Can't bleed air out of rear brakes

Okay... I bench bled the master cylinder and tried bleeding the rear calipers again. Same problem.

So, I started disconnecting things starting at my adjustable prop valve. When pumped, just a gurgle of fluid came out. I continued removing pieces up to the master cylinder port- just a gurgle of fluid comes out when the pedal is pushed. Should be a solid stream- so I just ordered another master cylinder.

Hopefully this will be a good one.

Thanks for everyone's input.