The normal way for a purge bulb to work is the fuel hose from the tank (one with the fuel filter on the end) goes to the carb elbow nearest to the pump side of the carb(plate usually held with a single screw) the pipe from the metering side of the carb goes to the suction side of the purge bulb, the pressure side of the purge bulb takes the fuel back to the tank, so to re cap the bulb pulls fuel from the carb and back into the tank, not the other way round.
Husqvarna man, December 2009
