a few drops of mmo should not hurt a thing it will lube the intake valves guide don't get carried away with the stuff and you should be good to go. when you go to store it again pour in some fuel stabilizer and run the engine drain out the fuel tank and run the engine until it quits with the empty tank. Drain the crankcase oil while its hot and put in your favorite brand and type of oil in the case then crank the engine over to splash the oil around then kick back and enjoy your favorite beverage. If you can find a storage oil use that to pickle the engine and a descant plug to put in place of the spark plug but now I'm getting carried away. I'm guilty of parking the lawn mower with no regards for it for winter or long time storage as i know I can always make it start again I treat it like a red headed step child I'll bet the grass cheers when I put the mower in the shed for winter.

Norman