Quote:
Originally Posted by dsraven
brdog, that is the same basic principle as the one man bleeder mentioned earlier here. the difference is that the one man bleeder uses a seperate container because it can be placed close to the bleed screw.
brake fluid is like paint remover so being close to the source is a good thing plus the length of hose from the bleed screw to the master cylinder could cause other issues like low spots that can trap air or the weight of the hose pulling the hose off the screw.
if you are not familiar with a one man bleeder, it is a small container which gets partially filled with fresh brake fluid. enough to cover a hose that is set down into the bottom of the container. the other end of the hose is connected to the bleeder screw and the bleeder screw is opened. the theory is that gravity will usually want to push fluid out the bleeder screw so there is less concern about air getting in from the screw being left open. when the "one man" steps on the brake pedal fluid/air in the system is forced out the bleeder and down the hose. this is when the second man would normally close the bleeder screw so when the pedal is released no air can get back into the system and also so the master cylinder can refill from the reservoir when the pedal is returned to normal height. with a one man bleeder the screw is left open and any air that would normally be allowed to be sucked back up the hose from that bottle will now be full of brake fluid because the end of the hose is sitting in fluid. it may take a few strokes of the pedal to get rid of the air initially in the hose but this system works well. one thing I learned right away is to not open the bleed screws too far because air can get past the threads of the bleeder screw and mess up the whole theory of operation. however, I use it all the time. when replacing calipers/wheel cylinders or on a fresh system it would be a good idea to take some time and fill the master then open the bleeder screws and allow gravity to assist you in filling the system, just to cut down on the number of pedal applications it takes to fill the system initially. on systems with the pedal below the floor a pressure bleeder would be the best idea if one is available and could be fit into the space under the cab. this is because there is not enough difference in height between the master and the wheel cylinders or calipers.
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What you say makes perfect sense and I know what you mean about brake fluid on paint - been there, done that. Without a return line to the reservoir, you just have to keep an eye on it so it doesn't run dry during bleeding. Thanks for the tips.