Pump not holding prime.

First a little background: I have been getting some fine sand in my tub, sinks & toilet. Quite a bit in fact. I have been gone for a few weeks. While gone the pump lost pme. I went out there & poured water in the inlet on top of pump where I have a ball valve. The pump primes, but takes some time. I had to fill it up several times, & every time I open the valve to the water softner I have to open it real slow. It still loses prime most of the time. Sometimes it will take, but then as soon as I open the valve to the house it loses its pressure & prime. When it first tries to prime before I open any valves the pressure switch cuts off & on real fast. I notice air bubbling up through the inlet valve on top of the pump. It seems I almost get it every time, but then it will lose prime if I make it through the first valve opening to the valve that goes to the house. That pressure switch cuts off & on real fast when I first turn on the power to the pump. I then have been attempting to open that first valve real slow. Seems the only way it will take. Some of the time. If it does I then have been moving to open up the other valve to the house & that is when it usually loses its prime. I did raise my drop pipe about 3/4 of an inch to see if that would help with the sand problem.
Question: Do you think I need a new pump or is it possible its just the check valve messed up from all that sand? Any ideas on the proper sequence to go about the process of elimination to find the problem? Thanks in advance. Turkeyshooter.
Forgot to mention it is a Water Ace Jet pump. I also have a shallow well a few feet away with plenty of water that has a hand pump on it. That is where I have been getting my water from to attempt to prime the pump.

A jet pump uses pressure to make more pressure. The bladder tank needs to have enough reserve so that when you draw water, there is still pressure available to the pump.

It sounds like one, two, or three problems. The precharge on the tank may be too high, not leaving enough reserve or the bladder may be busted. The ejector on the pump may be plugged. The line to the pressure switch or the diaphragm on it may have sand in it causing it to malfunction. The same sand can cause the pressure gauge to read wrong.

Well someone told me they thought it was the foot valve. I pulled the drop pipe out & replaced the foot valve. All the water that was in the pipe was muddy looking. The old foot valve did not look that bad just had a rusty film on it. I put everything back together & same problem. A fellow at ace told me he thought it might be the bladder also, but after listening he changed his mind on that. I had air & no water coming out of the air valve on the bladder tank. I set it to 2 pounds below the cut in pressure as recommended by him. Attempted to prime the pump, but same reaction. Almost thought I had it one time, as it pumped for a minute after catching prime, then lost it. When its building pressure it hangs up for quite awhile around 20 PSI. Then it tries to prime, but if I don't close all valves it won't take. Then when & if it does it cuts on & off at the pressure switch real quick until I try to open up the first valve real slow. If I just open the valve all the way it loses its prime. I took the injector off & checked it & cleaned it up & put it back in. That area looks fine. So I will check that line to the pressure switch in the morning. IF that does not work, the fellow at ace said it may be I need to go down deeper with the well, until I hit rock. Which is around 175' for my area. Right now I am only approx 60', but I tied a heavy washer to a string line & dropped it in the well & it seems to bottom out around the 20 foot mark. It does hit water for around the last 8' but seems to be real muddy. Do you think I could pump it off with a hand pump since they have better suction I am told, & do you think its possible I had a cave in & just need to pump it off or what is your recommendation? Keep in mind that I have water on a shallow well at approx 15' with the hand pump only 10' away from the one with the 1/2 horse water ace.Thanks , Turkeyshooter

turkeyshooter said:

I had air & no water coming out of the air valve on the bladder tank...

Click to expand...

That is not conclusive. On many bladder tanks the air valve is at or near the top so the bladder can still be busted and some air trapped above the water. Water would only come out if it is 100% waterlogged. When checking and setting the air pressure it is important to calibrate the air and water pressure gauges. It's not unusual for the water pressure gauge to be way out of whack.

I don't understand how you have the valves setup. Is there a valve in between the pump and the tank? If so, closing that could cause the pressure switch to cut on and off. The pressure has to have somewhere to go and that somewhere is into the tank. Keep the valve on the exit side of the tank closed so that the pressure in the tank is available to the pump.