suck on the opposing end while the machine is off? all kidding aside... new pump could be faulty. try to verify that the pump works at all. i would complain to the person who sold you the pump and see what they can do for you. you may have ruined the seals that make it work by not priming it properly before the first run. use the gravity siphon prime method. put the pickup tank above the output and gravity prime it. (i'm imagining a pump with a pickup hose.)