Hey, I got my brake system done on my truck tonight and I can't get any pedal. Especially when it's running, it goes straight to the floor. What I got is a disc/drum setup with a prop valve and an 8" booster. I bled the lines forever into a bottle with a hose on the bleeder so I could see any air. 3 of 4 wheels bleed perfect. The forth, a drum, always has a little air no matter what. It won't bleed at all. I have tightened everything several times, there's no drips or leaks anywhere in any of the lines. Cleaned and dried them all and they stay that way. I get a little pedal when it's not running but as soon as you start it and the booster gets vacuum the pedal just goes straight to the floor. I have tried this with the prop valve all the way open and all the way closed as well as half open. That makes no difference at all. Only thing I can figure is that the one wheel cylinder is sucking some air somehow. But I'm not sure that explains having zero pedal when it starts up. I'm kind of at a loss so any help would be appreciated.
Do you have a way to isolate that wheel cylinder? If it has it's own brake hose you can pinch that off to test it. If not you can find a flare plug to fit the T in the brake line. If the brakes then bleed and work on the rest of the system the source of the air is from the plug you put in the system out to the wheel cylinder. If you still have air entering the system it is farther upstream. Where is the master cylinder mounted in relation to the wheels? You might need to add residule valves.
Good idea, I'll try that tomorrow. It's a firewall mounted M/C. I read another post a minute ago, same problem basically and it ended up being a faulty M/C. The one I have is junkyard fodder so I may try that as well. I'll try what you mentioned first though.
Thats strange, the master is fucked up or somthing you can have one messed up in back and the fronts will still work, block off the messed up one at the tee and try that
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