We did bleed the MC till it was incredibly hard to push in.
We tested it again by taking it off and caping the front bowl and leaving the rear off. Fluid seemed to barely spit out the back, but if you put your finger over it, after about 3 pumps it would push your finger off and spray a little bit more fluid.
We added about 6 feet of line and I'm wondering if there is just so much empty line that no pressure can build up?