My lake pickup line never fills with water

[Mario Russo]

I am having trouble keeping my pump primed with a 60ft flexible 2" line that lays in the lake to feed my irrigation system. I thought I had a leak from the pump to the foot valve in the lake so I finally disconnected the 60 ft flexible line and layed it on my dock. I filled it up with my hose and 10 min later the water is dropping.
I add more water and ten minutes later it drops again meanwhile there are no leaks. I hook it back up to my pump fill the line with water ( I have a tee at my pump ) irrigation system works great. I come back 24 hrs later my line is down about 2ft loosing my prime to the motor. Keep in mind I took the line out of the water to check for leaks and none. I thought the check valve was defective but no. I have about a 25% grade down to the pump and lake. Why is my pickup line in the lake loosing water. Also after my irrigation is working should that not take care of any potential air pockets in the 60 ft pickup line and the foot valve hold the water? What the hell is going on?

 

[WorthFlorida]

The foot valve is leaking. There is probably debris in the foot valve preventing it from fully closing. Another is the spring tension is gone or the spring in the foot valve broke and it can't close the valve. These springs are generally stainless steel so they last a long time. After it is primes and the pump is working, shut the pump off and put your ear to the pipe leading to the lake. You'll hear the water trickling back. It could be possible that there is a pin hole somewhere.

I had a $180 3" brass spring loaded check valve that was in a horizontal position, at about a year old would not close and I would lose prime all the time. I took it apart and it all looked good, reinstall and it still would not fully close. The fix was a cheaper PVC check valve.

Your foot valve maybe PVC. This one is all brass and SS.

 

[Sponsor]

 

[Taylorjm]

Our pump just has a large spring check valve between the intake hose and the filter that sits on the bottom of the lake. Never had an issue with losing prime.

 

[HappyLaker]

Just a thought.... with your line on the dock not much gravity pressure to show a foot valve problem. When you put that line back on shore if there's a grade that would mean more downward pressure on the foot valve because of gravity and maybe the seal in the foot valve is reacting differently thus losing water? My best guess replace foot valve and see what happens