Miata rear caliper question

[mrtwo]

I'm doing a rear brake job on my 97 Miata. The parking brake adjustment mechanism on the driver-rear will not retract the brake piston. I can move the adjuster out (pushing the piston out), but it will not pull the piston in. There is little/no corrosion evident anywhere on the caliper. I can retract the passenger side-rear brake piston with no problem.

From the brake diagrams it looks like the adjuster screw drives a small gear that turns a threaded rod that extends/retracts the brake piston.

I've also tried turing the brake piston.

I've also tried preloading the piston with a C clamp while turning the brake retraction screw.

I've tried opening the bleed screw while trying to compress the piston.

The brake does not seem to drag in normal operation (pads are not scored and they look pretty evenly worn).

Any suggestions?

Thanks,

Tim R

[DSPDA3]

I had a similar scenario happen to me on the Acura a few years back. However the parking brake mechanism had completely frozen up, and I needed to get a new (reman.) caliper. It's pretty wild getting out of the car at night and the left rear rotor is glowing red from the caliper being seized up. But it sounds like your calipers are operating normally - no drag, etc. Have you tried any kind of brake cleaner, or PB blaster?

[mrtwo]

For what it's worth . . . .

Frozen piston on DR caliper

Siezed slider pin on PR caliper.

Might have been original brakes with 95K?

Everything working now

Tim