I've had a "slow leaking" rear brake on my 89 vette for a long time, too lazy to fix, so I'm on it now.

If the car sits, I'll find a little quarter size puddle of brake fluid near the tire sometimes, or I'll see the inside sidewall look like it has some fluid on it. But I figured it was the line and I follow that but it doesn't seem to be the line or the connection? I pulled it apart and I still can't say for sure where it is??? I know these calipers are somewhat suspect.

But I did find this and this seems odd, these rear calipers have the integrated parking brake and then the brake piston is inside of that. With the system fully sealed, I've not opened anything I can easily pull the piston out like 1/2" and push it back in as well???? If the system was sealed wouldn't that be hard to more with you hands?

The red outline shows the piston I'm able to move.


Just curious about this piston moving so easily and anything else I should check. I figure it might be good to put a block of wood into the caliper and then have someone press the brake, maybe under load I might see some fluid leaking someplace?

Interested in other ideas if anyone has run into something like this.

 

I think your referring to the Clamping Rod, this moves in or out freely when the caliper is removed from the vehicle. I would pickup a rebuild kit and go for it, there're not that bad to rebuild,, and the Piston dust boot just slides into position, so you don't have to fight it.. The hardest part is wrapping your head around the design of these units..

The one thing the author does not go into; is the Brake Lever free play adjustment. This is very important in that if not done correctly you will either experience a dragging brake, or; a lack luster parking brake performance

http://www.stevenemichael.com/57Corvettepage13.html

 

OK, good to know that this part of the caliper is ok to be moving without hydraulic pressure. I still need to determine where the leak is, I think I'll try to pump the brakes with a block of wood in the caliper to see if I can find something. Don't want to rebuild unless that is truly the cause.

 

Many replace the rubber lines with stainless steel.

 

Yes, it's had stainless for years back when it was my autox ride, lines look good.