Farmall B electrical issue

[FarmallB1945]

Hi all
I recently was running my Farmall B, when I had shut the tractor off I had noticed there was smoke coming out of the electrical box below the throttle assembly. After I started the tractor back up to pull it in the shed to further investigate what happened, it ran just fine for that short while then unhooked the battery and let it sit for a day. When I came back I found that the wire coming from the relay on the generator had been burnt. I also started the tractor again to find out it was missing on different cylinders. I pulled the distributor apart and found that it was making poor or no sparks when it should be. I am stumped and appreciate any help you are willing to give.

 

[Janicholson]

The wire may have had a short to ground, I would replace it with 10gauge wire and go from there. The wire should go from the Bat terminal on the cutout, to the ammeter (non battery side). Jim

 

[560Dennis]

mice Love that control box condominiums, chew up my wires on the Farmall c .
as suggestion, replace wires that are damage with new according the wiring diagram . Wire guage s are convenient listed on the wiring diagram. any wire thats the cooper is burnt color or corrosion green should be replace,
also the grounds a critical, it is positive ground system,
if the battery cables are green with corrosion should be replaced with heavy duty ,0-2-guage wire ,the are very important to the tractor electrical system operation .
I recommend take cover of the clutch housing torque tube inspection for mice nest and vacuum out the mice nest from .
i recommend puttin some green pieces of Irish spring soap bar in the there. It will keep the mice out for a while ,.

 

[wore out]

Hi all
I recently was running my Farmall B, when I had shut the tractor off I had noticed there was smoke coming out of the electrical box below the throttle assembly. After I started the tractor back up to pull it in the shed to further investigate what happened, it ran just fine for that short while then unhooked the battery and let it sit for a day. When I came back I found that the wire coming from the relay on the generator had been burnt. I also started the tractor again to find out it was missing on different cylinders. I pulled the distributor apart and found that it was making poor or no sparks when it should be. I am stumped and appreciate any help you are willing to give.

Sounds like the "cutout" may have stuck when the engine was shut down, backfeeding current through the charging system.

 

[used red MN]

I pulled the distributor apart and found that it was making poor or no sparks when it should be.

Hello Farmall B guy, welcome to YT! How did you determine that the distributor was “making poor or no spark” by disassembling it? Seems like an odd method to me. To determine what type of spark a distributor is putting out it generally has to be mostly assembled and you test the output of the high tension wires (coil and spark plug wires) by determining if the output spark can jump a 1/4” gap. My guess is that the points may have just been on their last legs so to speak and maybe the battery had lower voltage after the short out episode so it didn’t run correctly. It would be helpful to know if you have a magneto or battery ignition with a coil. The above assumes it is a battery ignition.

 

[FarmallB1945]

I’m sorry I could have phrased that better, I took the top of the distributer off to see the spark the distributer makes, I will link a photo below so you can see what I mean. This is a battery ignition tractor with a coil. Thankyou all for your input, it is very much appreciated.

 

[Jim.ME]

I’m sorry I could have phrased that better, I took the top of the distributer off to see the spark the distributer makes, I will link a photo below so you can see what I mean. This is a battery ignition tractor with a coil. Thankyou all for your input, it is very much appreciated.

It may just be the picture but the point contacts do not look good to me.

Be sure the condenser wire hasn't worn through and grounded inside the distributor, I've seen that happen.

With the cap on the distributor and everything hooked up. Tractor in neutral, test light grounded to the block and the probe on the coil terminal that has the wire going to the distributor, try to start it. Does the test light flash on and off as the engine cranks over?

 

[used red MN]

I’m sorry I could have phrased that better, I took the top of the distributer off to see the spark the distributer makes, I will link a photo below so you can see what I mean. This is a battery ignition tractor with a coil. Thankyou all for your input, it is very much appreciated.

