yeah, the new slaves come pre-bled as a 1 piece unit with the master cylinder.
If yours is a bleedable unit, there is a bleeder screw in the slave just in front of where the line hooks to it. looks just like the bleeder on your brakes with a nipple on the end of it. if no bleeder, you get to spend the 250 bucks to get a new master and slave combo, but that is where your problem is....air in the system.
sometimes you can cheat by reverse bleeding the unit...make sure the master is full, take the slave out of the bell housing, and compress the rod as far as it will go, wait a few minutes, and pull the rod slowly back out. then repeat as many times as it takes till you dont see anymore air bubbles coming up into the master cylinder cup.