Well I opened up the trigger group, polished and lubed all contact surfaces then adjusted things after reassembly. The pull is now very light and much smoother with a short second stage.
if you are filling a tank it's going to take a long time.......you won't get any air coming out on the up stroke as that just does the second stage in the pump, output only on the down stroke...check the pump with the plug and see if it does develop the pressure it should, adding a drop or two of silicone oil at the intake doesn't hurt either...a 500 cc. tank take forever to fill with a pump....