Looking at the “spark” at the contacts of the points in the distributor is one of the most misunderstood and misinterpreted things that happens when someone is diagnosing what is wrong with their distributor ignition. What you are looking at there is not “the spark” it is simply the “arc” of electrons of current as the points break contact, much the same as you see when you pull a plug out of an outlet in your home that has a fair load on it. Are you familiar with the Star Trek character Data? You would have to possess some of his unique capabilities to actually assess your ignitions functionality by looking at the arc, essentially your eyes would need to turn into an oscilloscope, enough on that. (Edit to add: It is the condensers job to “soak up” the electrical surge when the points open to limit the arcing or burning of the contacts of the points) Here is a link to a better way to check the actual high tension spark that is produced by the interaction between the magnetic field of the primary winding (connected to the small external terminals) in the coil and it’s secondary winding when the magnetic field in it collapses when the points open. Adjustable spark tester
Set that to a 1/4” and test away. The 1/4” is due to the fact that when the spark gap of the spark plug is under compression it takes more voltage for spark to jump the gap.
I see the tractor no longer has stock wiring, give us a photo or two of the wiring that burnt up.
IH ignition info This might be helpful to you if you are interested in learning more about how your ignition system works.

 

[FarmallB1945]

This is the wire that burnt out, it goes to the relay on the top of the generator.

 

[grandpa Love]

This is the wire that burnt out, it goes to the relay on the top of the generator.

First thing we do with any "new" tractor is replace the wires....most are terrible .if everything works, do one at a time,if nothing works ( more common for what we buy) we cut everything off and rewire it

 

[Jim.ME]

This is the wire that burnt out, it goes to the relay on the top of the generator.

From the looks of the connection of the taped-up wire to the ammeter, I would replace the wire. That terminal end on the wire looks like it could have high resistance and be a fire risk.

Edited to correct wording.

 

[560Dennis]

lighting Resistor is open , they have them at YT Parts here under b electrical
I d change the field resistor also or get a new four position lighting switch.
by the time you pay part Cost and shipping, pays to buy new switch ,I’d say

 

[FarmallB1945]

Update, Yesterday I replaced almost all of the wires on the tractor looking for shorts and bad wires, after I finished that I started the tractor and it ran the same as before. After further inspection of the wiring schismatics in the Manuel I am thinking the wiring is messed up. On all but one of the diagrams show two wires coming off the generator to the ammeter and the other wire to the field switch, the diagram that only had one wire coming off the generator was a no battery system (I have a battery on my tractor). On my tractor the only wire coming off the generator goes to the ammeter. I will link a photo of the generator for you to see, (Disregard the green wire, that goes to the lights). If you could not tell by now I am not very well versed in the world of electricity so any input is helpful.

 

[FarmallB1945]

I also just noticed the generator also says 12v on it, it is kinda hard to see in the picture though

 

[BarnyardEngineering]

I also just noticed the generator also says 12v on it, it is kinda hard to see in the picture though

I can see the 12V. Does it have a 12V battery?

So the wire that burnt went to the "BAT" terminal on the relay on top of the generator? That "relay" is vour voltage regulator. It's an aftermarket regulator. I suspect the regulator failed causing the system to overcharge, burning your points and the wire. The burned points are why the tractor runs poorly.

You may be able to clean the points, or you may end up replacing the points and condenser in the distributor.

When you have it running again, connect a voltmeter directly to the battery and check the voltage. If it's charging higher than about 14V, it's overcharging.

 

[FarmallB1945]

The battery is a 6v

 

[used red MN]

Update, Yesterday I replaced almost all of the wires on the tractor looking for shorts and bad wires, after I finished that I started the tractor and it ran the same as before. After further inspection of the wiring schismatics in the Manuel I am thinking the wiring is messed up. On all but one of the diagrams show two wires coming off the generator to the ammeter and the other wire to the field switch, the diagram that only had one wire coming off the generator was a no battery system (I have a battery on my tractor). On my tractor the only wire coming off the generator goes to the ammeter. I will link a photo of the generator for you to see, (Disregard the green wire, that goes to the lights). If you could not tell by now I am not very well versed in the world of electricity so any input is helpful.View attachment 107422

