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Discussion Starter #1
2N died on me plowing snow with a 3 point blade. I was finally able to take a look at it. The points melted, not the metal but the plastic arm where the contact is. This I think in turn fried the coil. Any idea why this happened? Over voltage maybe? Cheap points? I've never seen a set do this.
Tractor has front mount coil, 12 volt conversion using the Genny and 12 volt coil with oem resistor.
Thanks for any help.
IMG_20210222_130140665.jpg
 

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Several questions:

How recently was it converted to 12 volts?

When were the points and any other ignition components replaced last?

When the plastic melted were the points stuck open or closed?
 

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are you sure you have a 2n not a 8n or a 9n? 2 n had magnetos and hand crank 9n had generators and battery's 9n's also had 3 point hitch mounting
 

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Change points/condenser and resistor (dont think 6V had resistor) to Pertronix Ignitor, put one on my Oliver Super 55, now it starts every time no more oxidized points.
Edgar
 

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Discussion Starter #6
It was "converted" a little over a year ago. It was not a "proper conversion" the guy did it right before I bought it. He added the 12v neg ground battery, the Genny is a 3 brush that was adjusted to make it charge 12v and a 12v coil. The points, condenser, cap, rotor, wires and plugs were all done by me when I got it. It burned up one coil a while back when a friend borrowed it. Then it died on me when plowing snow. It sat for a few days til I was able to work on it. That's when I found the melted points. They failed in the closed position which I think might be why the coil burned up this time. The springy contact was roasted.
I ordered a new points plate with points and condenser, should be here tomorrow. I ordered the plate because the screws were getting worn and it does not have the correct brass screw for the coil contact.
As far as being sure it's a 2N, not completely. I looked it up on tractor data and thought that's what I read. I could be wrong. It does have electric start and 3 point hitch, rubber tires as well. Serial number is 9N215137.
Oh, and the resistor I mentioned is the oem type behind the dash.
I eventually want to do a rewire on this thing but right now money is tight, just got back to work after 3 months due to a knee injury.
Thank for any help. I appreciate it
 

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6 to 12 v on a ford is not fun ,i did a 33 woodie wagon last year 6 v positive ground to 12 volt neg, if asked again i would say nope!
 

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Discussion Starter #8
From what I've read on these 12v conversions the ignition become the biggest issue. I just want it to be reliable. At this point I don't have a good 6v battery to go back. I have an 8v battery somehow. Lol
 

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I think your SN refers to a 1946 2N.

It has been around 75 years and who knows what has been done to it before you. Just be sure that points, condenser, coil, and resistor if so equipped, are all for a 12 volt system.

Melting a contact mount almost sounds like the points somehow got grounded out, applying 12 volts to ground through the point contacts. This would be sort of a long shot, but be sure something hasn't grounded out to the distributor body, or a cracked wire where snow or water migrated and allowed a short to exist, melting your plastic point contact mounting.

If all checks out ok, replace with all 12 volt parts. See what happens.
 

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Discussion Starter #10
What resistor will I need for a 12v coil then? I have a new 12v coil just waiting on the points plate to out her back together. I read different things online concerning resistors with a 12v coil, some say to use the oem behind the dash, some say to use none at all.
When I disassembled it I didn't see anything to lead me to believe it shorted to ground.
 

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I have 4 8N's and a 2N. All of them are 12v with alternators. People will always say to just leave it 6 volts, but my theory always has been that if 6 volts was so great, then why in the world did everything go to 12 and stay there? Your 8 volt battery is an attempt to get more energy in a 6 volt system without switching components. Used to be a super common thing to do. Not so much anymore. We only have one 8 volt battery left on our farm. In an AC WD. Pain to charge, that's for sure.

