Sportsfans,
I'm at wits end. (it was a short trip, i know...)
I have four CNC 603 aluminum billet 4 piston calipers.
They were rebuilt by a reputable racer a few years ago. Then put in a box.
I can not get them to function. The pistons seem frozen in place. Some don't want to bleed.
I have used the master cylinder for pressure as well as 120 psi of air pressure.
At this point I'm ready to investigate sending them to a rebuilding service. But, once you look that up on the interweb there are thousands of options.
I trust the recommendations of folks on this site.
Any idea where to send them?