Pedal goes to the floor... And i am stumped

Hi,

On the master cylinder, just because it's new doesn't mean it's good especially if it's a remanufactured unit. I doubt you would see a hose balloon out , they are pretty thick internally. How did you bleed the brakes? You still may have air in there.

Also, are the rear brakes adjusted properly. They need to be adjusted all the way up or you will get a low pedal.