Impeller replacement went well. The impeller vanes had separated from the plate that threads onto the motor shaft. That why I was feeling a good connection from the impeller to the motor. It just wasn't connected to the vanes.
Now for new problem. After a test cycle the dishwasher just keeps filling, even when it is off. I would immediately suspect the fill solenoid. But wow thats a coincidence that that would go out within one wash cycle of changing the impeller. I took it out, tests at 1000 Ω can't blow through it, tested the two micro switches on the left hand fill assembly manifold thingy both test good on both poles. all the linkages seem clear and functioning to the micro switches. Blew on the diaphragm actuator that engages and disengages the micro switch fine. Anything I missed before changing the solenoid?