Lawn & Garden Equipment Engine Fuel Spitback Cup Shaft Seal. This fuel spitback cup shaft seal (part number 231032-S) is for lawn and garden equipment engines.Fuel spitback cup shaft seal 231032-S prevents fuel from leaking between the fuel spitback cup shaft and the air cleaner cover.Wait until the engine is ... - Lawn & Garden Equipment Engine Fuel Spitback Cup Shaft Seal.