also does not explain why i don't seem to be able to bleed the brakes now. i will check the wheel cylinders , it is my only guess now- leaky wheel cylinder.
Am I understanding you correctly...with a full MC you can't get any fluid to come out of the bleeders. Even if the wheel cylinders are leaking, you should still get fluid out of them when you open the bleeder valve.
Are your brake lines all new or recently replaced (steel and rubber)?
As you said, it's time to pull all four drums and inspect for leaks...