OH !! another pressure washer ! seems like you did all the right preliminary steps, are you holding the trigger "OPEN" on the gun ( with the water turned on) when trying to start it ?? if not.. try that, if no success that way, problem may be with the pump, it looks like a "flange-mount" ( 4 bolts / nuts ) try removing the pump from the engine and see what happens, be sure to take pics of everything you work on they become your re-assembly manual ... post back your results.