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Discussion Starter #1
I’m about to wrap up my battery relocation, and I am considering utilizing the OEM starter wire. Of course, the battery is now in the back, so I need a ring terminal that’ll support the amp draw. Does anyone know what size the starter wire is?
 

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Discussion Starter #2
To clarify:
The battery is in the back.
2/0 cable from kill switch to dist block.
2/0 cable from alternator to battery.
2/0 cable (ground) from negative post to engine block.
Oem wire from distribution block to starter.
 

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Discussion Starter #4
If it went to the kill switch, it would power the distribution block and the car wouldn’t shut off. If I ran the alt cable to the battery side of the kill switch, the car shuts off as intended, but it’s really no different than running it to the battery.

Do you know the size of the OEM starter wire?
 

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Discussion Starter #5
I took a minute to draw what I'm doing up for a visual, and I do not see any reason why this wouldn't work. I do understand running the alternator to the battery side of the kill switch, but running it to the battery would give it an opportunity to clean up the power coming from the alternator (I believe). Is there a reason the alternator should go the battery side of the kill switch instead of the way I have it? I am certainly open to suggestions, and it would be easy to move it..

 

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Josh,

I believe with a circuit built as you have drawn, opening the kill switch would prevent the starter from starting the engine but would not shut off a running engine. The problem is when the alternator is still in the circuit it can power the engine on its own after starting. In fact, once the engine is running you can even take the battery out of the circuit and the alternator will keep the engine running.

If you want the kill switch to shut off a running engine it must isolate the alternator from the circuit.

Nice clear drawing BTW.


Ed
 

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Discussion Starter #7
Thanks for the props on the drawing Ed. If you could, would you explain how the vehicle would stay running (with the kill switch pulled) if wired in the above drawing? The way I understand it, when pulling the kill switch, the power distribution block and the starter would lose all power and kill the car. The alternator's output would simply go to the battery. No voltage would make it beyond the inlet of the kill switch. Now, if the alternator cable was tied to the distribution block (like OEM), then the engine would keep running when the kill switch was pulled, but the two are effectively isolated in my drawing by the kill switch.
 

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Josh I did mine the exact way you depicted in your drawing. I also believe that if power is shut off to the distribution block the car will shut off. They key is not having the alternator feed the distro block.

To your original question, maybe I can dig up my oem starter wire and get the size of it since I previously replaced it with 2AWG wire. Why are you even touching the starter wire though? If it's connected to the distro block right now that should work just fine.
 

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Discussion Starter #9
Josh I did mine the exact way you depicted in your drawing. I also believe that if power is shut off to the distribution block the car will shut off. They key is not having the alternator feed the distro block.

To your original question, maybe I can dig up my oem starter wire and get the size of it since I previously replaced it with 2AWG wire. Why are you even touching the starter wire though? If it's connected to the distro block right now that should work just fine.
I am pretty sure it will work like this, and honestly, it won't be hard to test the theory when the time comes.

Please don't trouble yourself with digging up your OEM starter wire, I have one. I just don't know how to tell what size it is. If I were to guess, I would guess it's 6 or 8 AWG. I just started the thread to see if anyone knew what it was off hand. I didn't find anything during a search. Usually when the topic comes up, it's about what people replace them with, not the original size.

The reason I'm asking about the wire size, is that the OEM starter wire is not currently attached to the distribution block. As you know, this starter wire terminated into a battery terminal lug that I had to cut off. I just want to order up the appropriate lug (terminal ring) to finish up the connection. I haven't found any stores locally that have the size I'm looking for. The smallest copper ring I've found is 2AWG, and it's considerably larger than the OEM wire. The thread did take a turn towards the overall wiring, but that is perfectly fine by me.
 

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Discussion Starter #10
I picked up a 2awg terminal ring and did the deed. It's a touch big, so I'd guess the OEM size is 4awg. I was able to fold a bit of the braid over, cram it in there and double crimp it. I think I'm all set in this regard.
 

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Thanks for the props on the drawing Ed. If you could, would you explain how the vehicle would stay running (with the kill switch pulled) if wired in the above drawing? The way I understand it, when pulling the kill switch, the power distribution block and the starter would lose all power and kill the car. The alternator's output would simply go to the battery. No voltage would make it beyond the inlet of the kill switch. Now, if the alternator cable was tied to the distribution block (like OEM), then the engine would keep running when the kill switch was pulled, but the two are effectively isolated in my drawing by the kill switch.
Both you and Troy are correct Josh, I was wrong. Your wiring diagram, in fact, will shut off a running engine because as you correctly surmised the power to the distribution block would be interrupted, powering down everything in the car. The only alternator that could possibly still charge the battery would have to be a self existing (one wire) alternator. OEM Ford alternators are not, they require the presence of a 12 volt source to excite them. Remove the 12V source, the alternator shuts down and so does the car.

Ed
 

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I picked up a 2awg terminal ring and did the deed. It's a touch big, so I'd guess the OEM size is 4awg. I was able to fold a bit of the braid over, cram it in there and double crimp it. I think I'm all set in this regard.
Sounds good. What are you using to crimp? I'd usually say if you are using a terminal too small and forcing the wires inside you will not get a good crimp resulting in a poor connection hard to diagnose down the line. the same goes for a terminal too large which just causes the crimp to fail a pull test. I bought one of these cheap manual hydraulic crimping tools. There are a ton of different ones that look the same. I have yet to find a noteworthy flaw in the tool for the average DIY'er: https://www.ebay.com/itm/10-Ton-Hyd...319299&hash=item58e00663ca:g:lUAAAOSweXhXmHwZ

My only gripe would be the lack of it having a ratcheting lever.
 

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Discussion Starter #13
Below you'll see what I used to crimp this particular terminal with, however, I would really like to get my hands on that kit that you've got. I bet it does a pretty good job for things like this. That said, I my crimp(s) pass the pull test, so I am going to go ahead and "send it" for the time being.

 

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Just have to remember that the cable to the alternator is gonna always be hot. When you are working on it. Why I said "should".
 

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Discussion Starter #15
I honestly don’t know how this could be avoided. I mean, I could disconnect the battery when I’m working in that area, but anyway I map this out, the alternator has to be on the battery or the battery side of the cut-off.
 

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Josh,

In your circuit drawing, if you route your alternator hot wire to the starter hot wire, instead of back to the battery, you will not diminish the battery charging capability of the system. You will save the cost of the 2AWG cable to the trunk and you will also isolate the alternator from the battery whenever your kill switch is opened. The wiring is also much easier.


Ed
 

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Josh,

In your circuit drawing, if you route your alternator hot wire to the starter hot wire, instead of back to the battery, you will not diminish the battery charging capability of the system. You will save the cost of the 2AWG cable to the trunk and you will also isolate the alternator from the battery whenever your kill switch is opened. The wiring is also much easier.

Ed
The way I understand it, is that in order for the car to shut-off by opening the kill switch, I have to remove power from the distribution block. With that de-energized, the car will not run.

In factory trim, the positive terminal (that attaches to the battery post) contains two red power cables. One goes directly to the power distribution block and the other goes directly to the starter (solenoid). There is also a much smaller set of gray cables that goes from the alternator post to the power distribution block.

OEM Positive Wiring.jpg
 
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