Maybe I'm in the minority with this perspective, but I'd say that 17 hours over the course of 4 years could constitute abuse. In my opinion, sitting around not being used is not helpful for equipment. Maybe old purely mechanical stuff doesn't suffer as much, but a modern deluxe model tractor like we're discussing here has lots of electronics. When stuff doesn't get used it deteriorates. The problem could be from corrosion, or possibly from mice or other varmints chewing wires. If you don't use the machine regularly, you should inspect it for mouse activity before firing it up.
I hope this isn't taken as rude, but perhaps the OP would be better served by renting a tractor for the occasional need. After only 17 hours in 4 years, it's probably safe to assume that the rings aren't even seated yet. Has this machine ever been run long enough to get the oil hot enough to remove condensation? Oil should really be changed annually on tractors (with some exceptions I'm sure), despite the amount of hours on the clock. So, the OP should have completed at least 3 oil changes by now. Also, a machine that's used in this manner will probably draw some scrutiny during resale. I'd probably rather buy a 10 year old machine with 1000 hours than one with 40 unless there was a darned good reason for it to be that way and proper steps were taken to store it.
