So I'm trying to get my 54 Dodge Royal rolling. After completely rebuilding the master and bench bleeding it, I got it installed and began to bleed my brakes. The power bleeder wasn't working so well, so a friend and I resorted to the two man method. Once we started doing that, we noticed that the piston wasn't returning as fast as it should. So the other day I drained everything back down so I could pull it out again. Just for fun, I pumped the brakes dry to see what would happen. Works awesome. Pulled it anyways and put it in the vise on the bench last night. Now...I'm no brake guy, But I tried a few things that made sense to try and "test" it. With my hand covering the fill hole, it creates quite a bit of suction and hold a vacuum. I put fluid in it on the bench, and it pumped fine. Once I put pressure/restriction on the outlet, the piston slowed down once again. After that, even without any restriction on the outlet, the piston still moved extremely slow. Drained the fluid, and it works fine again. Now it's completely torn apart again, and I'm stuck scratching my head. Thoughts?