Baer SS4 Sticking

[ho428]

T4's in front, SS4's in the rear. Right rear will not release, crack the bleeder and have to use force to get the pistons to retract.
I took it apart, found no issues, lubed the seals and re-installed, still tight. Fluid flows fine when bleeding, left rear works fine. I ran these for years on another car, then sat on the shelf for a couple of years, this one is just very tight. Even taking it apart the pistons were really tight to pop out.
Parking brake is not engaged. Any suggestions before I send it to Baer?

[Vimes]

Flex line. They will look perfectly fine on the outside but break down internally and split inside, and the split will act like a one way valve. That would let the bleed work fine and the brake engage fine, but not allow the caliper to release. If there is a metal bracket attached to hold the flex line in a specific place, the bracket can rust inside against the line while appearing fine on the outside as water and dirt collect in there. This squeezes the line down, and acts the same way. The master can overcome the resistance but the releasing caliper can't.

[ho428]

After talking to Tech support at Baer we figured it out today. There was excessive pad taper worn onto the pads, the pistons would push out but **** in the bore, causing them to stick and not retract. I pulled the pads, ran them on the belt sander to re-square them and everything works fine now.
OEM calipers usually don't have this issue since the pistons are a looser fit, these Baers run a pretty tight tolerance so the pads need to wear more even.
Something to check from time to time with aftermarket brakes.

[Vimes]

Wow, not a diagnosis I would expect. Glad you found the problem.

[dhutton]

After talking to Tech support at Baer we figured it out today. There was excessive pad taper worn onto the pads, the pistons would push out but **** in the bore, causing them to stick and not retract. I pulled the pads, ran them on the belt sander to re-square them and everything works fine now.
OEM calipers usually don't have this issue since the pistons are a looser fit, these Baers run a pretty tight tolerance so the pads need to wear more even.
Something to check from time to time with aftermarket brakes.

Good to know! Learned something.

[toddz69]

Thanks for the update - not something I would've suspected either!

Todd Z.

[130fe]

Gordon, sent you a PM.