Before I got a new pump, I struggled with this very problem. I would go ahead and hook my vac head to the hose and the pole and then hold the other end of the hose against the return jet. Not momentarily, mind you, but for several minutes. I could watch all the big air bubbles come out of the submerged vac head and then smaller bubbles, and then when I could see no more bubbles coming out, I would very quickly put the plate into the skimmer. Sometimes I would not do it quickly enough and lose the prime and then have to start over. It was a huge pain in the butt! I can't offer any other suggestion other than to tell you how I did it, but I know how frustrating it is!