Seized caliper piston

[Matt Vangaalen]

My driver side front piston is seizing up, causing the pads to rub. Any thoughts on a way to free up the piston?

[Rob Armstrong]

Get a c-clamp and compress it then get somone to pump to extend the piston. Do that a shitload of times till it compresses easily.  When I did it I couldn't compress at all. Then after awhile it started to go in. Then after awhile longer it compressed easily with a finger and thumb only. 

[Matt Vangaalen]

I put fresh pads in yesterday, compressed the piston via c clamp. Tomorrow I'll put it through a few cycles. Thanks

[KevinBuckham]

Pistons can obviously seize, but check your slider pins too.

[Lowell Foo]

If the pistons are actually seized, you need to take them out and clean the rust off or it will just happen again.  I see a lot more slider pins with rust issues though, so check those first.

[John Hartman]

I say just get another caliper.  No scratch that, get a pair.  the other one will most likely go fairly soon too.

[Graeme H Burvill]

i don't know how readily available rebuild kits are for calipers, but unless you can get a new seal you need two calipers. If you can get new seals, i say go lowells route, resurface the piston and the bore, lubricate the bore and piston with brake fluid and reassemble.

[John Hartman]

you will also need a correcly sized brake hone for that cylinder bore too, and know how to use it.

[Matt Vangaalen]

Hmmm. You guys have opened up a new world to learn. I better do it right brakes are more important than power. Thanks for the input.

[daniel Dee]

use a SOS metal cleaning pad to clean out the bore til it is smooth. You can placed it on a drill if you like...
Reassembly with brake fluid ....should be fine.....Get new seals if you can.