Help! Front brakes keep going out!

[flyboy2610]

That's the distribution block for the brake lines.

[fordman]

thats the porpotioning valve which is suppose to equalize the fuild to all four wheels. that is what i was told. did they really give you new hubs shoes and cylinders on that wheel? did you check to make sure they did? or did they just put the wheel cylinder back together? when using a mechanic they have to give you all the old parts back if you want them. at least thats the way it was in california. the dealership was required by law to give the customer the parts back if they asked for them back. give us a pic of the situation including the drum then we could probably help you better.

[67F250CS]

Hoses starting to colapse?? In theory the pressure of the fluid is enough to push the fluid toward the cylinder but when you release it cant return to the Master fast enough and is building pressure every time you brake and causing the blow-outs. How is the route to work lots of stop and go or highway cruising?

Again just a guess but Im leaning to the hoses.

[russtay66]

So...does the proportioning valve work automatically, or do you have to adjust anything on it?

I just asked my wife about the cylinders being replaced (she's the manager at the shop where the work was done) and she said they thought there was nothing wrong with them because there was no fluid on them when they took the drums off. I had driven the truck for a couple weeks with the front brakes not working, so there probably wouldn't have been.

I'm going to try one more wheel cylinder tomorrow to replace the one on that right front wheel. We'll see if that works now that the other parts are ok.

Thanks again.

Russ

[russtay66]

The hoses are new. I go to and from work in typical suburban Dallas traffic. Some stop and go but not too bad.

Is it possible the hard lines are collapsed?

But it worked for many weeks until the drums were turned, and now they didn't replace the wheel cylinder, so I'm still thinking if I replace the wheel cylinder again, that might do it. We'll see. I'll keep posted.

Russ

[fordman]

no. no adjustment as far as i know for that valve.

[67F250CS]

It might be that " Bad batch of parts syndrome " that we all have dealt with from time to time. Once had 3 alternators from NAP@ in the same week!!
Man I hope you figure this out soon.

[FORDification]

Vehicles with four-wheel-drum brake only have a distribution block, they don't use a proportioning valve. The prop valve is only used on drum/disc and disc/disc vehicles....unless you add one yourself. There's no adjustment to a distribution block, aside from recentering the electrical valve in there which acutates the warning light on the dash in case of brake failure.

I don't know how hoses, however bad, would cause a brake cylinder to fail. I'd have to agree that it sounds like they reused the same cylinder(s) and that's what's causing your problems. Let us know how this turns out.

[russtay66]

So far so good with the new replacement front right wheel cylinder, But...I've not driven it very much since I put it on. I ride my 2-wheel transport to and from work most days anyway.

Hopefully that has fixed it.

Thanks for everyone's help and support.

Russ