superj

i did a search and read roughly 3 pages of posts but no one has actually fixed the problem, or answered that they fixed their issue after posting.

this is on an 87 model, no abs, with a booster, 4.0, auto, 4x4. (not sure when abs came on these things but i know my 85 bmw had abs, is why i made the comment about no abs)

i had a rear line break the other day, one of the hard lines at the wheel cylinder, and it caused me to lose fluid and blah blah blah, you know the deal when that happens. anyways, i replaced the whole rear brake set up. i used a wrangler flex line with that new poly hard line stuff to each side and speed bleeder valves in the cylinders. i had a previous low pedal so since i was in there doing all that work, i replaced the master and made sure the booster wasn't sucking fluid in. i attempted to put speed bleeders on the front but those factory suckers are not coming out. they bleed fine and hold pressure but will not come out and let me put in the speeders. i bench bled the master also.

anyways, new master cylinder, new hardlines and flex line in the back, new speed bleeder valves, booster works, pads and shoes look good, rear drums cleaned and greased..........and still no pedal. brakes start working as soon as you reach the point where the booster starts sucking and weakly try to stop you all the way to the floor where the fronts will start working a little more and if you are going under 5mph will lock the tires up.

whats up with this propertioning valve? the backs bleed out fine but seem to not work at all on the street. since fluid is coming out i am lead to believe that proportioning valve is not locked up and is working properly.


any of you guys who made this type of thread previously get your stuff working? any insight on what to do? i have new flex lines to put on the front, from a wrangler but i was holding off swapping them till i put the front part of the lift on. i am thinking of borrowing a brake bleeding pump from a buddy and trying that out. maybe its just air?

robertj

After fighting problems like yours in the past I finally broke down and bought a reverse bleeder. Best investment I've ever made and makes bleeding brakes a breeze even when replacing major components.

fantic238

If you removed the master you need to bleed at the master too. How's the hand brake? did you register the shoes so that they go fkn tight in the drums?

93gc40

No Vacumm leaks? Boster bad or air or debris in the lines. Rear adjusters could be loose.

okcjeeper

which bleeder did you get?

dyte2004

i had same prob after changing rear cylinder i had to invest in a decent bleeder (runs from my compressor)the xj seems to be a ***** for bleeding the rear for some reason

Gillette1987

agreed with ^^ Ive had a similar problem with my 80 XJ. No rear brakes for about a month before I even realized the passenger rear drum brake line snapped at the "T" intersect that heads back to the booster fluid resovoir. I replaced all the lines and still had no brakes, turns out my hand brake adjustor was on so tight that it wore down the shoes inside the drums. I replaced everything inside the drums and it solved my problems

"EDIT" i also had some debris inside the brake line for the front, this also caused me some issues.... i just used a gallon to fully bleed out the system and out came dirt and a few pieces of grass and pine needles (????????????) Now the brakes are functioning like they should

superj

well, i will bleed some more then. i didn't mess with the e-brake but i will check it tomorrow since i have soccer practice today. i will let you all know what the final outcome is and what fixes it

robertj

http://www.bonanzle.com/booths/etool...Clutch_Bleeder

superj

ok, borrowing a buddies bleeder tommorrow but might not be able to do the job till saturday. lots of soccer days during soccer season.

SRT-10Jeep

Good luck and with the soccer also.

superj

my kids are doing great. i coach 10 year olds and we are doing ok, won more then we lost. its a recreational league so the main coaches pick all the people they want and then i get all the left over kids they don't want. works great for me because i get all the kids who have never played before so i teach them how we played in socal and hawaii, not the way they teach here in texas.

mrmikey32

just had this same issue, but it was a front line. goto autozone and you can rent a vaccum pump. fixed all my issues in about 10 minutes

superj

turns out the front plunger on each of hte wheel cylinders was stuck. don't know what happened since i cleaned all those when i bought the jeep but they are being replaced today and a new kit is being thrown on the back for brake springs and stuff

superj

ok, new wheel cylinders did not fix the issue. i am now going to repull the drums and have them mic'd to make sure they are within spec. they look like it though, no lip on them from the shoes. it appears the rear brakes have not worked for a while.

i enlisted in the aid of an old school mechanic who lives across the street from me. while i pride myself on knowing the older systems well enough to have never needed to go anywhere, there comes a point where you are beat and you just have to man up and know when you are there. i am there. he came over and looked it over and did some messing around and said everything should be fine. he sees no reason why the rears don't work unless the arm that goes from the pedal to the master is not adjusted right. he said it might be set to far out and could be pushing the first plunger too far to where it passes the holes where the fluid is, at which point it makes the maste cylinder into a push and pull pump as it will get fluid in between the two plungers and make pressure when you stomp the gas but make vacuum to pull the fluid back when you let off. he said this could be giving me my no rear brake issue since hte fronts work perfect.

so, after i get the drums mic'd, if they are good, i will pull the master and measure the length of that little rod and make sure it is not pushing to far into the bore.