Fill the crankcase with a 50/50 mix of 30 weight oil and Kerosene or Diesel fuel, fire the engine up, and idle it for about 15 minutes. Don't drive it or put any load on the engine, just run it at a slightly fast idle until it warms up, then drain it while it's warm. You'll be surprised at the crud that comes out!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!