I'm trying to bleed the brakes on my deuce hiboy build without much success. I'm using an under-floor mounted Corvette master cylinder, Wilwood 10 psi Residual Pressure Valves on front and rear lines near the MC, self-adjusting drum brakes all around. After tightening and fixing the few leaks, I started bleeding the brakes the traditional way with an assistant pumping the pedal while I watched for bubbles at each wheel cylinder. We never really got a good firm pedal. I then tried a vacuum brake bleeding kit with results that are strange to me. I can draw 24 in. Hg. on the vacuum gauge but very little air or fluid is drawn out of the wheel cylinders. It seems like something is preventing the fluid/air mix from exiting the wheel cylinder. Master cylinder top cap on or off, it doesn't matter. Crappy pedal or no pedal at all. I'm beginning to think that the problem may be with the two residual pressure valves. Has anyone had experience with these valves giving problems? Does anyone have experience with these vacuum brake bleeding sets from Speedway?