[R Bedell]

My Son-In-Law has a 2012 Cub Cadet LTX1046M that has about 225 Hrs on the Meter, and has a Kohler Courage SV715 engine in it.

A couple of weeks ago, he started having engine problems with it. When in normal mowing mode, full throttle and moving at normal speed, all is well. BUT.... when you slow down the tractor speed, to navigate a turn or go around a tree, etc, then engine will start to misfire, to include back firing. You press on the pedal to go forward and it goes away.

I took the tractor for a spin yesterday myself. It has described as above. I also noticed when you slow the speed down (reducing the load) and when the mis-firing starts, if you turn off the mower deck, the engine runs fine.

The S-I-L shot the Parts Cannon at it, and replaced the following:
* New Fuel Filter
* New Fuel Pump
* New Carb
* New Spark Plugs

Procedures done:
* Pulled the fuel tank and cleaned
* Bypassed the Fuel Pump to gravity flow
* Vented the Gas Cap

ALL of the above made NO difference.

So, I am seeing something happening when the tractor is slowing down, reducing it's load. At idle or full throttle, no issue. If you are mowing, as long as you don't slow down, no problem.

I am thinking, it might have something to do with the Governor. It may not respond correctly, to load conditions.

But, that is why I am here. I don't know that much about the Kohler Courage and looking for suggestions.

Please advise.