Spa pump motor shaft seals – they are meant to keep the water from leaking along the shaft of the pump motor, behind the impeller. When a shaft seal fails, as they do from time to time, you will notice water dripping along the backside of the volute (where the shaft enters the impeller housing), running down and dripping off the bottom of the pump.
A leaking shaft seal can easily be confused with a failed volute (impeller housing) o-ring, or with a leaking union or plumbing fitting on top of the pump. In fact, many leaks around the pump will end up running down – and dripping off the bottom.
U.S. Seal PS-1000 Standard Grade General Service Pool - Hot Tub Pump Shaft Seal Assembly.
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