Dishwasher was functional but motor sound became progressively louder until one day would not run. When started, the tub fills normally. When full, the motor runs in 1-2 second loud bursts. I think I can hear faint sounds of water circulation during the bursts. Through the motor windings I can see a white shaft that spins when the motor starts. When I removed the lower wash arm, there was some broken glass found and there is impacted food in some areas of the large round assembly upon which the arm is mounted ? this is pump or impeller? What are most likely problem/problems? when cycle is cancelled, the tube drains normally and dishwasher shuts doen normally. Thanks for any assistance you could afford.