The Stovebolt Site Forums The Shop Area Driveline 1956 3100 brake problems !! X-cali prerunner

Ok so here goes nothing ! I just bought this 1956 Chevy 3100 it has about 4-6in of lift an 8 lug Dana 60 in the rear and a stock 8 lug straight Axel up front with 285/75r16 on it looks cool every one swears its a 4x4 but anyways the guy i got it from had just put a power brake booster on it , and told me the pads just needed adjusted well i did that and had all the drums turned replaced both front wheel cylinders and still have little to no brakes ! The vacuum is hooked up to the intake like all Chevy v8s i have had , i have bleed them 2 with a phoenix bleeder and still nothing ! Now i dont have a proportioning valve in it , but doe sit need one ?? O ya and also it seems to only have brakes on the right rear ?? iam stumped never had to deal with power drums !

Hy oldsoul-65, if your truck has drums all the way around, then no proportioning valve is required. Are you sure the brakes are all adjusted up correctly? Was a drum brake master cylinder used? If a disc brake master cylinder was used, then you must install a residual pressure [10 p.s.i.] valve in the line to the front and the rear brakes. Will the brakes "pump up", that is will the pedal come up, and get harder if you pump the brakes?

Thanks for the reply !! Iam pretty shure the brakes are adjusted right . I dont no what kind of power brake booster it is ? it all looks new, like it came in a kit. Is there any way to tell if its for drums or disks?? And no the brakes do not change with the engine running or off , and i pumped tell my leg fell off both ways with little to no change. All the after market brake booster kits i have seen all have a proportioning valve right under the master cylinder but not mine ! Dont know if it matters or not but this is a stock location set up , still under the floor .

Hy oldsoul-65, you will have to find out what kit or parts were purchased, there is no way to tell, that I know of from the outside whether you have a drum/drum, disc/disc, or disc/drum master cylinder. You said you have bled the system till the cows came home, so you should have all the air out. Drum brake systems must have residual pressure valves, either built into the master cylinder, or added as inline valves. Have the three flex lines on the truck been replaced, they may be causing some of your problems, if they are collapsing from the inside. It may be the best idea to take the master cylinder off and dissassemble it to see what you have. then you can reassemble it, bench bleed it, to make sure both primary and secondary systems are functioning correctly, then reinstall and rebleed the system, good luck