jet pump question

[mr. farmer]

I have a Goulds J5 twin pipe deep well jet pump. After the pump pressurizes my system to 60psi, the pressure slowly drops to about 30psi after about an hour. The pump turns on and repressurizes the system to 60psi and the cycle begins again. When I close the valve between the pump and my water tank, the pressure drops more quickly.

Is this a problem with my pump or is this typical behavior? Thanks.

[WV Hillbilly]

If no water is being run anywhere the pressure shouldn't drop . You have a leak somewhere . Which side of the valve you're closing is the pressure gague located on ? The pump side or the tank side ? I'm guessing the gague is on the pump side of the valve . When you close the valve you isolate the leak from the water & pressure in the tank . That would mean there would be less water & pressure on the pump side of the valve & it would leak off more quickly . It would be a fairly small leak to take an hour to lose 30 pounds pressure .

[nhmaster]

You have a suction line leak, probably the foot valve is bad. You will need to pull the well line.