Perhaps the problem is the N, or M needs to be done in 1" instead of the 1/2 or 3/4" pvc. Since it's filling with 3/4" lines. This would allow it to drain a lot faster, and there wouldn't be enough water coming in fast enough to keep the siphon flowing, thereby allowing it to release and the barrel to refill.

To make this adjustment though I have to do 2 things. 1) Spend more money on a wing and prayer chance. 2) Ruin one of the threaded bung hold plugs that I have drilled the center out for the 3/4" pipe. You can always go bigger, but not smaller. So IF I drill it out, and it doesn't work. I am screwed.

Does anyone have any advice? Anyone? Please explain to me why this isn't working.