fuel problem


Put new fuel filter in pump put it all back together ran fine for a while then it went down on an injector.Took them out cleaned out filters ran fine then did it again think im getting an air lock any ideas how to cure it im getting a bit fed up taking it to bits.
I have sorted it, it was an injector problem it kept getting stuck or something would run fine then it went down.Kept taking them out got fed up run the bike tapped the injector with a screwdriver and it started working.