singlewhip
New Member
- Messages
- 2
- Reaction score
- 0
- Points
- 0
I have a sears 3/4 hp shallow well pump 390.2578 that I bought used on ****. I replaced an old pump with this pump. Sometimes I will use this pump on a shallow well and sometimes (currently) I use it to pump water from a spring holding tank (low positive inlet pressure)to my house. I need about 60 psi out of the pump to make everything work right. When I first got the pump it would easily go to 70 psi. I set the pressure switch to 40-60 and everything worked fine. I make a mistake and had sked 40 pvc on the out let side and vibration eventually broke the connection. I lost about 1,500 gallons of water and the pump ran dry for a while. I hooked everthing back up with steel pipe carefully and have no leaks. The pump will now only go up to 48-49 psi. I broke down the pump and everything looks ok. Hard to tell if clearences are off.
I have ordered new impeller and defuser and "O" rings.
In order to use the pump until new parts come I need to change pressure setting so that the pump comes on at 40 psi and off at 48 psi. I can't go much below 40 psi or the system that is in place won't work because of lost of pressure going up hill. I don't seem to be able bring the on/ off pressures closer that about 20 psi. I have backed off the small nut in the pressure switch all the way and am still left with about 32/48 psi.
I would appreciate any advice.
Thanks, singlewhip
I have ordered new impeller and defuser and "O" rings.
In order to use the pump until new parts come I need to change pressure setting so that the pump comes on at 40 psi and off at 48 psi. I can't go much below 40 psi or the system that is in place won't work because of lost of pressure going up hill. I don't seem to be able bring the on/ off pressures closer that about 20 psi. I have backed off the small nut in the pressure switch all the way and am still left with about 32/48 psi.
I would appreciate any advice.
Thanks, singlewhip