes.

Anyway pulled the pads out which were just warped metal backings:eek:
Noticed the inner pistons were pretty hard to compress, outer ones easy.
Cracked the nipple on the inside....still did not budge, and I was really leaning on these things to a point where if you go any futher something is going to break!!
Reservoir lid was open.

Pistons should move fairly easy when the nipple is cracked open right?

Fluid did drain from the inside nipple slowly but I can't move the pistons.

Any ideas? Can the pistons get jammed?

Thanks in advance.

Try it with both the bleed nipple closed, and open. If still stuck after lubing it up a little with some grease, try this bad boy:

http://www.nexternal.com/trgparts/images/01-Tools.jpg

I use it all the time to change pads without bleeding the brakes and it works great. It is a little pricey, but it cuts significant time off of a brake job.

you may have somehow made the piston crooked so it freezes in place- you can pop it out by removing the caliper and using an air compressor to pop the piston out, then check the seals and reassemble.

Thanks for the replies.
Maybe my leverage was a little unbalanced when trying to compress the pistons...I usually wiggle the pads and use them to push back the pistons but this time I could barely get the inside pads out.
So to pop the pistons out I assume you pass compressed air through the nipple...or am I way off?

Yes, you pass in air from the outside. Please be sure to wear eye protection! You don't want any brake fluid in your eyes.

At a minimum, I'd flush the fluid after putting in new pads. You may need to replace your inner seals while you're at it. Girodisc has the kit you need.

you have to remove the caliper from the car, strip the pads, shims and the dust boot of the one stuck piston. then use clamps or wood block to restrict the movement of the three other pistols. keep the bleeder nipples closed, and put in air where the brake line connects to the caliper. a quick burst should pop it free(keep your fingers out of the way). Then wipe down the inside of the chamber with brake fluid, inspect the piston for any significant damage to the sidewalls and reinstall, making sure the piston goes in smoothly. then reinstall and do a bleed. Good luck! ive been in your position before due to a botched brake pad install, and this worked for me.

Cool! I'm interested if this works for the Op!

Good reply!{thumbup}

If I was you I would def pull the caliper off and rebuild the caliper. Rather safe than sorry. That way you can do a thorough inspection to make sure no other issues are present. I have seized my fair share of brakes.. The rebuild process is not that difficult. Good luck.

I've done the exact same thing! Had warped pad backing and all.. I was able to rotate my piston slightly and that freed it up to go back into the caliper.

Thanks for the answers. Took off the calliper and when the pistons were pushed back in straight on they went back in without much fuss so it was the angle of the leverage.
Will still do the rebuild though....any difference in quality between the Girodisc seal kit and the oem Brembo ones?? About the same price down here.

Both do the same thing and contain the same parts I believe, last time I did my brakes I just used an OEM Brembo kit from the dealership.

i know you already got it fixed but this might help you in the future:

http://www.otctools.com/products/dis..._spreader_7034

a little cheaper than that thing someone posted.

Agreed.

Before Girodisc had these available, I actually ordered OEM Brembo seals from Subaru parts direct, was incredibly cheap.

CHeck out post #13 in this link:
https://www.evolutionm.net/forums/ev...g-brembos.html