The horizontally mounted motor on my 5 year old Whirlpool Model DP840 dishwasher has stopped running. The sprayer arm rotates freely when turned manually. The machine fills and the inlet control valve shuts off the water supply at what appears to be the correct point. The timer progresses through all the cycles but the motor never kicks in and the water never drains out. The motor body feels very warm to the touch, so it appears to be getting some voltage. Any ideas?