Im having some trouble with the brakes, the pedal just goes straight to the floor when you try to stop, but the thing is i have replaced almost every part of the brakes, replaced the drums and wheel cylinders, and the front discs and pads and a few lines, also it has a brand new master cylinder and a rebuilt proportioning valve. the brake booster is fine, its going to the floor because there is air in the lines, the right rear wheel just will not bleed, I tried 2 wheel cylinders but yet it still wont bleed, all of the other wheels are fine its just the right rear. any help would be greatly appreciated!

 

Start simple. Block the outlet ports on the master and see how the pedal feels. It should firm up very quickly and not bleed down. If it is still soft you have a problem in the master. If it feels ok, your problem is elsewhere.