Since the saltwater conversion everything has been automatic and on cruise control. No problems of any kind. Back in the Spring I noticed the pump was having a little trouble priming, so I changed the O-rings on the shaft in 3-way diverter valve, cover gasket on diverter valve, o-rings for drains on pump and suction strainer, the cover o-ring for the suction strainer, and the o-ring at the union connection to the suction strainer. No more priming problems. Around the same time or a little before, I had some "hard-start" problems with the pump (motor). It would buzz and be slow to start, and sometimes it didn't start (this was before it was on a timer, so I was standing right there to observe). I seem to recall that one time when I tried to start it, I saw the cover raise up on the skimmer basket, as if water pressure(?) pushed the basket up. I assume it had attempted to run backwards at that moment.
So I changed the start capacitor in this 230v-1ph motor, and it was good as new. No problems of any kind.
Fast forward to this morning. As I said, I don't always pay that much attention to it, so it could have been the same way yesterday, but as I glanced out today I noticed there was no movement in the water. So upon inspection I find the pump is running, but not primed. As usual, the water is crystal clear, and not even a leaf in the pool anywhere. I removed the cover from the suction strainer and notice the water is hot (warm), so I know it's been churning since the pump kicked on 30 minutes previously.
NOTE: (could be important?) I did notice that one of the skimmers had the cover lifted, and the basket was not in position. Could the pump be running backwards? (I doubt it). I didn't have much time, but thought maybe the sand filter is clogged, but that didn't make much sense either. Briefly tried the valve on waste, but it didn't prime - maybe needed more time and I'll try again.
So, has anyone experienced this? Where there does not appear to be anything wrong and the pump simply won't prime...although working perfectly up to that point?
Thanks for all the help!