Small Engines (Lawn Mowers, etc.): lawn mower pulsing w/ gray smoke, gray smoke, correct oil

Question
Hi,

First of all, I want to say thanks for the help that all you guys offer!

Background info: The last time I cut the grass, I had to clean out the underside of the deck (caked up grass) and set the mower (Honda Harmony) on its side without shutting off the fuel valve. I now know not to do that!  When I started it back up I saw gray smoke spewing out of the exhaust, but it eventually went away and I finished cutting the grass.

Current problem: When I started the mower today, it was, again, spewing lots of gray smoke out of the exhaust.  But this time, the engine was also 'pulsing' and had a rough idle. It looked like the throttle for the carburator was unstable (moving back and forth).  I also noticed that there was oil in the air filter.  

I'm guessing that the smoke is due to the oil in the filter, but I wasn't sure since it was accompanied by the 'pulsing' and it didn't go away in a few minutes.  

Do you have any suggestions?

Thanks in advance for your help!
Jason

Answer
Hi Jason,

Most likely there is no serious damage.  I would clean or replace the air filter.  The oil in it would cause smoke and restrict the air flow causing rough operation.  Check the crankcase for the correct oil level.  Lastly, check the spark plug and try a new one if needed.

Let me know how you make out.
Michael