Brake issues!!!
 

I'm having issues bleeding the brakes on my 86 1/2 ton wrangler. I got the back brakes to bleed and when I went to start in the front once they got a bit of fluid they lock up and don't seem to want to unlock. I've changed the master cylinder and the proportion valve on the frame and it doesn't seem to have helped and I've even taken the calipers off and pushed the piston back in and they don't take much effort to push back into place. I don't think it could be the calipers as both sides lock up. Any advice would be greatly appreciated.

Re: Brake issues!!!
 

Calipers can get sticky and not release. Rust and heat can cause them to run tight and not release. I would assume that is the issue, as you mentioned both sides that is odd but not out of the realm of possibilities. I have had to brush an file to fix this in the past or calipers are cheap to replace.

Re: Brake issues!!!
 

Ya it's just weird that when I had them out on the bench the piston compressed without much effort and when I put it back on the slides were loose even.

Re: Brake issues!!!
 

Clogged brake lines??

Re: Brake issues!!!
 

I had a similar problem one time, the brake bleed screw was totally clogged with rust and crap!

Re: Brake issues!!!
 

I know they aren't clogged because I've got some brake fluid coming out. Would the proportion valve be causing issues?

Re: Brake issues!!!
 

By previous experience, I noticed that a semi clogged brake line can let fluid in, due to the high pressure applied by the hydraulic system as you push the pedal, but it's not so free as to let fluid return back by itself. If you disconnect the line/s from the caliper, can you see it dripping fluid by gravity? it should.
Bruno

Re: Brake issues!!!
 

Well it's for sure one clogged line on the passenger side and I'm not sure about the caliper but I think I might put new ones on anyways and then every base is covered I guess.

Re: Brake issues!!!
 

I have had the inner liner deteriorate and cause issues. They can get a "flap" and shut off the flow of fluid. Loosen the line at the entrance of your rubber lines on the front to see if you are moving fluid well to that point.

Re: Brake issues!!!
 

Yeah I un did both ends of the steel line and blew through it fine just that stupid rubber line causing all my issues I think and a calliper because even unhooked it wouldn't release and had to pry it off

Re: Brake issues!!!
 

Does anyone know what style of brake system it would have? Jb?