I spent four hours working on the right rear brake. Grrrr! Had a new rotor and pads in place, went to put the caliper back on and found out that the piston isn't pushed in far enough. I used a brake caliper tool and no matter how much I turn the thing it won't go in any further. It just spins and spins. I've tried removing the master cylinder cap and unscrewing the bleeder screw. Parking brake is also off. I've also tried pumping the brake pedal to push the piston back out and used the tool to push the piston back in but it still wouldn't go in far enough for the caliper to fit over the new pads and rotor. I got so pissed I put the old parts back on and called it a day. Four hours wasted!
Here's a picture of the caliper piston showing how much it still sticks out. Is it time for a new caliper?