No brake fluid at rear axle

[rangercat]

Recently I've been trying to bring my '90 Bronco II back to life. It's been parked for 2 years.
Pumped out the old gas, charged the battery, it started the first time.
On the first test drive, the driver's side caliper partially locked up.
Replaced both calipers, pads, rear wheel cylinders, and shoes, then started to bleed the brakes. Found no fluid going to the rear axle.

In swapping out the old rear wheel cylinders, the lines were wet with fluid.
I took the master cylinder back thinking it was defective, bench bled the new one and installed, but still no fluid to the rear axle.
Is it possible that the proportioning valve is defective/bad? Can it be bled?

I haven't followed the line down as it runs to the rear of the truck (inside)
Possible line leak causing this?
Any suggestions would be appreciated, thanks.

 

[WTF]

Chances are your ABS sensor on the driver's side frame rail is clogged. You can replace it for around $120 or bypass it with a fitting. Did it on mine about a year ago and haven't had one issue.

 

[adsm08]

If the pedal stays firm then your lines are good. I'm thinking Dubbua there is right and it's your valve.

I've also seen plugged up bleeders do this, but you said you replaced pretty much everything, so I'm doubting that's the problem.

 

[larrybjr]

just had the same problem. did the complete brake job while doing the lift went to bleed the brakes and no fluid to the rear axle. went to my local scrap yard and found one for 10.00. Auto Zone wants 120.00 for a new one can get ya a part # if ya need one. But it did fix my problem. Now the valve is leaking but thats another problem. good luck.

 

[birddog321]

Mine had the same problem. Found a little block under the Driver's side door that was clogged. Cleaneed it out and everything was fine

 

[turboeeyore]

rear flex line may be collapsed as well

 

[rangercat]

Bumping for update....yep, turns out it was the ABS valve, was plugged up, bypassing fixed it, got rear brakes now and back in action
Thanks to everyone who replied

 

[PetesPonies]

So take your RABS apart and "refurbish" it. Theya re not diffuclt to disassemble and many times cleaning is all they need. I got mine to work correctly again.

 

[MYLILRANGER]

When you say ABS valve, are you referring to the proportioning valve?

I have the same problem with my 92 Ranger..

Thanks,
DG

 

[Sasquatch_Ryda]

When you say ABS valve, are you referring to the proportioning valve?

I have the same problem with my 92 Ranger..

Thanks,
DG

It is NOT a proportioning valve. It is the RABS Valve. It dumps the pressure going to your rear brakes to give you the RABS function that doesn't worth a shit anyways. Which is why I just bypass them on my trucks. No more worries....ever.

 

[PetesPonies]

no a Proportioning valve varies the pressure to the rear drum brakes on combo disc/drum systems. It takes more pressure to operate a disc caliper than does a brake wheel cylinder. Thus the pressure needs to be lower. The RABS controls the high pressure generated for the rear antilock system, totally different and is a seperate valve.