The fuel system on a Poulan chainsaw, as in most small engines, includes a small diameter clear plastic tube. Attached to one end of the tube is a fuel filter that resides inside the gas tank. The other end of the tube connects directly to a small diameter metal tube on the carburetor. Replacement fuel lines are relatively inexpensive, 3 to 5 dollars, and are easy to replace. In addition to replacing the fuel line it may be a good idea to replace the fuel filter as well.
Empty the fuel tank on the chainsaw of any remaining fuel. Pull the cap from the tank and turn the unit upside down. Drain the fuel into an approved fuel container. If the fuel is old (more than about a year) dispose of it according to local regulations for hazardous materials. (Fuel can be kept longer by adding a stabilizer.)
Pull the fuel line where it attaches to the carburetor using the end of the needle-nose pliers. The old fuel line may take some force to pull free from the metal tube.
Push on the fuel line to feed it into the fuel tank. Hold the chain saw upside down. Shake the unit to get the fuel filter into the opening of the tank. Pull the filter free of the tank. Feed the remaining fuel line through the access hole at the bottom of the tank. Dispose of the filter and old fuel line in accordance with disposal regulations.
Feed one end of the new fuel line into and through the bottom access hole of the fuel tank. Push approximately 6 to 8 inches into the tank. You can pull back any excess line later. Grab the end of the plastic line with the needle-nose pliers. Bring the line through the gas tank fill opening.
Attach the new filter to the end of the new fuel line. Feed the filter back into the fuel tank. Pull any excess line from the tank. You will want approximately 3 to 4 inches of fuel line inside the tank.
Route the new fuel line to the carburetor. Cut the line to length with the cutters on the needle-nose pliers. Attach the line to the metal tube.
Fill the fuel tank with fresh gas-oil fuel for 2-stroke engines and start the chainsaw. It may take a few pulls to prime the new line with fuel.