Engine speed mystery
Check the jets in the carburetor. I have a Kawi FC150 5.5hp on my 21" Toro. After checking the spark plug, governor linkage, fuel
filter, etc. I still had the same problem. Talked to the mechanic at
the Toro dealer and he suggested that I check the governor gear.
Ordered the parts and opened up the engine. NOT THE GEAR!
All that was left was the carburetor. I dismantled the carb. and
discovered the jets were dirty, After cleaning and re-installing, the
engine runs great. I have ordered new jets, and will replace them.
This engine is 4yrs. old and gets many hours of use per week.
Hope this helps with your problem.