Ensure the Briggs & Stratton engine is not running. Let the engine cool before attempting any troubleshooting.
Check the left side of the engine for the carburetor, which has a distinctive bowl shape. There is a circular choke part that is attached to the top of the carburetor with a linkage rod. Remove the bolt holding the linkage rod in place against the circular choke part by unscrewing it with an adjustable wrench. Use your hands to unhook and pull out the other side of the linkage rod. Set the rod aside.
Slide the replacement linkage rod in place. Secure it to the top of the circular choke part by reinserting the removed bolt with your adjustable wrench.
Spray a generous amount of WD-40 along the linkage rod to lubricate it.