no brakes

[project88mj]

ok here is the story i first realised that i had no-to-bad rear brakes

so i took them appart and changed the shoes. still nothing. so i blead them twice and still no brakes can anyone help me? :headpop:

[Eagle]

Do you still have the rear height-sensing proportioning valve? If so, there is a special procedure for bleeding the rear brakes. I posted it verbatim from the FSM a few months back. A search should turn it up -- I don't have it bookmarked or I'd give you a link to the post.

[project88mj]

so what do i search for?

[smartazz19]

so what do i search for?

 

http://comancheclub.com/forums/viewtopic.php?t=4917 :cheers:

[project88mj]

okay i read through it and didnt see how to remove this part can some one tell me how ?

 

right now when the rear axle is on jack stands and the truck is running and in gear. i can press the brakes to the floor and the drivers side will slow down but will not come close to stoping.

 

if i could get them to stop that would be great

 

where i live there is a lot of sand and gravil on the roads (expecily after the rain) many times i have had to HIT the brakes HARD and all that happens is the front lock up and i slide really bad and more scary really really far

 

so long story short i would like my back brakes to lock under HEAVY loads in stead if the front.

[Eagle]

You have asked two things in one thread. Do you want to bleed the rear brakes, or do you want to remove the rear proportioning valve?

 

Personally, I blew up my rear proportioning valve so I had to remove it. But you should realize that if you remove it, when you slam on the brakes like in a panic stop, there's a good probability that your rear brakes will lock up before the fronts, and that usually results in a spin-out. Being the olde pharte that I am, I grew up learning to drive decades before cars had proportioning valves, so a bit of fishtailing in a panic stop is normal to me. To you younger folks, it's probably better avoided if you're not expecting it and ready to deal with it.

 

Try adjusting your rear brakes and then bleeding according to the link provided. If that doesn't work, then consider removing the rear proportioning valve.

[project88mj]

i may be young but i drive old stuff. i blead them and got no results so

 

how can i remove the valve?

i appoligise for all the spelling errors and the confusion in my questions? :oops:

[Eagle]

i may be young but i drive old stuff. i blead them and got no results so how can i remove the valve? i appoligise for all the spelling errors and the confusion in my questions? :oops:

Did you bleed them according to the specific procedure in the link someone posted? If not -- then you wasted your time. There are TWO lines going from the front of your truck to the rear brakes. If you don't follow the exact procedure spelled out in the factory service manual, there's a good chance there's air in the other line and that's why you have no rear brakes.

[project88mj]

yes sir i have

[maddzz1]

Didnt someone else just hane this same problem and it turned out he needed a new booster.

[wranglercory]

It is pretty straight forward. First go to a junk yard find a mid 90s cherokee, you will be looking for a prop. valve. This is up front in front of your booster, you will need this. Then after removing the old prop. valve install the new one from the JY. You will need to basicaly find one of the two brake lines going to the rear and you will use it to run the rear brakes. I ran my line into a T valve looking thing in back that was already there. I capped one input off and ran the brakes straight from there. I hope to get a thread with pictures on about how to do this. The line going into the front of the prop. valve will not be used on the new setup.

[Eagle]

It is pretty straight forward. First go to a junk yard find a mid 90s cherokee, you will be looking for a prop. valve. This is up front in front of your booster, you will need this. Then after removing the old prop. valve install the new one from the JY. You will need to basicaly find one of the two brake lines going to the rear and you will use it to run the rear brakes. I ran my line into a T valve looking thing in back that was already there. I capped one input off and ran the brakes straight from there. I hope to get a thread with pictures on about how to do this. The line going into the front of the prop. valve will not be used on the new setup.

Saving that tee fitting is potentially a huge mistake. You'll still be connected to two lines, doubling the possibility of a rust-through causing a loss of rear brakes.

 

It's far better, whether you keep the MJ front metering block OR convert to an XJ front proportioning valve, to rip everything out and run one, new line from the front to the rear hose.

[UNL1MTD]

you could have air in the lines, but maybe you just have two bad wheel cylinders? I know both of mine were shot when I got my MJ.

[project88mj]

well i replaced the wheel cylenders

[smartazz19]

did it fix it??