Rear brakes and master cylinder dry - Bleeding?

[Buick_T]

I have a problem (again). My Mirada with front disc / rear drum brakes had rear axle removed and brake lines re-done. In the process I (by forgetting to block) ended up draining a major amount of the rear brake hydraulic system.

I added brake fluid to the empty container of the master cylinder and we tried to bleed the brakes. No air seems to come out from the rear cylinders anymore but the pedal still goes to floor when all bleeder valves are closed and can't properly do the "pressure-open-floor-close" procedure. Pumping the pedal does not exactly help, the pedal is not exactly soft but not firm either. I can just steadily push it to floor...

So, there might still be air in the lines, just bleed and bleed and bleed again? Or is there air in the master cylinder..?

And can I bleed it without removing the cylinder for bench bleed process?

I should be getting my car to other side of town in a week or two, still missing brakes, the car runs rough, is missing tail-shaft seal and all kinds of other stuff to tackle..

 

[Aspen500]

Start by bench bleeding the master. You can do it on the car. If you put plugs in the outlet ports, you can slowly pump the pedal until it is firm and hook the lines up again. Then try bleeding at the wheel cylinders again. Sometimes the proportioning valve can get stuck after rear hydraulic failure and block fluid to the rear. There's a stem sticking out of the valve to reset it. I'll be darned if I can't remember if you pull or push it right now. Must be getting old, lol.