Working on the right rear brakes of a 98 Prelude. The piston is spinning, but isnt compressing. I have the bleeder screw opened and have turned it many times in both directions. Any ideas? Thanks in advance!

 

Sounds like it's time to replace the caliper.

 

Did you take the master cylinder cap off to let it grav. bleed?

 

So come to find out I wasn't push in on the piston enough while I was screwing it. All back together and it's working fine.

 

ebrake is not on correct ? It wouldn't spin if it was on most likely but its worth a shot.
Why would you turn the bleeder screw in both directions, lefty loosy righty tighty.

Also gravity bleeding is a last resort in just about all cases. You want to limit the fluid's exposure to air since its hydroscopic, which means it absorbs water. By exposing the fluid to air you run the risk of lowering the fluids boiling point, the water can cause corrosion on the internal of the braking system.