BN 12volt conversion?

I have a Farmall Bn and when I purchased it someone had already switched to twelve volt. But the conversion had been done horrible and all the wiring is gone. I want to redo it but I am unable to find a kit. I need all new wiring for sure and a new alternator and some direction! Can some one help me out.

Mike

Bob M has the best wiring diagrams you'll find!!
Bobs Wiring Diagrams

Yes. Bob M wiring diagrams will do what you need. If it has a magneto ignition, things get a little harder, but not much.
A mag is grounded to make it stop, and ungrounded to run. THus there is no voltage going to the mag at all, and cannot have any ever.
So to make the alternator excite, I would use an oil pressure swithc fromNAPA to make it work The switch has two terminals, and is open when there is no pressure, closed when there is about 3 psi.
This oil pressure switch is placed in series with the positive side from the battery. Run a #14 wire from the starter switch on the starter (big terminal attached to the battery cable) to the oil pressure sw, then to the #1 terminal of the Delco SI alternator. The #2 terminal attaches directly to the bigger output terminal of the alternator. The output terminal attaches with #10 wire to the terminal of the amp meter that is not connected to the battery pos post (usually at tha same place on the Starter sw that I refered to before. The wire just mentioned (from amp meter to battery at starter should have a fusable link wired into it near the start switch at the starter. NAPA has fusable links; they protect all systems from letting the smoke out. THe fuse link should be rated at 10 amps over the rating of the alternator you use. (often stamped into the alternator housing)
A Hitachi alternator from a mid 80s nissan PU will be smaller and put out plenty It is wired similarly. THere are many descriptions of the Hitachi in the archives to use for terminal marks. Good luck
Bob M wonderful diagrams

If you get an owners manual it will have the system in the back how its wired if you want to return to 6v as a BN sure doesent need 12v.

Can I set my 12 volt up on the BN the same way as the Farmall M diagram? And I am going to 12 volt due to the winch for the snow plow. Thanks for your help.

Mike

Bilko, read this. I converted a IH 240 U using this information. David.............

http://www.ytmag.com/articles/artint131.htm