XJ Brake Upgrade (Continued frustration)

Bleeder has to be above the hose. And it is easy to get them on the wrong sides, seen it done before. Hope that is your case, easily fixable :)
 
Few questions, How much pedal travel do you have before it gets tight?

I know you bench bleed it. Was it with the small plugs doing short 1/8" strokes? (just making sure your methods are the same. It took almost 80-100 to bleed the last MC (ok it was 1-1/8" but normal pumps did nothing..

Also you mentiond debris/junk in the prop/residual valve? What exactly was in there?

Lastly, most of the time a stuck/frozen caliper will extend just not retract. Same with a pinched line. Pedal pressure can push the fluid but the caliper can't retract on its own.
 
Saw your other posts.. Wanted to make sure this is answered for people searching...

From your other post sounds like you had the calipers installed on the opposite side? (The bleed screw was not at the top?)

So you flipped them and..................
 
@yager first post:
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Pedal travels about 2-3 inches before hardening.

Bench bled doing small strokes. Did about 15,0000 of those. Eventually pumped it around 2 inches. I bled it in the the vehicle.

The prop valve had old fluid in it. It mostly was just dark in color. There wasn't a lot of trash, just crappy looking fluid.

The calipers retract.


@yager second post:
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Micky flipped them for me, but we haven't had time to bleed them and see what the outcome was. I will be doing that tonight. (Went to pickup another truck last night.)
 
cltdba said:
**Snip**
So, last night we took apart the proportioning valve. Cleaned the crap out of it and put it back together without the o-ring and bled it. Doing this is supposed to allow more pressure to go to the rear brakes. Well that had no effect whatsoever. We noticed a hissing sound coming from around the power booster where it mates to the master cylinder. Took off the master cylinder, removed the rubber seal on the booster, cleaned it, cleaned around the booster, and even ran some black RTV around the master cylinder. Buttoned everything back up and no more hissing sounds, but still no brakes.
**Snip**
Click to expand...
Wwildman said:
Did you do this part to the prop valve ?
http://www.4x4wire.com/jeep/tech/brakes/xj_wjbrakes03/valve/index.htm
Click to expand...

Yep
 
Where are the brake lines from the master to the prop valve ran /
Front of master supplies brake pressure to rear and rear supply pressure to the front . If they are not routed correctly the rear will not stop . I am in the middle of doing this myself . but using a 8.25 with zj rear disc and a zj master with a 99 xj booster .
 
Great news guys! Brakes are working GREAT!

It was indeed the calipers that were on wrong. As you recall, Micky had already swapped them around to the correct sides. I got there tonight around 8:30ish. The brake pedal was already rock solid. I busted the bleeder loose on the driver side and it had a ton of air pressure behind it. Anyways, we bled the brakes and ran about 1/4 - 3/8 of a large bottle of brake fluid through it to make sure we had all the air out. As we were bleeding I could see the calipers compressing and the hoses flexing. That was a great sign! After bleeding I slammed two lug nuts onto the rotors without tires and ran it in 2WD and the tires were stopping. We threw the tires on Jeep and ran it in 2WD (still in the air) and it was stopping the wheels just fine. Boy I was excited!

We took it for a test drive and the brakes were working great. The pedal was firm all the way to the top. I had previously adjusted the length on the shaft in the power booster to try and get more stopping power. Well as the brakes warmed up and the fluid expanded the brakes started grabbing. I could tell the Jeep was having to work harder so we pulled it back in the shop and and removed the MC and shortened the push rod. Backed the Jeep out of the garage and voila. Brakes were perfect! I can lock all four up on gravel. Didn't drive on pavement.

Also found out I had my serp belt entirely too tight. I now have to replace an idler pulley tomorrow. She's wobbling and squeeling. Loosened her up a bit so we could do some test wheeling. Boy it was nice to wheel the jeep. Seems like it's been apart forever and it's only been three weeks.
 
Oh yeah! Can't wait for Harlan! I'm going to take it easy at URE this weekend (yeah right) so I don't break anything before Harlan. :)
 
Thanks

Thank You to all who posted before.
I just swapped out the Bendix 9 system for a 96 power booster.
Only mods were bending new lines and moving the washer bottle forward an inch. Now, what do I do with the junk that was pulled out?
 
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