Check here for a service manual for your mower:
Never mind. This software eats the URLs and provides error codes.
Or go to this site and get the manual factory direct:
Never mind. This software eats the URLs and provides error codes.
Where you can select the model/hp/orientation and get the correct manual.
Your (and my) engine models are discontinued or 'retired', so follow that path.
I would check that the linkage allows full throttle. The governor is connected to the carburetor by a lever to the right of and behind the carburetor. The lever will sit almost vertical at rest. It will move as the hand control is moved from slow to fast in response to the spring. The lever should allow the throttle to open fully. You can figure direction for full by moving the control. As you move to fast, the throttle plate will try to open. Watch as you move the control, and going in the same direction, verify you can move the throttle plate wide open, and the governor does not limit the movement.
If you have not already done so, check there is not sediment in the fuel tank, the filter is working, and the fuel line is not falling apart inside. If you have a pump, the pump should flow fuel right away when you crank the engine a bit. If gravity, the fuel line should flow a full-diameter stream just by gravity. If not, check further.
tom
Go to my tractor forum dot com for better information and a pile of people who can help. I am done wasting my time on this site. That didn't take long.