I have adjusted the e brake out completely and have the e brake engaged. The problem is that when the caliber are installed and the e brake is also installed and the e brake not engagued I can not turn the rear wheels.

Could I have faulty calipers? The brakes are from MP Brakes out of North Carolina.

Any suggestion would be helpful.
Thanks
Jeff

Mine stuck a little but the opposite, it took a bit of pedal pumping to get them to release. Tried using a caliper compressor tool or a C-clamp? I suppose it's also possible you have the wrong rotors.

Mine stuck a little but the opposite, it took a bit of pedal pumping to get them to release. Tried using a caliper compressor tool or a C-clamp? I suppose it's also possible you have the wrong rotors.

You can't use a c-clamp or caliper compressor on these types of calipers. The parking brakes function mechanically and have a kind of rachet mechanism to keep them adjusted. The only way to fully release them that I've found is to remove the parking brake arm and back the mechanism off mechanically with the stud the arm attaches to.

From the looks of them (similar to rear Toyota calipers I'm more familiar with) it looks like the pistons could be screwed backward into the caliper, but as yet I've not found a good way to put enough rotorary pressure on the piston to do so, thus I use the "turn the stud" method mentioned above.

It would be nice to know how the factory recommends adjusting the parking brake and retracting the piston. Anyone got a '79 Eldorado shop manual? :)

not a factory repair manual but see if this helps:

http://www.tsmmfg.com/Troubleshooting.htm#2

Thanks, that does help. I guess I had the parking brakes adjusted properly already. I'll check them again before starting to bleed the brakes.

Rich, i spent a few years behind the counter of a fairly reputable part house. i don't know everything, i'm still learning too...

one thing i distinctly remember though is a customer called me and told me that their customer was complaining about the brakes on their car... this company had done a complete brake job and the old lady brought the car back under warranty.

the issue was no rear brakes. it was a Cadillac with rear discs.

the emergency brake is very important on the Trans-Ams and the Cadillacs. as it's used it feeds the caliper piston into the rotor... if the e brake isn't used, as the piston extends and retracts, after a while the pad material is worn away and the brake efficiency is gone, the pedal is lower etc.

e brake usage with the rear discs is needed all the time for proper feed on the pads.

hope i wasn't too wordy and that i explained it OK...


JR

It all helped confirm what I figured out on my own the other night. I have an '85 MR2 that has similar rear calipers so the concept has traction with my own experience. Fortunately on the MR2, all you have to do is turn the piston while pressing and it receeds into the caliper. Makes doing a brake job VERY easy. Same concept on these GM calipers, just harder to retract them.

I had started to bleed my brakes and was making no progress. Come to find out that the parking brake was adjusted on one caliper but not the other so that explains a lot. Unfortunately, the whole brake situation will have to wait until I get the transmission installed since the brake cables can't be installed properly while the trans crossmember is out. The real issue is that the pilot bushing in the crank is too small for the transmission's input shaft (which I didn't find out until I tried to install the trans) so I first need to remove and replace that pilot bushing. I've already broken a bushing puller and haven't moved the bushing at all. Not sure how to get it out now but it's coming out one way or another this Saturday!

Hey Rich, you can hydraulic the bushing out... pack the cavity with grease then insert a solid tool that fits the id of the bushing real close and drive on the tool...

or, what i've done in the past on real stubborn bushings... drill a bunch of small diameter holes in the bushing and break it out.

such as this: http://i7.photobucket.com/albums/y258/64Flyer/pilotbushremove.jpg

excuse the crude drawing :rolleyes:

i'm sure you've probably already thought of these though...


oh, here's the tool i use on my rear discs... don't know if this helps.

http://www.etoolcart.com/browseproducts/Rear-Brake-Piston-Tool----LIS28600.HTML

Well, the puller I tried to use dug deep gouges in the bushing so the grease/hydraulic method wouldn't work. It's in there so tight I don't think it would budge using this method anyway.

Funny how great minds think alike, my plan is to drill some small holes and chisel or cut through the bushing to weaken it so it can be removed.

I always meant to buy one of those tools, but on the MR2 I can turn the piston in using the handles of a pair of pliers. The Cadillac calipers' pistons don't have nice deep depressions as on the Toyota ones, so a special tool would be most beneficial. While doing the job with the stud on the back does work, it's kind of a hassle to take the arms off and put them back on.

Funny how great minds think alike


watch out... some have been banned for that sort of association :rolleyes:

hehehe :D


that tool is priced high at that link... i've seen them for less than 8 bucks ;)

they do come in handy ;)


good luck to ya Rich,


JR