I have a shallow well pump(1/2hp)... it has worked for the past 2 years just fine, this year when I hooked it up it will build up pressure (and make the switch cut off @ 50lbs.) but, as soon as I turn on my sprinkler it will drop to about 10 lbs of pressure in 15 seconds or so and then drop to zero lbs. Of pressure and nothing but a trickle will come out... shut off the sprinkler via the hose bib attachment and the pressure builds right back up to 50lbs. And the pump cuts off-it is an above ground pump w/an above ground check valve... when I prime the pump it seems as if there are a lot of tiny air bubbles that continuously come out... I have primed it 12-15 times,replaced the check valve and resealed all connections... before I lay out more cash for a new pump... I wonder if my well has dried up! Can some please offer some advice before I go either crazy or broke! Thank you!

1. Does this system have a pressure tank? If so, then sounds like the tank might be waterlogged. Press the little air valve at the top for several seconds. If water comes out, then its shot.
2. If you don't have a pressure tank, then I would consider just putting an on/off switch on the pump as opposed to a pressure switch.
3. Assuming this is a shallow well pump with one line going into the well, I'm wondering why you are having to prime the pump so often. With that type of well, I'm thinking you will still want to replace the footvalve even if you have a CV above ground. You will still have empty pipe below the CV if the footvalve is leaking.

Thank you for a speedy response, I do have a pressure tank(bladder style about the size of a watermelon)it has about 28 lbs. of air and is holding pressure. And I do have an on/off switch(sorry I wasn't clear what kind of switch I had)... In addition, you assumed correctly... It is a shallow well pump with 1 line going into well-the reason I primed it so often is because the local well pump guy said "it's probably the prime on the pump...make sure it's primed correctly cause it's gonna cost money if I come to your house"... and replacement of the footvalve doesn't seem to be an option do to the fact that some one had poured a concrete pad over the well to mount a stand for the pump!?

Hard to give you much advice sitting 500 miles (or whatever) away from your well. It seems that your pump is just not supplying an awful lot of water.You might try pulling off the impeller cage and checking for trash or broken impeller vanes inside.

You are using this for irrigation, so the pressure tank might be strictly an option. I'd be really tempted to just hook the pump up directly to the sprinkler system and forget the tank. I think you are noticing such a rapid initial loss of water because the tank is small and the sprinkler pipes are initially empty. But you would think it would refill fairly quickly, even with the sprinklers on, if the pump could supply plenty of water.