Still laying in bed laptopping. I know...LAZY. One of the retirement perks. Going to be the last of the nice, warm, sunny days for a while here in the North Pole. Then snow later this week. Bah. Old backup pump is already set up to externally circulate water, and I like to play with water. Me feels an experiment happening a little later with suction side blockage. MAS may be on to something with the impeller but I doubt bad bearings would cause this. With enough drag on the motor to heat it up, the bearings would grind up real quick and you would need hearing protection.
Al