Small Engines (Lawn Mowers, etc.): Very gassy lawn mower, air mixture, gas bomb

Question
I have a lawn mower with 10 hp kohler engine.
Serial 5139566
Mod K241S
Spec 46664d
After mowing for half hour or even less one smells like a gas bomb. This is a long standing problem. We have lived with it for years-seems to be getting worse. Power is okay-sort of. I tried mowing without the airfilter-no change. Could this be a carb setting.
Thanks very much for your help.  

Answer
Hello Reg:

From your Description it Sounds like the Carburetor is Set too Rich.  The Following it the Instruction File for Setting the Air Mixture Screws. The Procedure is the Same for 1 or 2 Mixture Screws, Just Use the Instruction File and Skip Over the Section with the Missing Mixture Screw. Now Setting the Air Mixture Screws:  ****Turn the Idle Air and Main Air Mixture Screws In Until SNUG **Do Not Jam** Then Reverse Both Screws 1 1/2 Turns. Holding the Throttle Full Open, Start the Engine. Turn the Main Air Mixture Screw Clockwise Until Proper Revs are Obtained. Occasionally you May have to Turn this Counter Clockwise to Achieve the Proper Revs. Now Allow the Engine to Idle. Set the Engine Idle Screw (Not Idle Air) so the Engine will Stay Running if Required. Now Set the Idle Air Mixture Screw so there is No Hesitation when Throttling from Idle to Full Throttle. Reset the Engine Idle if Required.**** You can View a Breakdown of the Engine at this Site Addy; http://www.kohlerplus.com/login.asp and Select Enter as Guest. Now Select the Thumbnail of the Engine Catalog you Wish to View. If you Hit a Snag or this Does Not Correct the Problem,  I am Here if You Require More Assistance. Hope this Helps. Let me Know What Happens, Please. May the All Mighty Bless You and Yours. Thanks.

Good Luck

Respectfully

John

PS: I am Allowed to Answer 10 Questions a Day. If you See I am Maxxed Out, then Try Submitting your Question at or Just After 8pm EST (US). My New Day Starts then. Thanks.

Respectfully

John