surging

Howdy! I have a 2018 ZT 6000 w/the KT745 engine. At full throttle w/blades engaged, the engine runs smoothly. I do believe even at 3/4 throttle w/o engaging the blades, the engine is surging. I haven't worked on carbureted engines in many many years, so I'm here asking for some troubleshooting...

I see this issue on a daily basis and read about it on the forums. "My engine surges up and down".... So, you are standing there watching the engine run and surging up and down. The governor arm is rocking back and forth working the throttle, so it must be the governor, right? WRONG! The...