I’ve reread this thread and I think I’ve found your problem. You stated the the engine is not stock, which is probably the problem. Who ever installed the engine has not attached the control cables properly. The problem I have is that I’m not standing there to solve the screwup, and it will be very difficult to explain. Take a look at this video and then look at your engine again. Hopefully you will be able to reroute and attach the cables properly..two things I can see. The throttle control cable should go where the lower cable is attached. You will need to find a lever which controls the choke independently of the throttle. A good tech should be able to work this out for you if you run into problems, or come back with more pics of the controls and carb.
Interesting. Thanks so much! I'm positive I never changed that, previous owner must have attached it wrong. There were certainly other things he did incorrectly that I already fixed, so not a huge surprise.
Yes, in the first photo there are two cables running off the right side of the photo - bottom one is the choke control, upper is the throttle control. Then the wire running vertically is the link to the throttle control on the carb.
This is starting to make sense. I was wondering in the back of my mind how the governor could control the throttle when the throttle cable was essentially connected directly to the carb. But I hadn't made the connection that was where things were wrong. Thanks again, I'll watch the video you linked and see if I can get it together correctly and report back.