Outdoor Power Equipment (Lawn Mowers, Snow Blowers, Chain Saws and more) Discussions

I have a Kawi OHV powered walk behind 21" mower. I use the mower exclusively in the mulching mode and therefore  like to clean the underside of the deck every two or three weeks. I put a floor mat on the ground and  flip the mower up on it's nose with the handles leaning on a saw horse. My issue is the smoking of the engine through the exhaust the next time I start it up. Obviously oil is getting into the combustion chamber due to the head down position the mower is in when I clean the deck. The plug does not foul and the smoke clears after a few minutes. Am I doing any damage?

Marc