As someone else said, if you can afford it, the electronic ignition kit is the way to go. I have 2 of my 8N's set up this way and they are dead reliable. The new aftermarket coils for these tractors are not very robust and are prone to failing if they get the wrong voltage or just get too hot. I literally have dozens of dead ones in my barn (we have had 8N's on the farm since the 50's) Also, some of the coils are internally resisted and some are not. Ones that are not internally resisted DO require an external resister, but your ballast resistor under the dash may not actually be enough or it may be too much. I have found a huge range in the actual measured resistance of those ballast resistors. Especially the cheap replacement ones. Your best bet is to make sure that the coil you buy does not need to be externally resisted. Then you can either remove the ballast resistor or bridge it (I bridge them by making a short piece of wire with eyes on each end and connect it to the terminal on each end of the resistor. That way they wiring harness doesn't have to move.) My 2N is still running stock breaker point ignition on it. I have a belly mower mounted on it and it does fine, but it never has to work hard. One of my 8N's is a side distributor (that was the best thing they did for these tractors) and my remaining 8N that I have at work has the typical Ford ignition woes. Someone hacked a 12v system onto it and it's a roll of the dice as to how it will start and run on any given day.

If you are lucky enough that you can get your hands behind the radiator and swap components without pulling the hood and radiator, then swapping ignition parts isn't too terrible bad (still a pain though) I inherited one of my 8N's from my grandfather and he could swap the coil out in about 2 minutes (I have the pile of coils to prove that he did it pretty often) My hands are too big to do that so I have to pull the hood and radiator. After the first time you have to do that in the middle of a hay field in July, the cost of the Pertronix electronic ignition kit seems like the best bargain on the planet.

Edit: Just out of curiosity I looked at a dozen or so different 12v coils for sale. Information on them is terrible. Half of them say no other resistor is required and half say to use the ballast resistor. The coil I have on my 2N specifically said to remove or bypass the ballast resistor and run 12v straight to it. I have never had any issues with it for 6 or more years now. I thought I bought it from Steiner, but the one on their website says to use the ballast resistor as well. My advice would be to make sure you have a wire going straight from the ballast resistor output to the coil (guys used to put a large resistor in line with the ballast resistor to drop the coil feed to 6 volts so they could run 12v battery and alternator and not have to swap any ignition components.) Set your points and install your new condenser and the new coil. A coil gasket extends the life of the ignition by a large factor. We even use silicone on the seam between the cap and the coil after everything is installed to keep out dust and moisture. It really makes a difference. After you do all this and get it going and working again, I would start looking into an electronic ignition kit and replacing the breaker points and coil. You will be much happier with it in the long run.
 

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I would ditch the generator too. A cheap GM one wire alternator will do you much better and be more reliable. And yes, people will try and shame you for running a one wire alternator saying that a 2 wire is simple to hook up and run, but unless you are going to put a charging light on the dash, there is no need for anything more than to charge the battery. Last piece of advice, pull your ammeter and put it on the shelf and replace it with a volt meter. You will be able to monitor your battery status better and you wont have the potential to have the 70 year old ammeter short out and catch on fire. Ask me how I know. Twice.
 

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Discussion Starter #13
Thanks guys! Great advise.
I have mini one wire alternators on two of our Farmall tractors, those seem to work we'll and nice and compact. They are rated at 45amps I believe. I think one of those will be in order for the 2n as well.
I will look into the electronic ignition once money allows also. I don't use this tractor alot but it does have a front loader on it that comes in very handy at times and was repainted a while ago so also looks pretty nice. Fun to drive, just need to modify the seat. I am tall, the seat position is horrible for me. It needs to go up and back somehow. That's another thread on another day.
Once I get the distributor back on I will check the amps going to the coil to see if I will need the resistor. I believe I've read that between 3-4 amps is acceptable?
Checked the coil, internally it had 8.06 ohms between the springy terminal and the flat piece. 1.2 ohms from the top terminal to the springy term.
 

