I connected the motor to a 14v battery and it runs but when I connect it
directly to the power supply (red and blue wires) it just hums (quietly). I
measured 100vdc from the red/blue leads on the power supply. Could the PS
not be generating enough amperage to magnetize the armature? How can I test
this without an ammeter?

Here is a picture of the PS:
http://www3.telus.net/martik/motor1.jpg