Humming Pool Pump

[ozone78]

Pool owner since 1992. 20,000 gallon vinyl liner. Hayward super pump with AO Smith motor (C48J2N131B1). Just opened pool and everything ran fine. Turned off pool to hook up vac hose and when I turned it back on I got the dreaded pump HUM. Replaced the start capacitor and still had the hum. Went back to pool store and got a second capacitor, same outcome. Used power drill to spin the impeller and the pump runs. Impeller turns freely and there is no noise that would indicate bad bearings. What am I missing here? Not looking to replace the motor if I can help it. Thanks for any input to solve this issue.

 

[mas985]

Pool owner since 1992. 20,000 gallon vinyl liner. Hayward super pump with AO Smith motor (C48J2N131B1). Just opened pool and everything ran fine. Turned off pool to hook up vac hose and when I turned it back on I got the dreaded pump HUM. Replaced the start capacitor and still had the hum. Went back to pool store and got a second capacitor, same outcome. Used power drill to spin the impeller and the pump runs. Impeller turns freely and there is no noise that would indicate bad bearings. What am I missing here? Not looking to replace the motor if I can help it. Thanks for any input to solve this issue.

Does the pump motor have a centrifugal switch in the back? Sometimes the contacts can corrode preventing it from starting.

 

[ozone78]

Didn't have a centrifugal switch but your mention of corroded contacts set me on the right path. Took apart every connection I could find and sanded every surface I could get at. Flipped the switch and I'm back in the pool business (which is a lovely shade of green due to two days of no filter with temps in the high 80s...) Many thanks for the advice!