The Stovebolt Site Forums The Shop Area Driveline brake failure - what's the cause

some of you are going to beat me up on "checking the search feature" first, but I did that and not a lot of help.

Brake pedal went to the floor 2 days ago. The culprit was obvious - or at least I thought it was - as the driver rear wheel cylinder appeared to be leaking. Replaced / repaired with kit...no big deal there. Brake fluid level was low also (no surprise, as much of the fluid was on the inside of my tire). After repair, bled the brakes, fartherest to nearest the MC. Guess what. NO leak is seen now, but STILL NO BRAKES. Front left wheel catching only. Pedal goes to floor. Filled reservoir. Should I re-bleed again? Pedal doesn't fill like air. THe MC is a single reservoir and is 5 yrs old (4,000 miles, maybe). How can I tell if the MC is bad? Should I re-adjust all brakes? why is the front driver catching but nothing else. Brakes were decent before all this. sorry so long.....just trying to put all the info our there. any help appreciated.

Sounds like a bad MC. When you bled the brakes did the fluid squirt out with any pressure?

If you adjust the brakes so the wheels will only turn 3/4 of a turn when spun by hand and then bleed the brakes until no air comes out the only other thing I can think of is the MC. But I am sure others who know more will correct me if I am wrong.

Rich

try taking the line looseat rear end not off then pump and tighten line back up you still have air

Moving to General Truck Talk- you'll get more answers there.

Put a kit in the master cyl. When they sit around the fluid gets cruddy & when the pedal goes down further then it has been the parts get in all that corrosion. Bench bleed the master cyl before you put it on. Speedy bleeders would help in a situation like this.

Today I found that the adjuster was completely loose on the front pass side. My only conclusion is that this alowed the shoes to press uncontrollably. I pulled the hub, re-installed the adjusteer at the bottom , adjusted fronts and rear, and now I've got some real pedal....stilll some air in there. I hope to get the wife to help me to bleed, and then shoudl be ready to go. I am still worried because of the earlier question - I have an old style single reservoir....should I switch, and if so, to what.????? My truck is a '53 half ton.

I don't like messing with brakes that are questionable. If it was my truck, I would do what I just did to my truck. I would install a new dual reservoir master cylinder from someone like Master Power Brakes (http://www.mpbrakes.com/). They can set them up with the lines exiting either side and with a kit, which are avilable from several of the vendors, you can mount it under the floor, like your current one. Then I would get four new wheel cylinders and four sets of new shoes and I would even consider running new lines, especially if your have any rust on them. When I finished the job, I would know I could stop which is almost more important then being able to go! When buying the wheel cylinders, I would try my local INDEPENDENT parts store first. Many of us have found out that new wheel cylinders for these old truck are still plentiful.

Joe

Yeah, convert to a dual reservoir for sure. I drove my '62 for a year and several months with a completely rebuilt single reservoir system, and I was edgy every single time I depressed the brakes. It took so long to convert, because I have the hydraulic clutch, which almost doubled the cost of the kit. Not pleasant, but worth it.
I have a '54 Buick I drove daily for a year and a half some time back. I blew a rear wheel cylinder on the way into work one morning. To make a short story long, if I hadn't gone into work really early that day, I'd have probably been killed because the intersection the brakes failed at was steady semi truck traffic between I-4 and the main warehouse complex for Publix grocery stores. From 8am until 8pm, it's non-stop. I came to a stop in the far lane, even after down shifting and putting all 220 pounds on the emergency brake.
With a single reservoir, when you blow one line, all the brakes go. When you blow a rear, inside the drum, your park brake won't catch on that side. I can tell you for a fact that one brake drum will not stop a '54 Buick traveling at 40mph.
Every time I drove the Suburban, I looked for an escape route every time I pressed the brakes. That's a real pain, considering I drove it 20,000 miles last year.
Buy the dual reservoir and new lines.

-Brad