Bad brakes!!

in a stock 62' chevy c15, why the hell do my brakes lock up when ever i so much as get warm? Its at the point i cant drive it,
i need this truck to run and drive good, i want to get a disk brake kit but thats going to have to wait, any ideas how to fix or what to do?
i have all new shoes im going to install this weeked and i did have this problem on a vw bus, it was the rubber hoses could it be the same problems

 

The main cause for this is usually that the piston in the master cylinder is somehow being prevented from fully retracting and is blocking the return hole, allowing the brake system to build pressure with heat from the exhaust,etc. Try checking the pushrod to see whether or not it has a slight bit of play when the pedal is up. If it has a lot of play, the piston itself may be sticking. If there is no play, it may need adjustment.

 

Don't mess around, rebuild/replace the whole system. If one part is going bad, others can't be too far behind. Look into a master cylinder upgrade. When you decide to add discs, you can then swap in a proper master for them too.

 

Old flex lines will do that as well. When they begin to separate, brake fluid under pressure gets in between the plys, and collapses lumen as it also moves the piston. When you let off the brake pedal, there's so much pressure inside the hose, the lumen stays collapsed, fluid can't return to the mc, and your brakes stay engaged. (Ask me how I know this.)

You need to rebuild the entire system. Master, all wheel cyls, and replace all the lines.

 

Yeah, first off replace the flex hoses & bleed the system, it's the cheapest & quickest thing to knock off the list of probable causes. If that fixes it, cool. If not, go into the MC, wheel cyl, shoes, springs, etc. Good Luck.

 

Do you have brake pedal freeplay?

There should be about a half inch between pedal mechanical top-out and where it starts pushing fluid.

If no free-play you can have pressure constantly applied.

If the shoes are adjusted up close and get hot, there's your lock-up prob.

 

well the pedal is nice and stiff, not too hard, but i do think its the hoses, it makes the most logical sence, the shoes might need to come out too, thanks all,

what about with disks, do i need to change the master? im pretty sure i do.

 

We had a car that had a brake pedal bumper on the up swing. The bumper got adjusted wrong the bumpewer held the brake light switch. So it never returned 100% and the system just kept on building pressure every time you used the pedal till you had a lock up situation. We would park the car for a half hour or so then it was fine. Then happen all over again as soon as you started useing the brakes

 

whats a bumbper ive never delt with one
my trucks outside but im the only one at my job(awsome job that i can do this lol) but i cant go out to look at it

 

Yea you'll have to change the master for discs. Easy to do. I personally drove the ever loving shit out of my '64 C-10 SWB that had a mild SBC with stock drums. 80+mph everywhere, in town, in traffic, long trips...It stopped fine. My dad's '64 C-10 LWB gets driven ALOT, again with a stout SBC and stock brakes, no problems there. And my brother's '66 C-10 LWB with a brutal SBC and stock brakes does just fine. It's personal preference, I'm sure they want to do a disc upgrade, I wanted to as well on my '64, but hey it stopped fine, so no reason to fix what ain't broke. I personally like the feel of drum brakes, maybe it's nostalgia, maybe it's stupidity?

Good luck on your issue.


Edit: "bumper" is a rubber stopper to keep the pedal from clanging around in the upright position. Your truck doesn't have one, so don't worry about it

 

oh ok,
yea well my truck actually sucks at stoping lol
whats sbc?
my truck is real hard to stop i dont know why becuase its not that heavy,

i could be out of adjustment maybey becuase i know its bled otherwise i would feel the give in the predal,