at least not completely. I recently installed 4 wheel disc on the car and the fronts are awfully tight. I have to assume they are running very hot as a result. I haven't done anything to look into it yet but plan to this week. Any suggestions were to start looking specifically? I have a line lock on the car and it works fine locking and releasing. I was wondering if the line lock might be directional but I saw no markings on it anywhere. It may have had a sticker on it at some point but I cleaned it up and painted the solenoid black years ago.
How tight did you make the bearings? Are the front hoses new or used? What happens when you release the pressure from the hose? Do the rotors spin more freely??
Without knowing what all was changed, we can only speculate. I do have a similar experience though. I did a 4 disc swap from manual drum to power disc. I had a brake drag issue that resulted in very hot brakes as well. The rod between the booster and master was about 1/16 of an inch too long causing the brakes to be engaged. I unbolted the master from the booster and found it was being pushed away from the booster and wouldn't sit completely flush without pressure being put on it. So that told me the rod was just a little too long. It was completely cured after grinding down a 1/16th" or so.
It's not the bearings. I always back them off about on flat, and the fact that they are tight even after the car has sat for several days. The rears are fine, there doesn't seem to be any extra pressure on them so I have to believe it's got to do with something not right in the front. Proportioning valve malfunctioning? Everything is new including the braided hoses. My way of thinking is it would be too much of a coincidence for it to be a hose since both the fronts are tighter than they should be. I'm going to back off the fitting to the front brakes and see if that does anything. Maybe my line lock is malfunctioning, yet it works. I have to start somewhere, though.
I loosened both front brake hoses, practically removed them and the calipers didn't release. The right side is tighter than the left. Anyway, I've got an extra pair of original Delco calipers (the pair that were on it when I had the disc/drums) that I'll rebuild when I get time. Perhaps these reproduction front calipers are crap. It wouldn't be the first time. Hopefully that'll do it.
Is the master cylinder correct for disc brakes? I believe drum brake masters use residual check valves where disc masters do not.
Yes, it's specifically for the 4 wheel disc. I unhooked the front hoses this morning and the calipers have not released anymore. Seems like they should have with no pressure on them. I've rebuilt the other calipers I have but I'm not sure if I'll get time to install them before Sunday. Hope they do the trick.
How do the bushings and o rings in the caliper ears look? If they are not in good shape and greased, the entire caliper can become misaligned and jam resulting in binding and uneven pad wear. The calipers need to slide as the pads wear. They sell a special grease for those parts.
I haven't removed the old calipers yet, which are not exactly old. I have rebuilt the spare pair that I have but haven't had time to install them. In addition to the new seal kit, I also got a new bushing and O-ring kit. What kind of grease is recommended for this? I was planning to use Vasoline on them. Maybe a bad idea?
No, not vaseline, they make a specific grease intended for this application. The caliper needs to slide as the pads wear. https://www.walmart.com/ip/Permatex...3835&wl11=online&wl12=124889333&wl13=&veh=sem
Thanks Larry, I'll pick some up today. And I'll pay particular attention to what the current calipers have on them, or don't have on them when I remove them.
Well, rebuilding the old calipers and reinstalling them did the trick, along with the new lube. I still don't know exactly why the repro calipers weren't releasing. No time for that today, but I did have to push the pistons back in with a C clamp.
