Thanks,
I did manufacture a pressure bleeder from an ACE 1 gallon sprayer. I added a fitting and a regulator to the side so that I could run it from an air compressor and keep constant pressure on it. We also manufactured an adapter to fit the resivoir, it has a bleed screw and extends up into to cab for easy access. This system seems to work great.
But...
I still have something going on. This system is all new/rebuilt. We have the wheel cylinders rebuilt to new condition, the Hydrovac is rebuilt to new condition, and the master cylinder is rebuilt. We also have 100% new brake lines installed. The system is fully bleed and adjusted and still the pedal goes almost to the floor. It works quite well if you pump it once or twice. It's almost as if there is not enough fluid to fill the pistons. I have the master cylinder that every auto store says I need, it is a 1 1/4 inch bore. Everything appears to be right according to the Chevy service manual. If I cap it so that I dead head the unit it works fantastic, hard as a rock with no fad, so there is no bleed by on the primary cup. The only thing left in the unit is the check valve and I have no good way to test that, although I don't really see how that would affect the outgoing oil as it is there to control the return oil.
The manual says after bleeding and adjustment with 75 pounds of force on the pedal there should be 5 inches of clearance from the bottom of the pedal to the toe board (with no mat).
I've ruled out air in the system by adjusting the pads all the way out until they can't go any further, this results in a very hard pedal with no mush or fad. As I bring the pads back into proper adjustment I continue to loose toe board clearance until finally I need to pump it for good operation. Also when the unit is fully pumped up I can only get about 4 inches of toe board clearance instead of the 5 the Chevy service manual says I should achieve. I could live with the 4 inches if it were there when the pads were adjusted properly.
As a second question, I seem to have a discussion going with some others here as to how much drag is proper on the wheels. I have never had any problems with being able to barely hear the pads wisping the drums but another says I should leave them at a point that will make the drums hot with just a drive around the block. I know that "lite drag" is subjective but is there any better methods or thoughts on this.
Thanks again for the feedback.
