8N Key Switch Wiring

[kuzie88]

I searched the forum but could not find my exact issue so I'm posting a new topic. fyi

I have a Ford 8N Tractor. I am not a mechanic and very little knowledge of wiring. But I do know how to add a wire and connect the ends.

My tractor's switch fell apart after sitting out all the time through the winter. It was a 3 or 4 post switch. So I removed it without taking a picture of where all the wires go. I bought (off amazon) a new switch with 2 post. I mounted the new switch and played around with the wires until it finally started (after a lot of trial and error). I thought everything was fine but the next day the (NEW) battery was completely dead, so I figured I have it wired wrong. A friend told me I should have bought a 4 post switch like what came off the tractor, so I did (see pictures). But I have no idea where all the wires go. There's about 4 or 5 wires, maybe 6.

I've searched and found many wiring diagrams online for an 8N but none are exactly like my situation, I don't believe.

My tractor has the distributor in the front. I'm not that familiar with what a terminal block or a resistor is, or even if my tractor has one. I believe my tractor is a 12v tractor.

If someone could tell me which wires go where I think I could hook them up. I "believe" I can track the wires to see where they come from (like from the solenoid or from the alternator, etc). I know nothing about a resistor or terminal. My tractor has 2 light switches and a starter button on top of the transmission.

I have included all the pictures (in no particular order) I think are relevant.

Any help would be appreciated.

Thanks, Mitch

[/img:e1f6e7af17]

 

[Bruce (VA)]

Does your tractor start with a key like a car, or do you have to press the starter button on the transmission cover?

It appears from that resistor that your tractor is 12v. Is it?

Google wiring diagrams JMOR and we'll go from there after you answer the questions.
75 Tips

 

[kuzie88]

I have to press the starter button on the transmission cover. I first have to turn the key in the ON position first.

12v

 

[JMOR]

(quoted from post at 15:12:53 10/31/23)
I have to press the starter button on the transmission cover. I first have to turn the key in the ON position first.

12v

f you can not sketch what wiring looks like and post the sketch, we will all be guessing, because it clearly is not as it left the Ford factory.


OK, my "guess":

This post was edited by JMOR on 10/31/2023 at 02:16 pm.

 

[kuzie88]

This is exactly what I needed. I will try to decipher this tomorrow when it's a little warmer (here in Tennessee).

Much thanks

 

[Eman85]

I would make a good guess that it is a 12V conversion as you posted a pic of the alternator usually a 12v.
Most switches you will buy are junk. I had a thread and Hobo has multiple giving the part #'s of the better switches available.
https://forums.yesterdaystractors.com/viewtopic.php?t=1603375&highlight=switch

This post was edited by Eman85 on 11/01/2023 at 08:09 am.

 

[kuzie88]

OK, I have few questions...

This first link below is the new (2-post) switch I bought and is currently installed on the tractor.
https://www.amazon.com/dp/B09M6BWD8Y?psc=1&ref=ppx_yo2ov_dt_b_product_details

I had a tractor guy tell me I needed a 4 post switch like what came off, which I bought (see original pictures)
https://www.amazon.com/dp/B0874B6G2Z?psc=1&ref=ppx_yo2ov_dt_b_product_details

Which one do I need or do I need a different switch than these?

 

[Eman85]

All the key switch is "switching" is the ignition so power in power out. What would you need a 4 terminal switch for if you have the factory starter button?

 

[kuzie88]

I have no idea. I only bought the 4 post switch because a tractor guy said I should. Plus that's what came off the tractor.

As a another note - the switch I have on it right now (2 post) works perfect, all lights work, etc. Only problem is the battery drains completely down over night.

 

[Mad Farmer]

I was just working on my TO-20 that has the same switch and 12V conversion.

It's wired like that except exciter wire from Alt goes to the start pole of the switch. When you start tractor, after starting, you bump key to start position to excite alternator. Alternator excite stays isolated from bat after that, no light/diode/resistor needed in that wire. The switch acc post is then free just for lights or acc's.

If you let someone drive the tractor tell them about starting up so the alt/bat is charging.

This post was edited by Mad Farmer on 11/01/2023 at 12:27 pm.

 

[JMOR]

(quoted from post at 14:28:40 11/01/23)
OK, I have few questions...

This first link below is the new (2-post) switch I bought and is currently installed on the tractor.
https://www.amazon.com/dp/B09M6BWD8Y?psc=1&ref=ppx_yo2ov_dt_b_product_details

I had a tractor guy tell me I needed a 4 post switch like what came off, which I bought (see original pictures)
https://www.amazon.com/dp/B0874B6G2Z?psc=1&ref=ppx_yo2ov_dt_b_product_details

Which one do I need or do I need a different switch than these?

ou showed a picture of a 4 pole switch, I tried to guess what you have, ....now you have wired for a 2 pole switch! Markup my drawing to reflect what you have as of now & post. If you do not want my help, keep listening to "what I have", and "why a 4 pole" and assorted comments that do not EXACTLY address your "how to connect like it was before I disconnected the wires?"

 

[Bruce (VA)]

So.......after all this.....you have a working two pole switch and the problem you are having is that the battery drains over night? Is that indeed your problem? Plenty of us
can help you fix that.
75 Tips

 

[kuzie88]

Yes, that is correct. I have a working switch but it drains the battery over night. I just assumed I had it wired wrong.

 

[JMOR]

(quoted from post at 17:10:16 11/01/23)
Yes, that is correct. I have a working switch but it drains the battery over night. I just assumed I had it wired wrong.

or a 2 pole switch, you probably do have it wired wrong.. ONCE AGAIN, how do you have it wired????????????????????????????????????????????????????

 

[kuzie88]

Ok, this is going to sound stupid but I assume you need to know where every wire goes, like what the 2 wires from the key switch are connected to and so on. And there's plenty of wires.

Note that I am no expert at tractors, and I for sure do not know how to wire a tractor - it was done when I got it. I did replace the broken switch with 4 post with a 2 post switch and I just guessed at that until it worked.

Let me know if this is what you need and I will get it tomorrow.

 

[JMOR]

(quoted from post at 18:33:13 11/01/23)
Ok, this is going to sound stupid but I assume you need to know where every wire goes, like what the 2 wires from the key switch are connected to and so on. And there's plenty of wires.

Note that I am no expert at tractors, and I for sure do not know how to wire a tractor - it was done when I got it. I did replace the broken switch with 4 post with a 2 post switch and I just guessed at that until it worked.

Let me know if this is what you need and I will get it tomorrow.

es, and most especially the wires that were on the old 4 pole switch....be sure to identify those.

 

[kuzie88]

Will do tomorrow.

Much thanks...

 

[DennyD]

On these tractors, there's no shortage of ways that sketchy old wiring can short or have impedance issues. Installing a battery cutoff switch (that you use religiously) can help to alleviate dead batteries for lack of new wiring.

 

[JMOR]

(quoted from post at 12:11:08 11/02/23) On these tractors, there's no shortage of ways that sketchy old wiring can short or have impedance issues. Installing a battery cutoff switch (that you use religiously) can help to alleviate dead batteries for lack of new wiring.

attery cut off can do that, but........................if there is a battery drain problem (as poster has), the batt switch is just a band-aid covering the problem. Best fix the problem. Batt cut off sw does have some value in terms of rodent chewed wires, fire prevention, etc., however.

 

[Mad Farmer]

What is exciter wire from alternator going to, and does it have a light/resistor/diode inline?