I need help with this. The other day while driving to work, the rear brakes slowly started to grab. Within 1/4 of a mile, they were locked down and I had to force it into a parking lot. I sat there for a few minutes and checked everything out. It went away after a few minutes and I drove off. Then on the way home, I sat at a light, when I went to drive off, they were locked. I forced it through the intersection and pulled over and again after a few minutes, it released and I drove off. What gives? Water in the lines is what a friend said. I will check this weekend, but am looking for some guidance. This is on an 87 TII. Thanks everyone.

 

What does the pedal feel like when this happens? Does it go spongey? How about the e-brake, is it loose? Any wierd sounds?

Are you SURE it's the brakes? A siezing rear end can lock-up too. It's unlikely, but a possibility.

 

I had this very problem before also. The rear brakes float on pins, I've worked on /own several Rx-7s and have noticed if regular brake maintaence wasent done and those pins / sliders werent cleaned and lubed from previous owners they rust and pit BADLY. My rear brake slider/pin was pitted fairly bad which caused binding and sticking even after a good cleaning and lube. Once that brake sticks and your doing highway speeds it heats up really quick and bad. This causes things to sweal due to heat, then as the brake is worked, these now super tight tolerances score and mark pistons, sliders, caliper bores all chewed up and they begine to stick worse and worse needing a new brake assembly. Best bet is to buy a set of used calipers and CHECK the sliders for pitting and go ahead and rebuild them. The rebuild kits are cheap and its easy to do. This has been my observations and experiances...you may have a diferent problem... good luck

~Mike.......

 

Rear caliper pistons hanging up, probably due to contaminated fluid (Just from time/use). Remove calipers and see if pistons can be turned in. If not put a set of rebuilt calipers on.

 

Thanks guys, I've been away from rotaries for awhile and just got theis car on Tuesday. I have never dealt with locking up brakes though. I am sure it is the brakes and the previous owner was less than nice to the car. I am taking care of it all this weekend. Thanks for the advice.

 

One item I'd like to add..If caliper pistons look, turn properly, don't overlook the flexible brake line. If it's deteriorated internally, it will allow the fluid into the caliper, but block the flow back to the master cylinder, hence the "locking" of the brakes. If it is the brake line, you may need to open the caliper bleed valve to check the pistons. Meaning if the line is bad, the pistons won't be able to be turned in because of the build up of pressure. Hope this is clear.