The primer bulb sucks gas through the carb.
The filter will go directly to the carb.
the suction side of the primer goes to the other carb port.
the other primer port goes to the gas tank (Return line no filter.)
If you are unsure of the carb in and out ports try it one way and see if you can suck gas thru. it. if not reverse the lines.
bob
March 2008