The problem that brought me here is the pump breaker tripping on first use in the morning. When I reset the breaker, sometimes motor will buzz/hum then start, other times it will buzz/hum then trip the breaker again. Rapping the motor with a bat while it tries to start seems to help sometimes. After this, it will work the rest of the day without any problems. This doesn't happen every morning, just 2-3 days/week, more likely when cold weather. (no freezing, 35-40 is about as cold as it gets here) This problem is recent, it ran fine for years with same setup.

This is a 1hp A.O. Smith motor, on a Myers jet pump wired for 115V on a dedicated 20A circuit. Pump is rated at 18.6A/9A. All wiring has been inspected and capacitor tested good. Pressure switch new, set at 30/50. I realize wiring the pump for 230V would be preferable, but we have power outages occasionally and my generator won't do 230V.

Yime for a new motor? Can a capacitor fail intermittantly?