There's an affliction common to the rural side of this country that attacks men more often than women, and the middle-aged or elderly more often than the young.
It's called "old iron disease," but you won't find it mentioned in any medical journals and no one that I've heard of is searching for a vaccine. It's one of those diseases, like "spring fever," that science has given up hope of ever understanding or preventing.
"Old iron disease" has nothing to do with blood chemistry or minerals, but a whole lot to do with memory and mechanical aptitude.
The first symptoms of the disease often appear at county fairs, farm equipment auctions or one of those antique tractor exhibitions. The victim will linger a little longer than normal over an Allis Chalmers Model D, or make repeated visits to a particular Farmall.
Retired farmers are particularly vulnerable to this affliction, but it's also seen in generous numbers of those hobby ranchers who have professional city jobs and a handful of country acres in pasture.
Look for the full onset of the illness once the victim arrives home with a John Deere Model B or something similar purchased at auction for just $2,500. Hours spent in the shop will immediately double and there will be persistent talk of PTO drives and three-point hitches and remote hydraulics.
Old iron disease isn't limited to antique tractor owners, of course. It also infects restorers and enthusiasts of gasoline engines, power units, motorcycles, steam engines, farm equipment, and just about anything else that has moving parts.
But old tractors have a special appeal, particularly the small ones constructed just after World War II.
International Cub. Ford Jubilee. Farmall. Oliver Super 55. Case VA-C. These were low-tech tractors with gasoline engines. They were built for the smaller farms of the 1940s and 50s. When crop production got more sophisticated and farms consolidated into thousands-of-acres operations, the little tractors were replaced by big diesel units and parked for decades in the equipment shed.
While thousands of these old tractors were scrapped, most were just mothballed or delegated to occasional duties. Unlike automobiles, tractors don't fall apart when they get older. With a little grease and some fresh plugs, they'll run as well as ever, and parts for most models are still plentiful. Lots of old Ferguson and John Deere and Allis Chalmer tractors are now employed mowing small acreages, cultivating gardens or pushing snow around in the winter.
Coming down with "old iron disease" may be awkward to explain, especially if you've spent a lot of your life lusting after the latest and biggest and most technologically advanced machinery. Some folks may call you up on this discrepancy in your character.
You could point out that as far as diseases go, this ailment is pretty benign. Tinkering with old tractors doesn't do any harm, generally, and it's better than taking to drink or gambling.
Hardest to explain, I suppose, is what you're doing with it out in the field or coming down the county road when there's no apparent work to be done. Just look serious, shout something unintelligible about the transmission while the tractors hums and sputters in neutral, then shift back into gear and keep on moving.