Old Briggs & Stratton
Look closely at the #'s stamped on the carbburetor side of this housing,under the silver & black sticker. These #'s are stamped in the metal , not part of sticker. Model # is first. Then a Type #. Then a Code# . The first two #'s of the code,is the year. Will look something like this. 80100 0168-01 59020207 Could be as old as 1959. If it has oil bath air filter, at least 50 years old. Mod-80100 Type-0168-01 Code-59020207 straight across like this.