well the set up got held back a bit because i need a capacitor to make this motor work and someone came into my brothers yard and stole the remains of the washer that had the capacitor on it. In short if you try to use the method of the pump and motor try to make sure your motor is a simple two wire type. I have been told to look on old dryers and big shop fans for one of these.
I know this thread is pretty old, so I'm not sure if you ever got your motor/pump working. I am in the process of setting up a WMO centrifuge using the modified SBC pump and a washing machine motor, 115v 6A 1750RPM.
My motor, like yours would only hum when wired up POS, NEU, GND. I had an electrical engineer I know look at the wiring diagram, he discovered that the motor had a built in start capacitor. In my case, all I had to do was connect the red(start cap) wire to the black (pos) wire and the brown(who knows) wire to the white(neutral)wire. Now it fires right up, no humming or needing to start the motor by hand.
Just a word for the wise, I blew a GFCI outlet trying to figure out which wire was the start wire
I still need to modify my sbc pump and figure out how to attach the two.