Small Engines (Lawn Mowers, etc.): kohler spec. #ps-41515, model cv15s, serial 2408816334 engine, throttle lever, cold weather

Question
when I start the tractor the engine runs at a high rpm. I have to turn off the tractor before the engine blows. The throttle lever doesn't do anything to slow down the rpms. If I pull on the choke lever the rpms slow down, then the engine backfires.  Thank you

Answer
mike

There are only two reasons for this to happen !

Too much fuel and two much air!!

Can be because the choke is not working (allows too much air) or the carb is not seated correctly (gap is allowing too much air)!

Fuel float is not working IE allowing full fuel flow!
On yours it sounds more like the throttle or governor is sticking wide open and the governor spring isn't strong enough to pull it back to where it should be. Clean everything up and make sure everything is working well and try it again. Could be the vibration of starting allows the weak governor spring to pull the throttle down but can't do it quick enough to prevent the over reving.

Does it happen everytime it starts or just when its cold? the cold weather will show you any weak parts on your tractor especially when it is hardest and coldest to fix.