If your Briggs & Stratton engine on your small machine, such as a tiller, mower or generator, won't start or dies right after you start it, then you must diagnose the cause. If the spark plug is good and air filter is clean, then the carburettor most likely is dirty and needs cleaning. Over time the gas and debris can gum up and clog the carburettor and prevent it from injecting fuel into the piston chamber.
Locate the black rubber gas hose clamped under the gas tank on the Briggs & Stratton engine. Follow the hose to the end clamped onto the carburettor.
Unscrew the clamp holding the rubber gas hose to the carburettor with the flathead screwdriver. Slide the clamp down the hose.
Pull the hose off with your hand and point it into the gas can to catch the gas.
Point the carb cleaner spray can into the nozzle on the side of carburettor where the gas hose was connected. Spray cleaner into the carburettor for 5 to 10 seconds. Allow it to soak for 10 minutes. Point the pressurised canned air into the nozzle and spray it for 10 seconds.
Push the hose back onto the nozzle on the side of the carburettor. Tighten the clamp back onto the end of the rubber hose with the flathead screwdriver.
Unscrew the bolt from the base of the carburettor with the flathead screwdriver. The bolt holds the fuel bowl to the base of the carburettor.
Dump out the old gas in the fuel bowl. Spray carb cleaner into the fuel bowl and onto the area above the fuel bowl. Spray the pressurised canned air onto the area above the fuel bowl to blow away any debris on the fuel float and valves above it.
Tighten the fuel bowl back onto the bottom of the carburettor.