Briggs & Stratton is the manufacturer of a variety of small engines used in lawn and garden equipment such as lawn mowers, pressure washers, roto-tillers, log splitters and more. These engines are typically single-cylinder, predominantly four-stroke models, and come with either a vertical or horizontal crankshaft. These Briggs & Stratton engines employ a governor to help keep the engine running smoothly under all types of workloads. If the engine is running roughly under heavy workloads, you may want to troubleshoot the Briggs & Stratton governor to make the engine run smoother.
Pull on the black rubber boot at the tip of the spark plug to disconnect the spark plug wire from the spark plug.
Locate the governor arm on the side of the engine. Inspect the linkage and spring between the governor arm and the throttle on the carburetor. If the linkage and/or spring are damaged, replace with genuine Briggs & Stratton parts.
Rotate the governor arm to the left and the right. The arm should move relatively freely, and should in turn open and close the throttle on the carburetor.
Loosen the nut at the base of the governor arm one to two turns by turning the nut counter-clockwise with an open-end wrench.
Push the throttle control lever all the way forward, opening the throttle on the carburetor to the wide-open position. As you move the throttle control lever, watch the governor arm to see in which direction it moves as you open the throttle.
Push the governor arm in this same direction manually as far as it will comfortably move. Hold the arm in place with one hand, and tighten the nut at the base of the governor arm with a wrench in the other hand.
Release the throttle control. Rotate the governor arm left and right once again, to make sure that the arm continues to move the throttle on the carburetor, as in Step 3.
Reconnect the spark plug wire to the spark plug, and start the engine. Allow the engine to warm up for a few minutes, before putting the engine under varying levels of work. The engine should run smoothly under almost any condition if the governor is adjusted properly.