Small Engines (Lawn Mowers, etc.): Toro B and S Lawn Mower Engine, six horse, manual states

Question
My five year old six horse Briggs (12J802)on my GTS-XL Toro self-propelled is running very rough.  The new plug is badly carboned and it is sucking gas.  I tried another plug and no change. The manual states that the carburator is not adjustable.  Any ideas?

Answer
The carb is not adjustable.  Have you checked/replaced the air filter?

If so,then your carb is porbably dirty.  You can drain the fuel tank and then remove the carb bowl nut located on the bottom of the carb to drain the carb.  Make sure the bowl nut holes are clean. You can, if you are very careful, remove the carb bowl and check for dirt.

Let me know what you find.
Eric