Small Engine Troubleshooting Problems? Ask a Mechanic Now.
What is the serial number of the genset?
If the unit is running for 20 - 30 minutes, then the problem is not going to be the governor control board.
This sounds more like the genset is starving for fuel.
Remoce the air filter.
Start the unit and let it run until it shuts down.
When it does shut down, immediately try to restart it while spraying in some carb cleaner (do not use starting fluid).
If you can get the engine running on carb cleaner, you have a fuel delivery issue, such as a clogged air vent in the gas cap, plugged fuel filter, dirty/collapsed fuel line, or a bad carburetor.
Connect a voltmeter and a frequency meter to the unit, and start it up. Make sure there is no load on the genset.
Monitor the voltage and frequency.
Also check to see if the red LED is on at the Engine Control Board.
What voltage and frequency do you get while it is running?
When it speeds up?
Is the LED on or off?
If on, does it stay on until the genset shuts down?