Sticking rear brakes

[pejohnson]

A few weeks ago I heard a high pitched nose when I was driving with the windows down from the rear of the car. When I go out and walked around the car I spit on my brake drums and the right rear (RR) brake was smoking hot. I instantly thought it was the caliper sticking so I replaced it with one I picked up from the junk yard. I pulled all the brake lines, rear calipers, drums and pads of the junkyard car as they looked brand new. Anyways put the different caliper on and still have the same problem. So I dug deeper. I inspected the slide pins and they are greased and slide perfectly. I inspected my stainless steel brake lines and they look fine. So I thought it had to be the e-brake as it has always been hard to engage. I disconnected it and took the car for a short test drive. Still feels like the caliber something is sticking. When I jack the rear end up and spin the LR, it spins so much freely than the RR.

I can't imagine the new/used caliper is bad. I have ruled out the e-brake. I can't imagine the SS brake line is bad. I'm really at a loss. Any thoughts?

Also just out of curiosity how do you check to see if the caliper is bad?

 

[Irish Pride]

Check the bias valve. See if its releasing all the way. Mine was so rusted is was locking up both calipers.

 

[Irish Pride]

When you installed the caliper you got from the junkyard did you rotate the piston in?

 

[ShadetreeSHOguy]

Crap, i never thought of doing that Chad. Now i gotta check mine, just replaced both mine!

 

[thegreatbriguy]

Check the hose between the brake line and the caliper. It swells and doesn't let the caliper release. Sometimes it's hard to diagnose, but if you checked everything else, it's probably this.

 

[luigisho]

^^this would be my next move. then prop valve

 

[pejohnson]

I have stainless steel lines.

 

[pejohnson]

So Chad appears to be correct. I zip tied the bias valve together and the RR brake appears to be not sticking now. I failed to mentioned I installed adjustable control arms and probably didn't install the bias valve spring assembly correctly. So here is my questions now:

1. Why not just keep it zip tied shut? Doesn't this keep the brakes operating more aggressively like the bias plugs?

2. If the answer is I should undo the zip tie, how do I set the spring tension correctly on adjustable control arms? I saw a thread that someone used a hose clamp and wrap the bracket around the round control arm. Great idea, I just don't know where the correct setting is.

3. Maybe I should just say the heck with it and install bias plugs. I have Koni strut, Intrax springs, heavy duty sway bar links, and the Gen I rear sway bar link. My point is that my suspension is stiff and will not act the same as a stock vehicle. Meaning I don't think the bias valves will engage with the bias valve set up as the rear end will not move as much around turns or on hard stops.

4. I do have a new bias valve assemble I pulled from a junk yard. I have no problem installing that but based on my comments above I'm not sure it will solve the problem with my suspension set up.

Right now I'm temporarily keeping it zip tied until I figure out what to do.

Thanks for your feedback.

 

[pejohnson]

http://www.shutterfly.com/lightbox/view.sfly?fid=ad5240a9843437246d9889752d9a603c#1351467583744

http://www.shutterfly.com/lightbox/view.sfly?fid=ad5240a9843437246d9889752d9a603c#1351467583744

 

[pejohnson]

pictures

Why can't I get the pictures bigger? Technology and me are like oil and water sometimes. I know someone on here explain how to do it but I can't find that thread.

 

[pejohnson]

So I replaced the proportioning valve and still had the problem. I finally gave up and took it down the street to my mechanic. Turns out is was bad calipers. He replace both of them and now they work great. Lesson learned here is to buy new calipers rather than try to use junk yard ones that look brand new. New calipers are fairly cheap in the grand scheme of things considering what I just paid for this brake job. At least I can sleep at night now knowing I've got great brakes again.

 

[FamilySHO]

Secoond lesson is that re-built calipers can be iffy. Went through the same routine, replaced the proportioning valve and brake line and still a caliper that wouldn't compress either with the parking barke or pedal. Replaced with a Motorcraft rebuilt unit in the hope that their rebuilds are better quality. So far so good.

 

[luigisho]

While rebuilt calipers can be iffy junkyark calipers are usually a bad idea. That's alot of sitting around in the elements without use to keep things from seizing up. I'd grab j/y brake parts for cores for expensive upgrades maybe.

 

[FamilySHO]

"I'd grab j/y brake parts for cores for expensive upgrades maybe."

Expensive upgrades? Don't even need that as the core on a Motorcraft caliper is $100!