No Brakes!

[Outlaw]

My Jeep has been sitting at my shop for weeks now. I have tinkered with it off and on between customer vehicles and on slow days. I have a trip planned for the weekend of the 15th and need to get my brake situation figured out so here goes.

Fisrt things first, my Jeep came stock based on the VIN with ABS. Previous owner took it upon themselves to remove said system and I have a pedal that goes all the way to the floor when the engine is running.

I started with the rear brakes, replaced the shoes and the wheel cylinders (leaking) turned the drums and adjusted them, still no pedal. I then replaced the brake lines in the rear and bled the sytem.

I replaced the Master Cylinder with a non ABS master cylinder and replaced both calipers up front, along with new pads. Bled the entire system again and still no pedal.

I removed the proportioning valve and dissasmbled and cleaned it, no longer available from Jeep, and still no pedal!

Has anyone run into this issue before and if I bypass the proportioning valve is that going to make my brakes so sensitive that if I think about stopping it will lock them up. I am at a loss... Myself and two of my technicians are stumped. Thanks in advance for any thoughts or help on this!

[XJ Rat]

When you say no pedal, does it go all the way to the floor? If so, how do you bleed brakes if the pedal goes to the floor?

Is there any type of adjustment on the pedal travel? Not sure on the XJ, just thinking out loud.

[4.3LXJ]

What procedure are you using to bleed the brakes?

[Outlaw]

I have had a tech in the jeep while I'm underneath it.... pump, hold, crack the bleeder screw. it will build some pressure when it's not running... I have tested the brake booster and it tests good. The pedal goes to the floor when running. It is not a fade away it is just straight to the floor when running. I thought brake booster but if that were to fail then I would have a pedal rock hard, at least in my past experience...

[4.3LXJ]

Something must be wrong with that booster then. Your rod from the pedal does not go all the way to the master cylinder. Maybe you need another booster.

[Joliet Johnny]

Is there a difference between the proportioning valve for the ABS vs no ABS? Im from the sport compact world and my Civic had that problem but I replaced that part with one from an Integra and that solved my problem.

[Outlaw]

Is there a difference between the proportioning valve for the ABS vs no ABS? Im from the sport compact world and my Civic had that problem but I replaced that part with one from an Integra and that solved my problem.

I talked to my parts guy at the Jeep dealer and he said they have different part numbers but both have been discontinued... JY part may be an option but its a chance.


Something must be wrong with that booster then. Your rod from the pedal does not go all the way to the master cylinder. Maybe you need another booster.

I thought this as well but even with my cost they are expensive... I may try that but I was hoping maybe a by-pass from the proportioning valve may help. Dont have a lot of cash to throw at it.

Thanks for the feedback, any other thoughts are appreciated and I will keep y'all posted. And post pics from the up coming camping/wheeling trip

[oderdene]

what about pick-a-part?

[LizardRunner]

you may have to use a proportioning valve from summit racing or Jegs. disc front, drum rear really needs one of these valves to not lockup.

[ice_cold]

Ok, you say it goes to the floor with it running? But not when the engine is off?
If thats the case, proportioning valves have nothing to do with it. It definitely sounds like either you vacuum source is wrong for the booster or you booster is FUBAR'd.
Do you get pedal pressure with it off and pumping the pedal? What happens if you get pressure then start the Jeep?

[default83]

yeah the vacuum could be off, but my money would be on the booster.

[Outlaw]

Ok, you say it goes to the floor with it running? But not when the engine is off?
If thats the case, proportioning valves have nothing to do with it. It definitely sounds like either you vacuum source is wrong for the booster or you booster is FUBAR'd.
Do you get pedal pressure with it off and pumping the pedal? What happens if you get pressure then start the Jeep?

I get about half a pedal when not running, I think that is mostly due to the fact there is alot of slop in the pedal assmbly (being fixed) as soon as I start the jeep all pressure goes away. I can stop it but it is like a slow rolling stop.
Ordered a new booster, it will be here friday. I will keep y'all posted. Thanks!!

[Outlaw]

Ok so the brake booster corrected my no pedal issues, but now my shift interlock is not working... more details to follow :bang: