Riding lawn mowers, along with all gasoline engines, require a fuel line that is free of cracks or any defects. Over time, these rubber-based hoses will succumb to weather elements and chemicals in the gasoline. When this occurs, the fuel line will need replacing. While the fuel line is being replaced, it's good to replace the inline fuel filter as well. Replacing these items will not take long to perform if you have the correct fuel hose, the proper filter and a couple of hand tools.
Remove the spark-plug wire from the spark plug. This is a good safety practice whenever servicing any type of gasoline engine. Pulling the thick, rubber wire from the spark plug will disable the engine from starting while performing service work.
Locate the rubber fuel line on the lawn mower. Typically, the fuel line will run from beneath the gas tank and into the carburetor.
Remove the filling cap from the gasoline container. Set it next to the lawn mower, near the carburetor.
Use the needle-nose pliers to grab the spring retaining clamp that secures the rubber fuel line to the carburetor. Squeeze the two metal jaws together to loosen the spring clamp.
Pull the clamp rearward onto the fuel line. Grasp the hose with your finger, and pull. It might take some effort to remove the hose from the small fitting. Place the end of the hose inside the gasoline container.
Allow the gas tank on the mower to empty its contents into the gasoline container.
Remove the fuel line from the bottom of the fuel tank in the same method as you performed with the carburetor in Step 5.
Lay the old fuel line next to the replacement hose. Trim the new fuel line to length with the knife.
Locate the position of the old fuel filter on the old fuel line. Cut the new fuel line in half at the fuel-filter location.
Insert the new fuel filter into the new fuel line, using the old spring clamps from the fuel line you removed. Some fuel filters might have extra spring clamps packaged with the fuel filter. Use the new clamps if they fit the replacement fuel line.
Install the new fuel line on to the bottom of the gas tank first. Route the new fuel line to the carburetor in the same path as the old one when you removed it. Insert the fuel line onto the carburetor fitting.
Add fresh gasoline to the mower until the gas tank is one-third full. Check for any fuel-line leaks. Reconnect the spark-plug wire to the spark plug. Start the lawn mower. Check for leaks.