I agree with Don, adjust the brake shoes. If they are too far away from the drum it takes more fluid than can be pumped out in one push to make contact, hence you have to double pump. Make sure the MC is full of fluid or you will pump air into the lines which can cause the same feeling in the pedal.
To test the Hydrovac's put your foot on the brake pedal with medium foot pressure and then start the engine...as the engine builds vacuum you will feel the brake pedal fade just a little bit if they are working. If you try this after just having the engine running you'll need to pump the pedal 6 or 8 times with the engine off to bled off the vacuum reserve tank...
Hope this helps,
Mike B
