I have a three year old LT 1045 with the Kohler 20 hp, It ran great the first year. Bought the little tune up kit and tuned it, drained gas, Maintained it in the winter. The next year ran great for about a month. started reving up and then almost dying, over and over until it began to backfire and stalled. would not restart until it cooled down. Thought maybe water in gas -no, unfortunately we had a drought that Year and I did not need it any more. This year I asked for help and got many suggestions, did them all. drained a cleaned the fuel system, replaced fuel filter, replaced all carburetor gaskets, replaced carburetor solenoid, replaced ignition and wire, replaced with new gaped plug, changed oil and filter. Ran great until it gets hot, about 1 hour then revs up and down and almost stalls over and over then begins to backfire and sputter and dies. It seems I spend more time working on than cutting with. About to stick an axe in it and leave it in the woods. Any suggestions?