charging system and ignition question.

[8n/9n]

I am going to instal an alternator, a 12 volt battery and a 12 volt coil soon, what I wantto know is wheather or not I can fins a resister without buying that kit with everything from this site becauseI want a 1 wire alternator. So What I want is a radio shack or napa part number for the resistor, or a description of the details on it so I can find one.
Also I am replacing all of my switches so I would like to know how many amps there are going through the switch that turns on the coil and how many amps there are going through the starter switch.
Thanks Ben.

 

[Bob]

No one can give you accurate advice on the resistor without knowing the actual primary resistance of the coil you get. There are several variations on the market nowadays, from the "land of almost right", I guess.



The bottom line is that you need enough resistance ahead of the coil to limit the primary current to not much over 3 Amps, and DEFINITELY not over 4 Amps. This is with the ignition switch "ON", the engine NOT running, and the breaker points CLOSED.

PLEASE reconsider getting a one-wire alternator. A standard 3-wire unit is really easy to connect up, and CHEAPER, and performs BETTER.

You just need a Delco 10SI alternator, and a diode or "idiot lamp" to connect it up. The diode or the lamp can be used interchangeably.

<img src = "http://ndtc3500.stellarnet.com/~blweltin/Bob/AlternatorHarness3.jpg">

The current draw through the ignition switch will be LESS than 5 Amps, UNLESS you power headlights through it.

Do you have an 8N chassis or a 9N chassis? The 9N starter switch carries the full current draw of the starter, somewhere between 100 and 200 Amps.

The 8N tranny-top mounted neutral safety starter switch carries only the current needed to activate the solenoid, less than 10 Amps.

Which ever tractor you have, I HOPE you'll retain the functionality of the neutral-safety starter switch!

 

[Anonymous-0]

Currently the nuetral saftey switch is completley dissconnected, it was through a pair of switches on the das pannel witch I 'accidentily' tore out last night. Thank you for all that help, I will just get the kit from the site rather than bothering with locating all the parts I need.

 

[Bob]

From some of the posts on here, it seems you cannot be SURE the coil and resistor in the kit will even match, due to the variations in parts nowadays.

If at all possible, it's still a good idea to measure the actual primary ignition current before starting and using the tractor, if at all possible.

With a functioning ammeter in the dash, you will see it delect to "discharge" when the ignition is switch on. This will give you some idea of the ignition current, NOT as accurate as Amp tester, though.

 

[Bruce (VA)]

You might find these two articles helpful.

http://www.n-news.com/specialads1.html


The first one gives reasons & excuses for converting to 12v & the second gives options for during it correctly. If you spend any time at all on this board, you will see that 75% of the ignition related problems are thanks to a poorly done or poorly understood 12v conversions.

 

[Anonymous-0]

Hey, 8n/9n.....pay attention to what Bob said about the resistors & 3-4 amps or you will be buying coils.
Experience speaks.

 

[souNdguy]

While you are at it.. why not hook that safety starter switch back up.. it may save your life one day..

Soundguy

 

[A. Bohemian]

Quote: ''If you spend any time at all on this board, you will see that 75% of the ignition related problems are thanks to a poorly done or poorly understood 12v conversions.''

Thou hast said the thing which should be said. Amen, verily, selah.

 

[Anonymous-0]

Bob-
I don"t have ammeter, so am I correct by measuring 1.7 ohm to top of 12V coil, plus (known) 2.5 ohm coil, giving a total R=4.2 in series to coil; so calculated primary Amps is 3A OFF (12.6V) and 3.5A ON (at 14.6 volts)? Do any of these resistances vary significantly when running?
Also, just curious, why are diode and lamp (resistor) interchangeable?

 

[Bruce (VA)]

Tnx, and I fear it will get worse as far as frontmount conversions go. Seems that the resistance values in the alleged '12v' coils are not consistent in some of the new coils.

 

[Anonymous-0]

My first rule is this.If a machine is working well,leave it alone.My 6v system is just fine so I wont mess with it.The 12v converters and their strange problems are good for a lot of laughs.Friends and I had a cutdown Model A when we were in our early teens.We knew more about fixing the Ford than present day 12 volt turkeys.We couldnt afford the conversion parts any way.

 

[Anonymous-0]

See, it is not running fine, not running at all. I am completely re wiring the whole tractor, new starter will need a batery and many other things so I think that doing a conversion, the right way, is what I should do.