The air is coming in between the threads of the bleeder screws. Very few people use vacuum bleeders. I have the best luck simply letting the brakes gravity-bleed. Leave a small gap open on the reservoir cap so it doesn't build vacuum that prevents the fluid from flowing. When fluid drips from one bleeder, snug it and wait for the next one to flow. When they're all bled, irritate the brake pedal a few times by hand, open each bleeder once more for a few seconds, tighten them and you're done.
The calipers won't cause the brake pedal to sink to the floor. When it comes to replacing the master cylinder, there is a simple trick that eliminates the need to bleed at the wheels. The disadvantage to that is you don't remove the old moisture-laden brake fluid.
Sunday, September 18th, 2011 AT 9:23 PM