I have a 1962 A/C D-15 tractor.
What is required to change the tractor from a positive ground to a negative ground??
What was the advantage of a positive ground back when they were manufactured?

Some makers thought it saved on frame corrosion. Otherwise it works no better or worse than negative ground.

To change it you need to change the battery cables to fit the posts right, then you swap the connections on the ammeter if there is one, and the ignition coil if gas. You must flash the generator before starting the engine so it will charge with the correct polarity. If it has a radio you must change its polarity. Radios that worked with positive ground often had a plug to change polarity, or if vibrator sometimes the vibrator should be reversed in the socket to change polarity.

You will confuse the next owner who reads in the owner's manual its positive ground unless you add a sign to say its been converted to negative ground.

Everything works either way, even jumping so long as you keep the battery polarity in mind when hooking up the jumpers and don't touch chassis together. And when charging a positive ground some chargers will short the battery if the charger case touches the tractor frame or tin work.

Gerald J.

Thanks Gerald...
It's not giving me any problems.
I'm just rewiring the tractor and thought of changing it over as an after thought.
Maybe I'll just leave it well alone.
I appreciated your reply.

Kelly

I have all 3 of my tractors on pos. ground and I don't get corrosion on the battery posts at all.

Dennis

I left mine Pos ground because I hate wiring! Don't know why, and I'm probably in the wrong line of work but oh well.

We have a 1963 D-15 Series II. It's always been positive ground with no issues and no corrosion. After you clean the battery terminals well, spray them with clear acrylic spray to keep essentially all corrosion at bay. It works great.

If you change it, you're in for a lot of unnecessary work, in my opinion. Good luck with your project, Kelly!

Tom

Thanks Tom....
I'm actually going to leave it alone. Just replace all the cracked wires and clean up all the connections.
I'll post pictures when the dust settles.