Kohler XT Series XT650 149cc 6.50 RPMs out of site

I have a Huskee push mower with a Kohler XT Series XT650 149cc 6.50 motor. I bought this last year (season) at Tractor Supply and it worked perfectly until we left for Oklahoma in October. Everything automatic, all I had to do was keep it in gas and pull the cord once to start it. I hired a person to keep my lawn respectable until we got back in April (mow my lawn 3 or 4 times). The person I hired to mow states he did not touch anything but the cord. I did allow my neighbor use it and she said it worked for a while however it reved up super fast and then quit. When I attempted to use it in April the RPM's were over the top. I took it to our local small engine (mower) repairman and he told me if this screw had been tampered with there was no way to repair the motor. When he fired it up it ran as it should. When I got home and started it up the RPM's went nuts again. I could not get it started again. Is this most likely the governor and is it repairable? I searched past threads but couldn't find anyone else with this problem.

Thanks for any help,
Miles

Could be the governor, but because the new engines don't have a throttle control the throttle is held full open by the governor when not running. Gas residue and various other sticky things can cause the throttle shaft on the carb to stick in the full open position.

Is there any way to free the throttle shaft without removing the carb? Probably no easy way to do this, huh? I'm not a mechanic but the good people on this forum walked me through a successful carb rebuild on my Ariens lawn tractor last year. Looking at the service manual it looks a lot more complicated on this push mower motor.

Cheers,
Miles

The IPL looks like 2 nuts hold the intake (back side of air filter housing) firmly to the carb. Intake should slide off. Then you are looking at choke plate and behind it is the throttle plate. Spray carb cleaner on both shafts and work them. I like to spray some lube or WD-40 in afterward, so upper cylinder isn't totally void of lube for first start.