Wiring Diagram for Key Start & 12 Volt Alternator Conversion

[AL Farmall Boy]

Ok....I just realized that I am gonna need a good wiring diagram for a Cub tractor that is "Key Start" and has the 12 volt conversion. I am re-wiring the 1975 Cub, and just realized that none of my wiring diagrams fit this particular set up. Hopefully someone out there has a nice diagram drawn up that they could share. THANKS!

[Don McCombs]

I'm not an electrical guru, so I don't know if this will be helpful or not...

[AL Farmall Boy]

Thanks Don, but I actually have that wiring diagram. That one is for the 12 volt conversion with a push/pull ignition switch and the pull start rod. I also have the wiring diagram for a "Key Start" 12 volt generator tractor; but I don't have anything for a "Key Start" 12 volt alternator conversion. I would try combining the information in the 2 different diagrams, but I'm sure that wouldn't work as there are probably differences in the wiring locations with an alternator instead of a genny with the key start.

[Boss Hog]

Just bolt the wire from the Bat terminal of the reg and the Light terminal to the one wire alt the rest stays the same as the key start gen

[AL Farmall Boy]

Hey Boss, I found this diagram in my "Tractor Computer" document library. I'm assuming I can treat this set-up the same as this diagram, and just go by it. Only concern I have is that the alternator seems to be wired a bit different than I have done and seen in the past (see wiring diagram previously posted in this thread). Would it still be ok to go by the diagram I have, but run the #2 wire to the BAT terminal on the ALT? Also, I notice they (the author of this diagram) used a ballast resistor between the #1 terminal on the ALT & the Key Switch. Is this for the same reason as the diode? I have diodes handy and would rather use one of those. Will that be ok?

THANKS SO MUCH FOR THE HELP!

[Yogie]

[Boss Hog]

I would call you but cant put my hands on the phone # , are you using a one wire Alt?

[Eugene]

I notice they (the author of this diagram) used a ballast resistor between the #1 terminal on the ALT & the Key Switch. Is this for the same reason as the diode? I have diodes handy and would rather use one of those.

The ballast resistor provides the same function as the diode or lamp used in other diagrams. It's to prevent the alternator from back feeding the ignition system. Use your diode if you have the Hitachi or Delco alternator with the 3 terminals.

I would call you but cant put my hands on the phone # , are you using a one wire Alt?

Exactily which alternator are you using? Do you use the hand lever, pull, to engage the starter or does your tractor use the key switch to activate a solenoid to engage the starter? Is there a neutral or clutch safety switch on the tractor and does it still work?