I'm working on a troy-bilt tractor with a kohler courage 18 (model # SV540S). The owner said it was hard to start and did some messing with lord only knows what. Long story short, I got it and rebuilt the carb, cleaned it up and it starts but the throttle controls wont work right. most of the time it runs wide open no matter where the throttle is set. I've tried adjusting the governor and twice i got it to idle normally but it wouldn't throttle all the way up it would barely increase rpm's when the throttle was pushed up. I can manually open and close the throttle plate and the engine will react appropriately. Is the governor bad or is there a special way to set it on this engine? I'm trying to exhaust all other options before telling my customer that the governor needs to be replaced.
I think the owner might have bent the rod that links the governor arm to the throttle plate, and the spring on the same arm appears to be tampered with. Could this be the issue or do i have a bigger problem?