Hello! I have a Hayward 36 sq ft DE filter (don't know model, sticker came off a long time ago) with a 4 port Hayward selecta-flo valve. I just had 3 of the grids replaced, got everything back together, and can't get the pump to prime. This happens every time and every time I mess with it until I'm ready to go play in traffic and then it suddenly starts working. Problem is I never remember what I did. The motor is new, there are no leaks, all o rings are in good condition and lubed, I clean out and fill the strainer basket, open the air release valve, and NOTHING. I can initially hear air escape but no water ever comes out. The psi stays at 0. I checked for blockage in the strainer and the skimmer. I don't know what setting the valve should be on (I've had it on "filter") or what direction the jandy valve should be in. Please help!!!!!!!!!!!!!!!!!!!