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Thanks guys! Great advise.
I have mini one wire alternators on two of our Farmall tractors, those seem to work we'll and nice and compact. They are rated at 45amps I believe. I think one of those will be in order for the 2n as well.
I will look into the electronic ignition once money allows also. I don't use this tractor alot but it does have a front loader on it that comes in very handy at times and was repainted a while ago so also looks pretty nice. Fun to drive, just need to modify the seat. I am tall, the seat position is horrible for me. It needs to go up and back somehow. That's another thread on another day.
Once I get the distributor back on I will check the amps going to the coil to see if I will need the resistor. I believe I've read that between 3-4 amps is acceptable?
Checked the coil, internally it had 8.06 ohms between the springy terminal and the flat piece. 1.2 ohms from the top terminal to the springy term.
If your coil only gave you 1.2 ohms on the primary side then that may be your issue. That would most likely be a 6v coil and not a 12v coil. A 12v coil should have closer to 3 ohms. If you run a 6v coil on 12 volts you will be guaranteed to melt points every time. You may have just solved your problem.
 

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Also......... as to what model of tractor you have 2N vs 9N. It has NOTHING to do with steel wheels and magnetos and hand cranks or drawbar only. Yes some 2Ns came that way, but they are rare. If it was the first series built starting in 1939 it is a 9n. In 1942 Henry Ford wanted to raise the price but due to the war, prices for existing equipment was fixed. New equipment could be priced at current market value though so the SAME tractor was re-introduced in 1942 as a 2N. A 2N has casting marks all over it that say 9N. Due to war rationing, some 2N's did get magnetos and hand cranks and steel wheels and no hydraulics. Just like every other tractor manufacturer had to do. In 1948, the 8N came out and it actually was an updated tractor. A 2N and a 9N are the same thing. And before someone starts to talk about round radius arms vs. I-beam arms, that had nothing to do with a model change. The early 2N's had I-beam radius arms too. That was changed after the 2N was already being sold.
 

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Discussion Starter #16
The coil I have says 12v on it. Could this new coil be bad? Wouldn't surprise me much if it was. Lol
 

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The coil I have says 12v on it. Could this new coil be bad? Wouldn't surprise me much if it was. Lol
Wouldn't surprise me either to be honest. I have been down that road more times than I would like to admit. I am by no means an expert on this, but I have been dealing with these tractors all my life. (And I teach this stuff for a living) Your goal of a 3 to 4 amp draw at the coil is on the mark. Usually 3.5 is as high as you want to see. Ohm's law states that current is the direct result of voltage across resistance. I=V/R. Do some algebra and that means that to find the necessary resistance you will take the voltage and divide it by the current. So if you have between 12 to 14 volts from the battery and you need 3.5 amps at the coil, you will also need about 3.5 to 4 ohms at the coil. The ballast resistor on your dash SHOULD hit 1.5 ohms when it reaches temp. It will be maybe as low as .5 ohms on start up. (I have never found old ballast resistors OR new aftermarket ones to be a reliable number without measuring them) So running if your coil has 1.2 and the ballast resistor is working perfectly at 1.5 you are still operating at 2.7 ohms which with an alternator putting out 14 volts (or in your case a generator that has been turned up) you will be getting 5 amps at the coil which will eventually overheat it. Not immediately, but as you found out (and I have many, many, many times.....) work it hard for an extended period and the coil is dead. IF the previous owner bridged the resistor, or the resistor is shorted internally, or it doesn't reach a full 1.5 ohms, your amperage will be even higher. Measure your ballast resistor and see what it says. You will have to have current running through it for a minute or so before it will reach peak resistance. I was trying not to get too complicated before. Hopefully you can follow that.

If possible, try to find a square coil that has a 3 to 3.5 ohm internal resistance and be done with the ballast resistor. I am sure that is what I am running on my 2N although for the life of me I cannot remember where I got it. If you cannot find one, or you just want to use the one you have, you could try adding another .5 to .75 ohms of resistance to the wire going to the coil. Off the top of my head, I wouldn't be able to tell you what exact part you could use to get this, but if you know how to use your meter, then you can figure it out. Also, if your generator is over charging due to being turned up, your amperage will rise accordingly.
 

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Discussion Starter #18
That helps alot actually, I will measure the amperage with the key on point closed and see where it lands. I don't know what to use in line if I need more resistance but I'll figure something out.
 
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