Yes, the entire Berryman B-12 Chemtool family of gasoline fuel additives, including Fuel System Cleaner (part #0116) and Total Fuel System Clean-Up (part #2616), are completely safe for use in small engines. 0116 contains a blend of 100% strong solvents to dissolve gum, varnish, and fuel residue, while 2616 contains those same solvents along with our strongest detergent package for an even deeper clean. 2616 also contains fuel stabilizers, which are critical for the year-round protection of such equipment.