Quote:
"should I start with another bench bleed or use the pedal and do a two man conventional bleed? I am thinking maybe the vacuum bleed moves the fluid so slowly it doesn't capture bubbles trapped in high points."
1P2M, what is your opinion on this? I also bleed my brakes with a hand vacuum pump but after I'm done I will usually get my wife out to pump the brakes and finish bleeding one more time.
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I don't vacuum bleed very often anymore. I don't really believe that vacuum moves air too slowly to push air out. Gravity bleeding can be successful even if it takes a while. But I have had unexpected problems with vacuum such as air being drawn past wheel cylinder cups or past the master cylinder piston. And I have had the same problem with air being drawn past bleeder threads that others have mentioned. Those problems almost never happen with gravity or gravity plus pressure.
An old fashioned manual bleed seems to be the best way to get the job done when a pressure bleeder isn't available. Saving time by using vacuum as the first part of a two step process seems to be a reasonable compromise.
Sometimes I use a 1 man bleed process. It can be tough to get someone else to describe what's happening with the pedal when you're having trouble getting one. I pump up the brakes 4-5 times, prop a hood support rod between the seat or dash and brake pedal, then hop out and crack a bleeder. I can see if air is coming out, if fluid is restricted, or if there's some unexpected problem. I can also feel the brake pedal to see if it gets better as air is removed. I think it makes it easier to catch a problem.