Small Engines (Lawn Mowers, etc.): Lawnboy loses power, carb settings, factory specs

Question
I have a 6.5 Dura Force Lawn Boy. While mowing it began to lose power. I replaced the plug and it gained enough power to finish mowing however began to lose power again. I drained the gas and put in new, cleaned the air filter, cleaned the deck, cleaned the exhaust plug. Mower still does not appear to have full power. What suggestions do you have for continued troubleshooting? Thanks  

Answer
Hi Bill,

On the exhaust, the muffler should be removed and the exhaust port cleaned.  The port may be filled with carbon.  The muffler could be clogged also.
Then, check the carb settings.  Make sure that full throttle is up to at least 3600 rpms or to factory specs.  Other than that, the only other thing I would do is disassemble and clean the carb or rebuild it if needed.

Let me know how you make out.
Michael