Bigdonn,
There is a seal in the hydrovac, that if it fails, brake fluid will go into the vacuum chamber. You have to fill up the chamber before you start sucking brake fluid into the intake manifold. That chamber is pretty big and will hold several refills of your master cylinder resevoir. Thus, it becomes a "black box" for brake fluid, making you wonder where it's going. The key is watch your master cylinder resevoir level and if it gradually drops, without any external leaks, that is likely your problem.
I would be checking the hydrovac, before tearing into the master cylinder. And yes, you probably sucked air into your lines, and you need to bleed your entire system. How do I know all this? Been there!
Kent
