John Deere LX255 problems

[samcarpen]

Kohler CV15S 41571 3107308921. Began not re-starting when hot. Now won't start at all. Back fires through carb and exhaust. Introducing fuel through carb bore has no effect. Carb solenoid is clicking and flywheel key appears intact. Has anyone dealt with this problem with this engine?
Thanks, Sam

[Gerry]

Check for spark before and after the plug, sometimes backfiring thru the carb indicates a valve problem.

[hanz63]

More commonly an ignition coil failing on these. Some will even have spark yet, but the CD throws the spark out of time. There are a few that exhaust seats come loose but generally aren't very repeatable following up with a good cold start.