One end goes to the carb and the other to the gas tank. I have the original manual to my 3200, and unfortunately McCulloch did not provide an exploded parts view or even a complete parts list. Pretty poor huh? Take the air cleaner cover off(right on top....2 screws). Take the 2 screws out holding the handle to the body. Lay the saw on its right side (oil cap facing up) and remove all the torx screws on this side. This side of the saw cover will come off. Careful not to pull on it hard as there are the fuel line to the primer bulb, the electrical wires to the shutoff switch, and the throttle handle/spring that can come off easily. You should be able to put the primer gas tubing back in. If you've done this, you may want to replace all the carb tubing as it can become hard and brittle. Hope that helps.
Russ
October 2008