Cleaning the rear calipers from '73 2.0, installing new rubber boots, etc. Advanced the pistons to clean things before installing the new rubber boots and the piston on the side opposite the parking brake lever went back in fine. In turning the allen screw on the parking brake side nothing happens- can't get the piston to go back in. Keep turning the screw and acts like it is stripped- can't move the piston back manually either with a C-clamp. What did I screw up?

Put the c-clamp down.

Did you put new seals in? Clean the sides of the piston?

Are you turning the screw counter-clockwise?

Try a high speed air wrench. The internal mechanism of the piston is spinning and a high speed wrench with a 4mm hex on it will overcome the inertia with velocity. Careful, it will go in fast once it catches. Short bursts.

Eric,

Thanks- I'll try that first and then maybe let you send me a rebuild set...

Sent you an email...