Well, I couldn't get the spec number to come up, but I looked it up on the John Deere site. It looks like you have hydraulic lifters,
you do not have Smartspark, but you do have a charging system and an electric pto. So you need to focus on your ignition as a culprit, so for starters, unplug the small wire going to your ignition coil and run it and see what happens, also have a spare good plug with you and plug it in if/when it dies again, and check for spark by plugging it in, and laying the metal side of the plug against the block and pull the rope quickly, and check for spark, you may have to remove the plug for a faster pull.
