I have john deere L110 tractor, 350 hrs on it. Was running fine but now won't start. Changed spark plug but does not help. No spark it seems. It will crank up but won't start.

Remove the blower housing, then remove the small black wire from the coil and see if you get spark then.

Actually there was no ignition problem, it was able to spark. There was fuel getting to carbeurator. But the problem was in the carb. Bowl. There was water in the bowl & debri. Cleaned it out and cleaned out inlet into carb. Also cleaned out carb. With carb. Cleaner fluid and it was able to start back up once I put everything back together. Had to take off air filter.