Two days ago, my pump was working fine with any of the 3 inputs selected: spa, vacuum cleaner or skimmer. Yesterday, I couldn't get the thing to prime from any of these sources. All I'm getting is a trickle of water into the pump basket. I'm getting suction at the pump basket, because the low pressure fogs the clear cover almost immediately; when I "unlock" this cover I can feel resistance - then there's a release and the water drains back into the filter basket.
The O-ring in the pump basket lid is in excellent condition. Basket is clean, fliter and cannister are clean, pump input line is tight with dope on the threads.
Between the pressure outlet side of the pump and the filter canister, I have a J-valve. One output is to the filter canister, and the other is a drain line to the street to lower the water level in the pool. With this valve cracked on the drain side, I should be allowing any air to escape from within the pump.
Today, I tried filling the pipe from the Skimmer to the pump. It shares a J-valve with the vac, so I screwed a threaded plug into the pool vac intake so the water wouldn't leak out from that pipe. Next I removed the J-valve cover and filled the pipes to the skimmer and vac with the garden hose. This also filled the pump basket. I replaced the J-valve cover and the pump basket cover.
The water sucked the pipe dry quite nicely, and then only produced a trickle into the basket.
Any ideas are GREATLY appreciated!