The manufacture year of the engine will narrow it down to that year or the next model year. mtd products built in november or december are considered next model year. model number will either start with a 13 or 14 if you can't find any information from the mtd website PM me the year of the engine and info like deck size, drive type (gear (clutch or gas pedal type)) or hydro I am a yardman service center and can do partial model number searches by year.