Howdy, I've been a long time reader on here but haven't actually posted anything I think.
Anyways, we have a '66 4020 Diesel that I feel the need to do some rewiring on. I was in the process of doing a coolant flush and fix a leak and when I tried to go start it to move, it wouldn't start. I did some looking around under the dash and found out that the wiring situation is in pretty p**s poor shape with cracked and exposed wires every where. The original harness are gone, none of guages are hooked up, no lights, basically just a homemade starting circuit and that is it. The gauges and lights have never worked so long as we've owned the tractor so they aren't really a concern to me, although I am replacing the coolant temp gauge with the current work and I might try and convince my old man to get a new tach as well. As much as I would love to just order all new harness and have a fresh system, that is not in the budget. What I would like to do is wire up a new starting circuit and do it correctly.
About the tractor, I believe at some point it was changed over to a 12 volt system. There is an alternator instead of generator, and the battery cables are hooked up so that both positives run to the starter, and both negatives are grounded individually to the trans case. The alternator has a one stud and then a small plug with two wires coming out. I do have the service manual and have a fairly decent understanding of how the original 24 system works but then again it doesn't quite help me with the tractor being switched to 12v.
Could someone help me out with a good wiring diagram to accomplish this? One of the biggest things I don't know to do this is the correct wire gauge sizes to use and for what.
With the current no start problem I am having, I believe it is the key switch. I have ordered a new key switch and starting push button switch. I know the push button still works because it'll spark when grounded to the dash, and batteries are fine because I jumped the starter and it started up fine. But after seeing the condition of the wiring I want to redo it.
Thanks for any help!