I need help, please. I have an 88' xj that had beed sitting for over 5 yrs. The first item on my list of getting it driveable was brakes. I have replaced both rear wheel cylinders and all hardware and shoes. On the front I hace replaced both rotors and pads. I bleed the system with no success, still had no brakes. Only had slight pedal after pumping and holding. As soom as I released the pedal, it would go to the floor. So, I replaced the MC last night and bleed the system again. Still no pedal, I can pump it up and as soon as I release it,the pedal goes to the floor. I am out of ideas.

 

what do you mean goes to the floor .does it do this by it self or the nex time you push it and did you bleed in sequence

 

the next time that I push the pedal, and yes I bled it in sequence. RR,LR,RF and LF.

 

did you bleed tillall the air was gone

 

yes, I have bled it several times to the point that I'm getting fresh clean fluid at all four corners.

 

did you adjust the rear brakes

 

Yes the rear brakes are adjusted.

 

with it not running will the pedal pump up to the top and be real hard to puch

 

with the engine not running, no the pedal will not pump up and be hard to push.

 

booster must be bad ?

 

you did start it recently so vacuum was present at the vacuum line on booster

 

yes, i recently started it...the booster shouldn't have anything to do with the closed hyd. brake system, the booster only makes the pedal easier to push......the only thing that I can think of is that the new mc is bad.

 

when you pushed the brake pedal down your pushing on the arm in the booster which in turn pushes the rod comung out of the master if the booster was ok the pedal should have got hard as arock like the old manual brake cars get in a nother car and with the motor not running pump up the pedal see what happen but hey what do i know ive omly been doing automotive for 30 plus years

 

this issue troubled me for two weeks, turned out it was the front calipers, auto zone or wherever i got them had the wrong pn so i had a right on a left and a left on the right. The way to check it is:

Loosen the bleed valve on either left or right front brake, fluid should freely come out without you having to pump it. It kinda self bleeds. if it doesn't You may have them reversed.

either way the bleed nipple for front or rear needs to be at the highest point at the top.

 

you had them on upside down that will do it