first question i have to ask is, did the pedal pump up? if so then when you cracked open the bleed screw, did the pedal then go to the floor? third question is how much pedal travel was there from being pumped up to being on the floor.
its possible that you have a large air bubble in the line somewhere, probably just beyond the connection to the master cylinder.
so what i would do is, have your son pump up the pedal, and then crack one of the line fittings at the master cylinder and see what happens. if you get fluid from the line, then the issue is down stream, if not then the maser cylinder was not properly bled.
another thing you can try is fill a clear bottle with fresh brake fluid, and on the rear most brake, use a clear hose attached to the bleeder with the end in the bottle down in the fluid. then with the bleed screw open, have you son pump the brake pedal like he would in normal braking. if you see either fluid coming out, or being sucked up, that means you have a clear shot and you just need to be patient. if nothing happens, then you have a clogged bleed screw, line or something causing an issue. at that point i would pull the wheel cylinder off and pull it apart and see what is going on inside.
05 grand marquis
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