I don’t think you are reading the wiring diagram correctly or it is the wrong one. You will only have one wire from the generator going to the ammeter. The other wire is from the field(F) terminal. Originally it went to the cut out or regulator. IH also had a system that the operator chose a high or lo charge by a selection on the dial light switch. Post w/ Farmall B hi lo charge diagram That linked post has a diagram of what I think your original wiring was, obviously your system has been modified. In my screen shot of your photo can you confirm that the wire circled is bolted under the bolt that is fastening that “cut-out” to the generator? If so that means the generator is always “full field”, grounding the field terminal on an “A circuit” generator system sets the generator to full charge output. I am not familiar with the operation of the Transpo D100 cut out you have. The little I read on it said it has an internal diode that inherently looses some voltage across it when current is flowing out of the generator into your battery. Having a diode that allows power to only flow one direction means when the engine/generator is stopped that power is not flowing out of your battery trying to turn the generator as if it is an electric motor. My guess is that as was said something failed in the cut out and the generator was drawing from the battery. The crimp connection was poor on the wire where it connected to the ammeter and it heated that section of the wire. How long have you had the tractor did it keep the battery up and show a charge on the ammeter during operation? The gap on the points looks okay from what I see. Run some 100 - 180 grit sandpaper through them each way to clean both contact sides. Then run a piece of cereal box type cardboard through them again both directions. If you have a feeler gauge reset them to .020” on the highest spot on the lobe (farthest open) Smearing a BB sized blob of grease around the cam lobes looks like a good idea they look dry.
How familiar are you with tractors and their operation? Do you think it has a steady misfire? You can check the individual cylinders for firing as follows. Pull the spark plug wires out of the cap and just poke them back in their terminals in the cap not totally seating them. Start the tractor and grab each wire about an inch back form the boot and pull it out. Just be aware there will be sparks jumping. As each wire is pulled away from the spark terminal there should be a change in the engine sound as that cylinder misfires. If you pull one out and there is no change that cylinder is misfiring. If you find one is not firing pull the spark plug and look to see if it is fouled.
Hopefully someone will chime in with more info on that Transpo cut out. If you actually have a 12 volt generator is charging full bore into a 6 volt battery that is far from ideal. The internals of the generator may have been changed, who knows. When you got the tractor did it have a 6 volt battery in it? This is getting very long, I am famous for this. There definitely needs to be more investigation done to your whole system to get it right.

 

[Jim Becker]

Update, Yesterday I replaced almost all of the wires on the tractor looking for shorts and bad wires, after I finished that I started the tractor and it ran the same as before.

No surprise there. Mucking with what is essentially a charging system problem won't fix an ignition problem.

Have you been using this tractor with this collection of electrical components or did you just buy this mess? I was going to stay out of this one, however:

You have a cut-out, not a voltage regulator. Your black wire from the generator F to ground forces the generator to full output at all times. This is not an unusual connection on early 6-volt systems but never done with 12-volts. If you really have a 12-volt generator hard wired to full output and use it to charge a 6-volt battery, you will either boil the electrolyte out of the battery or burn up the wiring (if the battery doesn't outright explode first). By the way, you have a Delco distributor. Common tune-up parts for an IH distributor will not fit.

I think you are in well over your head. I encourage you to find someone local that can look things over and figure out what you have and how it should be wired. There is only so much the online community can do based on pictures and limited descriptions.

 

[Jim Becker]

I see that used red MN commented while I was composing my previous post. Looks like we said a lot of the same things. I am sticking with my suggestion, get someone nearby to help.

 

[used red MN]

Update, Yesterday I replaced almost all of the wires on the tractor looking for shorts and bad wires, after I finished that I started the tractor and it ran the same as before. After further inspection of the wiring schismatics in the Manuel I am thinking the wiring is messed up. On all but one of the diagrams show two wires coming off the generator to the ammeter and the other wire to the field switch, the diagram that only had one wire coming off the generator was a no battery system (I have a battery on my tractor). On my tractor the only wire coming off the generator goes to the ammeter. I will link a photo of the generator for you to see, (Disregard the green wire, that goes to the lights). If you could not tell by now I am not very well versed in the world of electricity so any input is helpful.View attachment 107422

Looking closer and thinking about this more if the wire that melted is only going to the generator and your ammeter reads correctly as I shows a charge then the short jumper wire down to the switch should be placed on the right terminal with the wire from the generator. That blue wire on the left terminal should be going to the starter terminal with the battery cable on it. This is no real “revelation fix” in your wiring it will just allow discharge or subtraction of amperes to be shown from the draw of the ignition or headlights.