I believe Joe has a correct master with bleeder screws. Although in theory these are far easier to bench bleed, I still like using the screw in barbs and hoses to remove air from the master. Then I can visually confirm that no bubbles are escaping from the fluid. If you have very snug fitting tubing you can do the same with the bleeder screws, and not disconnect the brake lines again.

The whole point is that his master was fine until he tried to bleed the front lines. I think the root of his problem is air in the master cylinder and the lines, not a suddenly and coincidentally failed master cylinder.

Here's why:

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">So, Dennis comes over, we bleed the master, that didn’t work. While pumping up the brakes we find that my rear line at the block by the master cyl. was loose and introducing air into the system.
OK, tightened that up and continued the to bleed the rear brakes. After a while of manual break bleeding the rear brakes were pumping up really nice with no air coming out. Nice solid peddle.
At this point, we moved to do the front brakes just for good measure. The fronts were never opened at all and the car always broke well.
This is where things went bad.
I pump up the brakes, then Dennis cracks the bleed on the front pass side. OK, no problem. When I go to pump up the brakes again, they are really soft as if there was a whole bunch of air in it??? The fluid is also very foamy.
</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">After air was known to have been introduced into the system, the master was not re-bled.