Small Engines (Lawn Mowers, etc.): Dirt in the Carb, kerosene oil, garden tiller

Question
I have a lawn vac with a 8.5 Inntek B&S motor.  Still very new.  Less than 30 hours on the engine.  I use it in sometimes very dusty conditions.  I pulled the aircleaner yesterday after is was running rough to dicover that the fliter and prefilter were VERY dirty and it had sucked dirt past the filter gasket.  I wiped the dirt all out of the carb and exposed areas, flushed the carb as it ran with WD-40, then changed the oil.  Running OK, however would it help if I run some diluted (kerosene) oil for a few minutes to flush the dirt from the rings and crank?  Don't want to have this die because of my foolish mistake.

Answer
Kerosene will flush the engine.  The most important thing you need to do is change the oil several times after flushing.  You are trying to remove the silicate material from dust that enters the engine.

Oil for a small engine is relatively cheap.  I change my oil in my mower at least twice per season, and our season is short.  A quart of oil is less than $3.00 and will provide about 2 oil changes.

In the case of the vac or a garden tiller, I would change the oil every time I used it becasue the enviornment they run in is extremely dusty.  They sell oil change pumps on many websites for about $50.00.  This makes changing the oil really simple...less than 5 minutes.   

http://www.tooldiscounter.com/ItemDisplay.cfm?lookup=MIT7400&source=froogle&kw=M...

Just use you vac, when you are done and the engine is still warm, suck out all the old oil and refill.  Simple and will extent the life of the engine.
Eric