How to Repair a Lawn-Boy String Trimmer

Switch the Lawn-Boy's ignition button to the "Off" position. Wait for the head to come to a stop, and lay the trimmer on the ground to cool off for 10 minutes. Brush off any debris along the outer engine and the shaft, and on the head. Wipe off any oil, dirt or debris with the rag.

Pluck off the rubber boot attached to the tip of the spark plug. Set the spark plug socket into the socket wrench and loosen the plug, pulling it out of the cylinder. Fit a new plug into the cylinder and tighten it down with your fingers first, then with the socket wrench.

Remove the cap on the fuel tank and pour all the remaining fuel into a fuel container. Lift out the fuel filter and fuel hose, using the metal hook. Pry off the filter from the hose. Check the condition of the hose. Service the fuel system if the fuel hoses look brittle or are cracked.

Attach the fuel filter to the end of the fuel hose, pressing the filter's nozzle into the hose. Press both of them back into the bottom of the tank. Unscrew the air filter cover. Pull out the filter and brush off the cover, filter and area around the filter. Wipe away any dirt or dust from these areas.

Check over the entire area for any loose screws, broken or missing parts. Make any further repairs to the trimmer as necessary. Take the trimmer to a professional to handle other technical repairs as required.