Well in my seeming never ending brake job I just rebuilt the rear calipers and am proceeding to do the front calipers now as one seemed to spring a leak. I thought no big deal two rebuild kits and I'm back in business. Well I got one side apart and I'll be damned if the piston seal ring groove isn't cracked. I'll see if I can get some pictures up. Just wanted to see if anyone ever heard of a problem like this. Thank for any tips or suggestions folks, looks like I need another caliper probably just find a used
1978 mercedes with ATE calipers. I'll try and get a picture its pouched. The ring where the piston seal sits in the caliper is cracked about 90* of the way around the diameter of the caliper piston bore and actually broken up so the metal is raised. Hard to describe will have to get some pictures up, hard to explain.
I think that's just the groove for the dust seal, not the piston seal that actually holds the pressurized fluid. Throw the rebuild kit at it and bleed it. It it doesn't leak, I'd drive it.
It is cracked down to the seal cutout area allowing the seal to move, its cooked. I think when they cut out the seal groove there must have been a bad area in the metal casting. The old seal deformed around the crack which allowed the fluid leak I experienced. Tough to picture.
