How are you doing the two man? Pump 5 times, hold pressure, call DOWN, crack nipple (use clear tubing and glass bottle), fluid comes out, close nipple as flow slows to crawl, close nipple, call UP, repeat until no more bubbles coming downstream. watch for bubble going upstream. Monitor resevoir regularly. Start at back.
i don't like vacuum versions. YMMV.
I am still at a loss as to how teh air is getting in teh master to come up to resevoir. I would think if there was aproblem with teh grommets, you'd have a leak.