If you are having a problem with your Briggs and Stratton lawn mower, whether it be reduced engine power or an inability to get the mower started, it may be due to a number of issues including improper oil levels, old or tainted fuel or faulty spark plugs. If you have a basic knowledge of small engines, you will easily be able to complete most of the repairs needed to keep your Briggs & Stratton mower engine in working order. If you are less familiar with basic engine information you may wish to refer to the owner’s manual for your specific model as a guide.
Check the oil level in your Briggs & Stratton engine with a dipstick. Low oil levels can contribute to the engine overheating and stalling during use. Keep the oil tank filled to the line marked “Do Not Overfill” on your dipstick.
Check the air filter in your Briggs & Stratton engine. Remove the filter if there is excessive dirt buildup; excess buildup can affect the operational power of the engine. Check your Briggs & Stratton owner’s manual to find out what air filter type your mower engine uses. For paper filters, unscrew the filter cover and remove the paper filter underneath. For foam filters, unscrew the filter assembly secured to the side of the engine and remove the entire assembly. For dual element filters, loosen the filter assembly cover knobs to remove the cover. Underneath, you can hand remove both the foam pre-cleaner and paper filter underneath.
Replace the air filter unit in your Briggs & Stratton mower and secure the filter cover. Foam filters should be soaked in clean engine oil just before installation. Soak your foam filter in engine oil a few times during each lawn-mowing season.
Check the vented fuel tank cap and make sure that vents are not clogged. Use your screwdriver to knock off any dirt buildup from the vented fuel tank cap.
Remove the fuel tank from your Briggs & Stratton mower. Use a fuel line clamp to seal the fuel line leading to the carburetor. Disconnect the fuel line from the tank. Empty the fuel if it has been there for longer than 30 days or if it has become diluted with water. Both of these conditions can render the gasoline incombustible.
Check the inlet screen on your Briggs & Stratton engine. The inlet screen will be revealed when you remove the fuel tank. Remove the inlet screen from the mower and check it for dirt buildup. Use compressed air to blow away any buildup from the inlet screen holes. Do not perform this step near the engine, as compressed air may damage some critical parts inside the engine.
Secure the fuel tank back into place and remove the fuel line clamp.
Remove the spark plug from the spark plug lead on your Briggs & Stratton mower. Reference the owner’s manual for model-specific plug lead locations. Test it with a spark plug tester and replace if necessary.