Hey all, I bought a 75 Cordoba a couple months ago, and realized that I was getting squishy brakes. Turns out, I was losing fluid out of the Master Cylinder. There was a new one that came with the car, so I installed it. I went to bleed the brakes, but I was getting no pressure at all and noticed a loud hissing noise when I pressed the pedal to the floor. Is something not sealed right? Any ideas would be appreciated. Thanks!