electrical short in 1952 8N wireing system

My wires become hot, overheat, and the insulation melts on the #8 wires together from the rear of the alternator and from the solenoid that connect to each side of the ammeter. I have had to disconnect the battery cable (-).

I have replaced the alternator and ignition lock.

When I connected the battery, before i charged it, i could crank the engine over with or with out the key turned on, but could not start it.

After charging the battery, the wire become to hot too quick to see if it would crank over.

I have tried to follow the diagram in the original manual as well as a I & T shop manual, and it seems to be connected properly.

I now have a new ignition switch, ammeter and alternator.

Does anyone know why this would happen? This occurred in the fall. I had started the tractor, put started to lift the mower deck and then it died. I tried to start it again and that is when the ammeter started smoking and found out later that the wires had melted together. They were wrapped together with the white wire from the distributor, alternator, starter solenoid and starter.

What am i missing?

Would i need to check the starter, solenoid or starter switch and if so how for each?

Any help would be appreciated.

A good way to look for a short is to unhook one battery cable and to put a headlight in between the cable and the battery. It will be full bright while the short still exists, but will go out when the short is unshorted. In the meantime, you are not melting things down.

What terminal of the battery are you connecting to the frame of the tractor, ground? Tractor was originally positive ground BUT when you installing a alternator, you need the NEGATIVE terminal of the battery connected to the frame. My Father-in-Law connected the battery backwards in his 1965 Chevy truck with a alternator and melted the same wires you are speaking of. Check battery polarity.

Kent

Paul J, Thanks for you quick response. I am not sure what you mean by putting a headlight in between the cable and battery. The headlights are not hooked up. I did not mention that the tractor was converted to a 12v system.

As you can tell i am a novice or whatever.

Kent, Yes I have it as a positive ground. I will try a negative ground in the morning. If this works i will let you know first thing in the morning.

I may have turned my battery around when i charged it last fall.

Thanks.

What he means is to connect a light between the postive terminal of the battery and the cable that is normally connected to the positive terminal. While there is a short that battery cable will be grounded so when you find the short and disconnect it, the cable will no longer be grounded, and the light will turn off.

Mr Kent, I did turn the battery around and i still was able to press the starter switch and turn over the engine without turning the key on. I do not think this should happen. Any other suggestions?

Farmer Boy, thanks! I now have the battery with a positive ground. Would I need to reverse the battery so that i would get a negative ground? Also do i need a 12v light or can i use a 120v light bulb?

NOT a big 8N expert BUT depending on how the starting system is designed, the starter may be able to be engaged to crank the engine without the ignition switch in the on position.

Kent

Bill........would it surprize you to learn that the starter motor will turn yer engine over WITHOUT the ignition switch ON???

Would it surprize you to learn you can start the engine without a starter motor??? as long as the ignition switch is ON??? It's called and armstrong starter (hand crank) You can also "tow-start".

Howsomevers; that does not address yer melted wiring harness. When you installed yer 12V-battery positive ground, you shorted-out yer internal 12V-alternator solid state diodes and let the smoke out thru the wires and melted the insulation. Alternators DEMAND negative ground. Take yer alternator into enny autoparts store for a "free" checkout. Simple, eh?

Unfortunately neither the Ford manuals ...nor... the I&T FO-4 manual show or describe a 12V-conversion. There are plenty of home-grown wiring diagrams for 12V-conversions. I like the 3-wire conversion that uses an "idiot-lite".

You definately need to change yer roundcan ignition coil to a real 12V-coil that uses NO resistors ever. Recommend the NAPA IC-14SB. ($15, cheap) ........Dell, a 12V advocate for the right reason

That is normal, but I think you have let the smoke out of the alternator by switching the ground around.

The way I understand positive ground is that it"s just opposite. Never worked with one so I don"t know for sure. If that is the way it works negative goes to the starter right? If so, just put the light inbetween the negative post and negative cable. But like the others said, positive ground and alternators don"t mix. You need a 12 volt light to do this. By the sounds of it though your problem is an alternator and positive ground

Dell,...Yes it would but i know nothing. I am not joking, so please do not be offended.

No, I just don't have the crank.

So the mistake I made was to use a positive ground in lieu of the negative ground from the battery since i have a 12V conversion with an alternator. Thus i then shorted out the internal 12V-alternator solid state diodes. #@#$$ I was afraid of that. Would have i shorted-out any other items such as the ignition switch, starter solenoid, starter or starter switch?

Just for your info i did look on line and found a free diagram from K LaRue that fit my tractor but it had the negative ground and of course i was right and not them. I will see what i can do about the 12V coil that uses no resisters. I would assume that the resister is the rectangular ceramic piece located on the right hand side above and behind that rpm gauge.

Thank you for your help.