Kitchenaid Impeller Replacement

Dishwasher would go through all cycles and drain. Circulation pump was making a slight humming noise and not move any water. Took apart the chopper assembly and found a piece of plastic jamming blades. Symptoms still persisted. Pulled sump out and found that threads inside impeller were stripped out. Ordered new impeller and seal kit and replaced. Ran first cycle, very loud humming, canceled cycle myself and machine drained. Checked chopper blades all clear and motor turns freely. Ran another cycle and still noisy. After third time motor hums, will not start and machine cancels. Any ideas?