In Reply to: 6 to 12 Volt Conversion posted by Daniel Jinkins on October 14, 2018 at 05:25:50:
Welcome aboard the NTC! You'll find a wiring diagram in our HOW-TO's forum -see LINK below as well as many other useful technical documents you can download for FREE. Scroll all the way the bottom to see the NAA 12V conversion. There are about half dozen correct ways to switch over, and a hundred or so incorrect ways often done by fellas who have no clue what they are doing. There are also about a half dozen good reasons fort switching and a half dozen reasons why not too. First, we all know it is your tractor and you can do anything you want with it. Switching a 6V/POS GRN system over to a 2V/NEG system is often thought of as 'fix' for a non-starting/non-running tractor. It isn't. If it doesn't start now on 6V it isn't going to on 12V. You also need to know that 99.98% of all non-starting issues are due to incorrect wiring, regardless if 6V or 12V. Most of those issues are due to an incorrect 12V switch over job. Find copy of 75 Tips For N Owners, and download copy as well as wiring pictograms to start with before you decide anything. If you are having non-starting issues now, look at this electrical system wiring diagram from the Operator's Manual and verify what you have is correct for a 6V/POS GRN system. A lot of issues are also due to an old battery that won't sustain a charge anymore. If it is 5 years old or more, chances are it will no longer hold a charge as the electrolyte is all depleted. Your local starter/alternator shop can bench test it for FREE usually. Start with these points first.
FORD NAA, 600, 800 ELECTRICAL WIRING SYSTEM, OEM 6V/POS GRN:
FORD NAA 12V SWTCH OVER –COURTESY OF JMOR & JUST8NS: