310g Diesel Wiring

[crwchf16]

Hi guys. So my 1966 310G needs basically all new wiring. This brings up 2 questions.
1. Does anyone make replacement harnesses? (Long shot, I know)
2. As long as I have to go this deep anyway, I'm thinking about replacing the generator/regulator with an alternator. Has anyone done this? What advice do you have?

 

[Tgrasher]

For the price of a harness, if there is one, you will do some hard thinking. Case had a color code for wiring, being your motor is a 188, here is a diagram for that engine on a 630 tractor. It's not that hard to make a harness, it just takes a little time and patience. Color becomes important under the dash as it tells which wire is which, and where it comes from. By uncovering a specific wire where it's undamaged you can find it's color. From there determine the length (add an inch or so) and solder your ends on with heat shrink tape. Harbor Freight has a box of terminals much more reasonable than anywhere else. I grind the plastic off and use just the terminal, makes a more professional look. By using solder you won't have any problems with the terminal in the future, on a 100 degree day when mosquitoes are on a feeding frenzy.

Assuming you would use a one wire alternator, eliminating the generator and regulator, the wire goes to the Amp gauge with a jumper wire over to the ignition from the same terminal. Most try to use the generator bracket with changes

to hold the alternator. Check your pulley sizes.

 

[WilBury]

Unless you do a lot of night work, you probably don't need an alternator. Those generators can still be had "off the shelf" a lot of places. I struggled with charging issues until I learned to polarize the generator (at the regulaor) every time the battery is disconnected. No biggie, at least on my 310E.
I think #10 size wire is called for, especially if alternator used, but I used #12 for my 25 amp generator circuit. Go for the nicest engine compartment rated wire you can find. Original harness has little numbered clips on the wire ends corresponding to the wiring diagram. I don't worry about color myself (except battery and preheat power) but I do mark the wires at both ends. Ensure good grounds at instrument panel, lights, (regulator ?). I'm fussy and use new star washers on bare metal. Do you have the shop manual yet? All the wiring diagrams are in there, including alternator. Like Tgrasher, I take the plastic off the crimp terminals and use with shrink tube but I didn't bother soldering. I like the heavy duty yellow terminals with the black stripe. I really like the clear/white spiral loom wrap and zip ties where needed.
As said, it does take a good bit of patience and maybe a few redoes. I've done the whole harness twice. I'd go for an extra foot, gives you room to make a neat job of it. Don't terminate the other end till you're satisfied with the look of it when bundled in place. Use a new starter switch while you're at it...