Shurlfo Extreme 5.7 Water Pump Not Holding Prime

[Lindsay]

Hello,

My water system is driving me nuts. I turn the pump on open a faucet and it takes about 3 to 5 seconds to get primed and have pressure. Now that it has pressure I can shut the faucet off and the pump stops. Let it sit for a minute or two. Turn the faucet back on and it has lost prime and now it seems to take alot longer to prime back up. If I turn the faucet off at this point The pump just keeps running and never does get primed. All plumbing connections seem to be tight. Water Pump in question is Shurflo Extreme Smart Sensor 5.7 Water Pump

Any help on this would be greatly appreciated,

Thomas Lindsay