Kohler engine surging
I took out dad's Gravely from winter storage, sharpened the blade and started cutting grass. It was running smooth, then about 5 minutes in, the rpm started surging. It idles just fine. It surges anywhere above idle. If I hold the throttle on the carb, the engine smooths out and just hums. I am assuming this is a problem with the governor, but have no idea where to start. I can't find a thread on this, so I must not be selecting the correct search parameters.
It is a Gravely 5260 according to the hood, I could not find any other plates on it. The engine is a Kohler
Ser # 8250569
Thanks in advance for the help.
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