Okay, here's a quick update.....I pulled the fill valve, tore it down, and there was a piece of lime scale blocking over 1/3 of the sceen. I thoroughly cleaned it, put everything back together, replaced all the missing screws, yada, yada, yada.....worked great for one cycle!!!! So, my guess is that the shut off valve hasn't been used in quite a while and after exercizing it, some scale broke loose and plugged the screen again. So, I'll tear it down again and see what I've got. I may exercize the valve a bit and run the thing through a couple cycles to try and get all the scale through the line.

Any thoughts, ideas?