Small Engines (Lawn Mowers, etc.): generator runs full wide open, engine shaft, time generator

Question
after running for the first time, generator runs full wide open. We have a PowerBoss 5500 watt generator, its about 4-5 years old now, engine model 204412 / 0163E1 / 050916YE

We used this generator for the first time, after 5 days of using on and off, running fine, it started to run Full Wide Open.

Opening the Governor System, we are able to adjust the speed by hand.

Do you have any suggestions on how to repair this issue?

We are wanting to get it repaired, will the manuel 276781 show us how to tear it down? We want to take the generator off to get into the motor, will the manuel show this?

Answer
   The Briggs manual will not show how to remove the winding, and that is always the big problem, to get it off the engine shaft
without damage.
    You would have to get the manual from the gen manufacturer
to deal with the winding.

The governor is internal, and no other way to get to it.