4/1/15 Used in Bolens lawn tractor model series 760-770. I found and downloaded manuals on the tractor mower (3), but did not have any B&S engine info. in those manuals. Mainly, looking for basic maintenance info., e.g., oil change scheduling, oil capacity, type of oil, filters, etc. The info. I took off the engine follows: Briggs & Stratton Engine, Power Built, model 31, 13.5 hp, 344 cc. Thanks F. Lostutter fcl56sdl@yahoo.com