Alt, amp, and key wiring

Hello out there, I have a 1951 TO-30 and I need serious help in wiring the system! I have a Delco alt 12v, starter 12v, coil (not sure, no identification that I can see), amp meter (30 to 30), key switch (ordered from Yesterdays tractor for the to-30), and manual start switch. When I got the tractor it had a different start switch and a relay in the system. I wanted it back to original design and after a few years of being torn apart and not real knowledgeable in the electrical department I really need some help running the wires how they should be. I learn from visual and written instructions so if there are any pictures or diagrams that would be awesome. I have looked online and most have extra stuff in the systems so it confuses me in what I need to do. This is what it looks like right now.
cvphoto2047.jpg


cvphoto2048.jpg
 
Looks like you've done a very good job on the tractor!

Now, take your time and do the wiring right. I like to think the entire job through, get the lengths right so everything can be assembled in a presentable harness, secured away from snag areas, heat, pinch points, enough slack to allow easy access to the dash components. Route it as close to factory as possible. You can buy split plastic harness wrap at the auto supply in various sizes. It makes for a professional looking job.

Use low voltage fine strand automotive wire. It forms better, and is vibration resistant. Don't use house wire. I prefer soldered and heat shrink connectors. The crimp on will work, but the soldered connections are more secure.

Back to your original question, the original starter contacts carry the full load of the starter. There is no solenoid. The positive battery cable goes to one side of the contactor, then a short double ended cable to the starter. It is a good decision to keep it original, as that provides neutral safety start.

Here is a good wiring diagram. It it not for a Ferguson, but the same other than the starter.

Hope this helps, feel free to keep asking!
Wiring
 
go to fergusontractors(dot)org, resources, electrical diagrams.

There is a diagram for TO-30 12 volt with generator, and further down the list a diagram for Delco alternator that can adapt

Resistor in line from switch to coil indicates 6 volt coil. NAPA IC14SB (or equivalent)would be direct 12 volt that requires no resistor.

When rewiring be sure to keep diode or lamp in line from switch to small wire on #1 on alternator plug. This is to prevent alternator from feeding back to switch and coil allowing engine to continue running when switch is turned off
 
(quoted from post at 20:25:31 01/12/20) Looks like you've done a very good job on the tractor!

Now, take your time and do the wiring right. I like to think the entire job through, get the lengths right so everything can be assembled in a presentable harness, secured away from snag areas, heat, pinch points, enough slack to allow easy access to the dash components. Route it as close to factory as possible. You can buy split plastic harness wrap at the auto supply in various sizes. It makes for a professional looking job.

Use low voltage fine strand automotive wire. It forms better, and is vibration resistant. Don't use house wire. I prefer soldered and heat shrink connectors. The crimp on will work, but the soldered connections are more secure.

Back to your original question, the original starter contacts carry the full load of the starter. There is no solenoid. The positive battery cable goes to one side of the contactor, then a short double ended cable to the starter. It is a good decision to keep it original, as that provides neutral safety start.

Here is a good wiring diagram. It it not for a Ferguson, but the same other than the starter.

Hope this helps, feel free to keep asking!
Wiring


Is it ok to use 12gauge wire instead of the 16gauge? I have quite a bit of 12 awg type THHN/THWN and just a small amount of 14 awg. I have the 10awg for the alt to ammeter just wandering do I need to purchase the smaller size?
mvphoto47904.jpg
 
(quoted from post at 20:25:31 01/12/20) Looks like you've done a very good job on the tractor!

Now, take your time and do the wiring right. I like to think the entire job through, get the lengths right so everything can be assembled in a presentable harness, secured away from snag areas, heat, pinch points, enough slack to allow easy access to the dash components. Route it as close to factory as possible. You can buy split plastic harness wrap at the auto supply in various sizes. It makes for a professional looking job.

Use low voltage fine strand automotive wire. It forms better, and is vibration resistant. Don't use house wire. I prefer soldered and heat shrink connectors. The crimp on will work, but the soldered connections are more secure.

Back to your original question, the original starter contacts carry the full load of the starter. There is no solenoid. The positive battery cable goes to one side of the contactor, then a short double ended cable to the starter. It is a good decision to keep it original, as that provides neutral safety start.

Here is a good wiring diagram. It it not for a Ferguson, but the same other than the starter.

Hope this helps, feel free to keep asking!
Wiring

This is how I wired the system, does anyone see any problems?
mvphoto48159.jpg
 
Taking power for the ignition (and lights?) from the battery side of the ammeter means the ignition (and light) current will show up as a charge when the alternator is working, and not as a discharge when it isn't. Not necessarily a problem, everything else will still work except the ammeter won't be as accurate as it could.

Also, when I did this on my antique car, I found that the 30 amp ammeter would peg to the charge side after every start. It seemed to be slowly damaging the movement, as the needle started to stick. The easy solution is to change to a 60 amp ammeter; but I wanted to keep the original for appearance sake. So I came up with a shunt to recalibrate the original ammeter to roughly 60-0-60. Just a piece of copper wire, with the length chosen to match the resistance of the ammeter.
oOnqwEb.jpg
 
(quoted from post at 22:40:33 01/21/20) Taking power for the ignition (and lights?) from the battery side of the ammeter means the ignition (and light) current will show up as a charge when the alternator is working, and not as a discharge when it isn't. Not necessarily a problem, everything else will still work except the ammeter won't be as accurate as it could.

Also, when I did this on my antique car, I found that the 30 amp ammeter would peg to the charge side after every start. It seemed to be slowly damaging the movement, as the needle started to stick. The easy solution is to change to a 60 amp ammeter; but I wanted to keep the original for appearance sake. So I came up with a shunt to recalibrate the original ammeter to roughly 60-0-60. Just a piece of copper wire, with the length chosen to match the resistance of the ammeter.
oOnqwEb.jpg

So how should I wire that?
 
Sorry about the photo, I'm not sure why it came out so big.

To get the ammeter to accurately reflect only current to/from the battery, just connect the feed to the ignition switch to the alternator side instead of the battery side.
wzyUaUX.jpg


If you want to add a shunt to change the range of the ammeter, you'll need to do some detective work to find out how long to make the shunt.

One way to do that is to find some load (I keep old headlight bulbs for this sort of thing) that will produce some deflection on the ammeter. Then play with different lengths of shunt, until you get only half as much deflection. In this case, wire size does matter, the heavier the wire you use, the shorter it can be. I would guess, as a starting point, somewhere around 4" of 14 AWG would work. If that doesn't give enough deflection, use a longer piece (say 6"); or if it gives too much, use a shorter piece.

The shunt just connects across the two ammeter terminals, so that part of the current runs through the shunt instead of through the ammeter.[/img]
 
Thank you for that info, I thought about switching the ammeter to a 60 because of the alt. Have not decided yet. I did move the wiring to this.
cvphoto3223.jpg
 
From your picture you may or may not have to use a diode running the back feed power from terminal 1 on the alternator through the ignition resister usally kills enough power that the engine will shut down.
 

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