Rear brake calipers

[moosetestbestanden]

I've finally gotten round to putting the rear brakes back together, or so I thought. But the pistons in the calipers won't budge. I've taken the calipers right off of the car (I'm getting rid of the parking brake - it's sooo heavy :-O) so there's no hydraulic or cable tension anywhere . I remember this being a bitch when I built the car but now it's simply impossible.

I've done this on other cars before. Shouldn't the pistons compress (I've tried pushing & winding - no dice) so that the pads go in and then the caliper w/ pads goes over the disc? What am I missing?

[GWise]

You have to twist them (via a caliper twist tool or some pliers). You will have to push (harder?) them in as you twist.

Cheers.

EDIT: Just thought of something - maybe remove the Cap on the master to allow it to vent as you move the piston back and displace the fluid.

[Doug Liedblad]

You should not have to remove the cover as there is a vent hole. DO watch the fluid level as if you've added fluild as they went down, it will come back up.

You can buy an inexpensive wind back tool from a local parts store. You do have to push and twist but it should not be too hard.

[Elv15]

Chris,

Have you tried both sides or just one side? If you've only tried one side and it's not moving you may have a stuck piston in the caliper.

Tom

[GWise]

You should not have to remove the cover as there is a vent hole. DO watch the fluid level as if you've added fluild as they went down, it will come back up.

You can buy an inexpensive wind back tool from a local parts store. You do have to push and twist but it should not be too hard.

From what I remember on my car, there isn't much of a vent hole. It would be easy to clog.

This should help you out:

http://alcester-racing-sevens.com/rear_brake_pads.htm

[slomove]

I had the same trouble and found the rubber boot sticking to the piston due to grime and dust. A quick shot of WD40 made it twist and move much easier.

[moosetestbestanden]

gwise, thanks for the link. This quote...

"It takes quite a lot of effort to force the pistons back into the calliper body. A lot of effort."

seals the deal.

As I mentioned, I took the calipers right off of the car. It was clear that the force required implied that I stood a very good chance of doing something stupid and breaking something. I guess I'll have to get a proper tool for winding. Whatta pita (well, pitw - wallet - actually). The AP brakes at the front have no such issues. It's almost enough to make me spend the $500 or so for the racing rear calipers. Almost.

[Boxologist]

have u tried a c-clamp in the sliding rear caliper. I know it has always worked on fixed calipers.

[Michael Murphy]

Talk to Doug about his wilwood calipers before you buy the bespoke English thing. Might be cheaper.

[Doug Liedblad]

I've not yet done the Wilwood upgrade to the rears, only the Outlaws to the front. Magnus recently did his fronts as well - we have the non vented disks.