Dishwasher was not pumping water forcefully. Impeller appeared to be busted. Dishwasher is 20 years old, so I replaced the entire motor assembly, which includes the impeller. Labeled all wires before removing and replaced wires on same terminals as old motor. Now when I turn the washer on, the only noise is a hum from the large capacitor attached to the motor assembly.

What could be wrong--wiring? etc.