Things You'll Need
Spark plug wrench
WeedEater gas lawn mowers use Briggs & Stratton engines, like many other makes. They are generally dependable, but, like any gasoline engine, may develop problems at times. Mowers also can develop problems not directly related to engines, such as loss of power, vibrations, and uneven or poor cutting. You can troubleshoot and solve most of these problems without calling in a repair tech. Refer to your owner's manual for specific details about your particular lawn mower.
Start with the basics if the mower won't start. Make sure the spark plug is firmly connected. Remove the plug with a plug wrench to see if it is burned or fouled and replace it if necessary. Check the fuel supply and be sure the engine has fresh fuel. Keep the control bar on the handle firmly depressed. Examine the air filter by removing the top of its container with a screwdriver; clean or replace it if it is dirty.
Repeat the same checks if your mower starts but quickly dies or runs rough. Also check the fuel cap to see if an air vent is plugged, and examine the muffler to make sure it is not clogged. Remove the air filter and clean the carburetor. Spray automotive carburetor cleaner into the carburetor and on the throttle and choke control levers to clean any debris from them.
Check the wheels if the mower is cutting unevenly or is dragging. Adjust the wheels so that all are the same height. Raise all the wheels if the mower is cutting too low or is cutting so much grass it is building up under the mower deck and interfering with the blade. Also check the wheel adjustment if the mower is hard to push.
Check the blade if the mower is not cutting grass cleanly or is tearing it. Sharpen the blade or have it professionally sharpened if it is obviously dull or has nicks or broken spots. Also examine the blade if the mower is vibrating excessively; the blade made be bent or out of balance. Replace a bent blade and have an unbalanced one professionally sharpened.