master cyl ??????

well i was off today and got my brake lines all figured out on my t bucket frame thought i would bleed the brakes using a manual master cyl from 73 nova got a rebuilt one.
started trying to bleed brakes but master doing funny things seems to take the fluid from the front tank and pushing it out the rear outlet is this right?? doesnt seem right to me i think maybe faulty master cyl as when i attempt to bleed the front brkes also tries to take out of front tank not rear.
drums on front and rear of car.
any ideas from anyone??/