Urgent help needed - rear caliper piston

i need help - i am in the process of re sealing my rear caliper pistons. i have done one but i cant get the other piston out, has anyone got any suggestions how to get it out without bleeding the brake. thanks

If you have had the piston out you will need to bleed the brake regardless, unless you did it all submergrd in brake fluid. To get the stuck piston out use a G-Cramp on the one that will move to fix it in position and SLOWLY and GENTLY pump the rear brake pedal to cause the other piston to move.

[Viney]

Take it off. Its a piece of p*ss to bleed the rear brake. To do the job properly remove the pistons, scrape out the corrosion, give the pistons a buff with some wire wool, new seals, refit pistons using red rubber grease job done. Just remember that there are 2 Bleed nipples.

[Spanner Man]

Morning all.
If you have already stripped the caliper into its two halves, it'll depend on whether there is any of the piston protruding. If there is, a trick I learnt may years ago is to put a decent sized jubilee clip around the protruding part and then lever evenly either side of the clip. Obviously you have to make sure that the clip doesn't slide on the piston, for it will score the piston surface.
I have a tool for pulling caliper pistons, it works like an expanding internal puller. However they're quite expensive, so it's not worth purchasing one for just one job, so maybe you can find a local shop who has one and can remove it for a few bob.
If not the only alternative is to rebuild the caliper, bleed it up, and then as suggested hold the piston on the good side and gently pump out the stuck one. Bit of a time consuming pain, but its better than ruining the piston trying to remove it by another means.

Cheers.