Maybe one of you can help me out. I took a 15 mi test drive yesterday and when I got back home my (Huck) brakes were smoking hot - all four wheels. I discovered that I have a posi-traction rear end as both the rear tires dug into the gravel a couple of inches as the front brakes actually locked up tight preventing me from moving forward. I let everything cool down for about 90 min and jacked up the front to back off the adjustment, but to my surprise both front wheels were freely turning, not a whisper of a shoe touching??? I drove it easily into the garage and had normal braking. I have been seating the new shoes and adjusting the rear cyclinders and the e-brake, testing them over the 30 mi total since the rebuild. It's as if the brakes aren't releasing - as I'm writing this I wonder if I just need to make a pedal adjustment ?
Make sure there is a slight amount of slop between the master cylinder and the rod that activates it when your foot is off of the brake pedal.
Hey Larry, A hard lesson learned for me was that I had replaced everything but the flex hoses and had a right front that would lock up. I did as you describe to no avail. Once I replaced the flex hose the problem was fixed. Apparently, even though they may look fine from the outside, they become weak. Once this happens the pressure from the master cylinder upon braking will expand them and allow the shoes to brake but the back pressure from the wheel cylinder is not great enough to return the fluid to the system. In essence you have a check valve. I hope this helps. Gater
Hi Larry I had one do this to me. I found a wheel bearing that had 1 bad ball in it. If it was down when the stop was made it acted like the brake was on. If you have ball bearings they need inspecting and repacking often.
I installed new hoses with new cyclinders, shoes and lines. Also installed and packed new front wheel bearings, one side had a bad raceway and bearings. I will check for play in the pedal, but curious why it corrected itself when it cooled down.
Did you rebuild the master cylinder? You might have a blockage there that would cause the brakes to drag.
New master cyclinder - all new total brake system. Everything was pretty rusted up, as even in a garage in San Francisco the damp sea air replaced all brake fluid with a nice crusty, rusty, pitted mess and I knew I wanted to be able to rely on stopping...
My first thought was the same, there is not enough clearance between the master cylinder and the rod from the pedal. As the truck is driven, the heat can cause the pushrod to slightly depress the master cylinder piston and cause the brakes to drag. It is worth checking. I have seen it before, and it can stop as it cools down. If that isn't it, you may have to try to see which wheel, or wheels are dragging, and try to isolate where pressure may be not releasing. Good luck, hope it's simple.....Mike
That's It ! What Mike said ~ if there's only a bare little bit of clearance , or if the brake pedal return spring is weak or gone missing , the brakes will pressurize over a time until they heat up and lock solid , usually all four wheels . I like to reach up and rattle the M/C pushrod by hand as having the least amount of play that you can , will increase the pedals travel , always a good thing on older rigs . A tip : there's another brand of vehicle , begins with 'F' and they made a " Model A" and one of the original Fulton acessories for it , is a nifty hook and spring deal that loops over the pedal arm and then a long spring attaches and it serves to fully raise the brake (or clutch) to where it hits the toe board with a thump every time you release it... Cost is like $10.00 and I don't know why old Chevy parthaus' don't cary them too as we can benifit from Brand F's poor design
Just as Nate, Mike and I thought, when I checked the pedal adjustment last night - no play. I'm pretty sure I checked it when I had the engine out, and installed the new MC and brake lines, but there definately isn't any play in it now atall. The return spring pops the pedal right back and it didn't present itself as a problem until I went on a longer test drive. Thanks everyone for their input.
No Worries ! Not only Huck brakes do that , I've had a few Bendix & ATE equipped cars lock up after a major brake overhaul in the last 40 years ... Setting the M/C push rod ' Just So ' is an aquired thing You're prolly good to go now , remember to break in the brakes gently with lots of full stops rather than slowing way down then going again , plan to re-adjust the brake shoes a few times as they bed in and the pedal sinks a bit. Remember : TWO adjusters per wheel ! .
