i serviced my twin pots at an aircond shop cum workshop, my pistons got stuck, tried to remove it for 1hr ++ but failed, lastly he told me to find a new set of calipers....so i went to a few halfcut shops....but unable to find...if there is will costs rm400++......
lastly i came back & told the bad news to my mech.....he suddenly had a tought. he covered all the outlets on the caliper, then insert the compressor (used to do compression test on cooling coil or compressor to check for leaks), suddenly the pistons just popped out with a loud sound.....guess those pistons had been badly stuck inside.
was relieved in the end...cost only rm100++ include service kit & workmanship.