Duane: If you bleed brakes with clear tubing (tygon tubing) and open up the bleening valve several turns, you will see air entering the system through the threads of the bleeding screw as the brake pedal is allowed to return. That is why I suggested turning the valve just enough to allow the fluid to escape. This allows no or a minimal amount of bubbles into the area next to the bleeding valve. With a lot of air next to the bleeding valve, there is the possibility for air to get back into the wheel cylinder. The procedure that I recommended specified pumping the brakes to clear the line then holding the brake pedal down with a stick wedged against the steering wheel and the brake pedal. Fluid or air will not back flush into the system when the brake pedal is held in the down position. I they check to make sure the fluid is clear (new fluid being expelled and the system flushed). If it is not, I continue with several more pushed on the brake pedal. If the fluid is clear, I tighten the bleeding valve then release the brake pedal by removing the stick. I might add that I do extend the bleeding tube into a container that has brake fluid in it as you suggest.
I am not suggesting gravity bleeding is bad. In fact, it may be the best method. I am impatient and do not want to wait that long for the system to slowly bleed by gravity. Likewise, pumping (sucking) the fluid out of the wheel cylinders would be an excellent method. I do not want to buy a pump just to bleed my brakes every two years.
Thanks for your suggestions and comments!:bigsmile: