I recently purchased a 1989 Chevy C/K 1500, 4x4, lifted, etc. The brake pedal will press all the way to the floor before it starts actually working, I noticed the master cylinder o-rings were leaking so I replaced it.

Now my predicament, I am trying to figure out of the new master cylinder is defective. When you press the pedal after priming the master and bleeding the brakes, it will shoot fluid upwards inside the reservoir like a fountain, when you press the brakes! I have never seen this before. What in the world is the deal here?

That's totally normal. For some strange reason it will do that. How is the pedal feel now?