How do you extract the other brake caliper piston?

OK, so I searched the archives and found some ingenious ways to push out the brake caliper piston. I used the bicycle pump method and have found that only one piston would push out, leaving the other still in place. :? Any suggestions on how to extricate the remaining piston? Thanks in advance!

 

i left mine in diesel,over night,but they do say it can damage the rubber seals around it,as it is hard to get them out if u havnt got an air compresser,ill have a look tomowow,as i have done alot of freeing up pistons,its the after bit,how the h ll did i do that?this is dave her uther half on hear,as i look after the bike for her,,,,

 

I tell you i had one stuck good. I tried and air compressor but couldn't get a good seal. I read about the grease gun method and was didn't believe it. but when I stuck a grease gun on that bleeder and had the caliper out in a few pumps I became a believer!

 

lol o there are lots of ways,

 

The easiest way is to put the Piston you got out ... back in ... then, push the grease to it. When the one you got out emerges half way ... secure it from moving further with a C-Clamp.

The other one will haave to move out as the pressure increases.
Once you have then BOTH out half-way ... Remove the C-Clamp and let them BOTH move with the increased pressure until they fall out (or until you can grab the Pistions by their exposed leading edges and extract them manually).

 

Mahalo for all the feedback! As always, THANKS Rick! I was thinking along the exact same lines with a pair of c-clamps on "free" piston. I think I'll need a small piece of thin bar stock to give one of the c-clamps a perch to clamp on to, as the piston is not so accessible on one side of the caliper.

 

Any idea's on how to free up a seized piston that is in the "out" position?

 

hmmm leave it in diesel,or lots of wd40, maitainance spray, i use to tap it back,and try to tap it out again, with a good pair of grips,is your calliper apart or still in one,piece?

 

Look at the Piston emerging from the Caliper. There should be a shadow toward the end that does not retract in beyond the Seals.

You can grab-on to that "Shadowed" portion with Locking pliers and wiggle it out. Don't mar the Piston inside of the Shadow.

That the Piston is hard to remove indicates that there is build-up of contaminant in the grooves that hold the Seals. When you get the Piston out ... you nave to fabricate a scraping tool and scrape clean the residue and contaminant out of the Caliper Seal Grooves until you are down to bare aluminum.

Once you have the Grooves cleaned-out well ... the Seals will have a slightly increased outside diameter to expand too allowing the Piston to be replaced without too much difficulty.

Use a lot of clean Brake Fluid as the lube when you assemble the Piston back into the Caliper.
A C-Clamp and a socket inside the Piston helps Press the Piston back in the Caliper.