My main motor seemed to be seized up. I've removed the dishwasher, taken out the sump, removed the locking bolt from the motor assembly, rotated the lock collar for the motor, and can't seem to get the motor/pump assebly to pull out of the sump. Is there some trick to getting it out, or should I just pull harder? It feels like there is some sort of lock ring or something causing it to bind up. Any help would be greatly appreciated. I want to remove everything, inspect the pump and impeller, and replace the motor if necessary.