Cavitation at end of pump cycle

[Cobra1365]

I am experiencing some cavitation at the end of the pump cycle. It’s not the pressure switch chattering, I can hear it in the pump itself.

I have a shallow well (28yrs old) with a 1/2hp Gould jetpump. Pressure switch is 30/50 and tank is set to 28. Tank is good, pump is a yr old. Pump comes on at 30 and shuts off at 50. Plenty of water pressure at all times. But, I get three to four clunks in the pump right as it approaches 50.

So,
Bad footer valve? Wouldn’t that cause loss of prime?
Well finally going? Our water table here is pretty close to well depth.
Attic vent not moving enough air?

 

[Valveman]

Most likely you have s suction leak. The leak causes cavitation just before the pump shuts off, because that is the point it is pumping the least amount of water, and the little bit of air tries to take over. You could also just be shutting the pump off too close to the max pressure that pump can build. The pump maybe worn down a bit and not building as much pressure as it used to. Fix the suction leak or turn the pressure switch down, depending on which of these problems is causing the issue.

 

[Sponsor]

 

[Cobra1365]

Thanks. I’ll do a leak check and or turn the pump down a tad.

Wouldn’t a suction leak also cause loss of prime?

 

[Valveman]

Not always. Just a partial loss which is cavitation.