Hawaii pool owner here, in ground, 16,000 gallon pool, beautiful deep blue tile installed about two years ago. Small pump, Sand filter with a little DE power added.
Trouble Free Pool has been my bible for pool care for the 2.5 years, when I found the site. I use the TFP app on my iPhone for all calculations and learned most of what I know from this site. My pool has been absolutely trouble free the entire time and I can let my kids swim in it knowing exactly what condition the water is in....thanks to this site. Anyway, on with the story:
So I hear some funny sounds out at the pool this morning and see the pump isn't creating that familiar flow on the surface of the pool. I go out and see the pump is running but has lost it's prime. Turn it off, check the leaf strainer and clean it out...nothing wrong there so I pop the basket on the pump open and clean it out...nothing wrong there. So I use the hose to preprime the pump and start it back up and it starts working fine then chugs some water and finally loses prime. I consult this forum for ideas, get a few and check the input to the impeller for clogs, nothing. Pop the sand filter open just to look in and all seems fine. So I decided to backwash a bit through to see what happens. Same thing, pump runs for a bit then chugs and quits. Checks the leaf basket and all seemed to be fine.
Finally after troubleshooting for a half hour, I decided while the pump is running dry to check the leaf basket and sure enough it was dry. Turns out some leaves had jammed the door enough to allow the basket to fill when the pump was off...making it look fine, but not allowing water to flow enough to keep the pump primed. It's a bit of a walk from the pump to the basket, so the half minute or so it was taking me to check it after turning off the pump was hiding the problem!
Just had to share.