Converting My 6 Volt Tractor to 12 Volts

If your tractor runs well on its original 6V, there's no compelling reason to convert, though doubling the voltage can put pep into the ignition system and gives you access to a much wider range of accessories. 12V add convenience, though. A 6V tractor can't be jump-started from a 12V vehicle, and every car battery charger supports 12 V batteries, but few support 6 V.

Like a lot of people, I converted to 12V when my tractor needed expensive electrical repairs. In my case, this was when my generator gave out. The generator worked worse and worse, and when I took it apart, it was a wreck. Fixing back to the way it was wouldn't cost much less than converting it.

I bought a conversion kit from Walt's Tractor Parts, and was very happy with it.

There are so few parts in a tractor's electrical system that it all went very smoothly, though I accidentally wired the ammeter backwards and have never gotten around to fixing it. The "wiring harness" only has four or five wires in it. The kit includes a new one. This stuff ain't rocket science.

A lot of the tractor's original parts can be kept -- the original starter, starter solenoid, ammeter, ignition key, and (usually) ignition coil are retained. The generator and voltage regulator are removed and replaced with an alternator with a built-in voltage regulator. You need to replace the battery and the headlights.

My kit came with a resistor to use in series with the old ignition coil. A lot of 12V ignition coils also use an external resistor. In the end I replaced the unit with a 12V coil with an internal resistor just to simplify the wiring a little.

I noticed that the alternator doesn't do anything until the tractor gets up to around 1,200 RPM. This isn't very important unless you idle it at low speeds for a very long time after starting it. But don't be surprised, when you do the conversion, if the battery doesn't charge until you get the RPMs up. Once the alternator kicks in, it keeps going even if you run the engine down to very low RPMs.

One problem that the 12V conversion didn't help was the difficulty I had with my starter, which didn't always engage. This was due to a damaged ring gear. It's possible that running the original starter motor on 12V accelerated the process of ring-gear destruction, though I had been having trouble with it before the conversion, and it was probably a goner in any case.

When I had the ring gear replaced (an expensive process, since it's quite inaccessible), I also replaced the starter motor with the 12V model. It probably wasn't necessary, but it made me feel better.

By the way, if you like the idea of keeping your tractor in stock condition, you can replace 6V generators with 12V generators that look just the same. At least, you can do this with Fords. Ask your dealer. I have no interest in keeping my tractor looking original. Not if it means using that horrible metal seat!

Next: You Gotta Have a Comfy Seat

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