[mikes2]

When I bled mine, I pumped the pedal a few times while the pressure bleeder was pushing the fluid through. I kept a low pressure of about 5-8 psi.

Even after finishing, it was a few days before it was back to normal. It seemed to self bleed with use

You can use a Mityvac or similar to pull some through but you need a one way valve to stop air getting back in.

A last resort is to reverse bleed by pushing it through the slave up to the reservoir.