my neighbor has a Huskvarna tractor (2011) with a Kohler courage 25 engine. It starts fine and runs 20 - 30 minutes and shuts down. Once it cools off it starts again. I saw another post that said it may be the coil. What's wrong with the coil?
would check the fuel tank cap vent for being blocked up first... clear it by probing with an unbent paperclip and blowing out with compressed air to clean out any trash. Try running machine again.