Wiring harness

scolley · May 10, 2014

[b:906793ad66]Howdy,

As some of you guys (and gals?) know, I'm trying to fix up a little tractor I just bought to work my hobby farm. Right now I'm trying to figure out what I need for a new wiring harness for my Ford 1948 8N tractor (SN *8N53458*) and where I may be able to source one. My little tractor has a front distributor and it has been converted to 12V. The problem I'm having is with the alternator. I don’t even know if it is one or three-wire or if it needs the extra diode. I think it has an internal regulator. It is a Duralast DL7127M and I have attached snapshots of it for your examination. [size=18:906793ad66][/size:906793ad66][/b:906793ad66]

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Jim WI · May 10, 2014

The way it is wired makes it a three-wire (the standard Delco 10SI). Heavy wire from the stud goes to the battery. One of the smaller wires (#1 terminal) is where the diode, lamp, resistor or switch is (source of power to start the alternator when the engine is running). The other smaller wire (#2 terminal) also goes to the battery (senses the battery voltage). The terminal numbers are generally marked on the body of the alternator.

scolley · May 10, 2014

Thanks Jim,

Since this one is a three-wire, would I need a the diode with this one if it is wired as a three?

Hobo,NC · May 10, 2014

I use a new 6V harness for your tractor and covet it to use with a alternator... Its a Wham Bamm thank you mam deal

scolley · May 10, 2014

(quoted from post at 13:13:30 05/10/14) I use a new 6V harness for your tractor and covet it to use with a alternator... Its a Wham Bamm thank you mam deal

Sounds good. How is that done?

souNdguy · May 10, 2014

diode, 194 lamp or similar.. correct resistor value, seperate tickle switch.. etc.. etc..

scolley · May 10, 2014

(quoted from post at 15:09:17 05/10/14) diode, 194 lamp or similar.. correct resistor value, seperate tickle switch.. etc.. etc..

Thanks Soundguy, I'm a chemist and new to mechanics so I guess I'll have to poke around for the specifics.

souNdguy · May 10, 2014

what specifically would you like to know?

#1 is the exciter wire. it runs fromt he switched side of the key to the #1 terminal. as isolation for the ignition you insert a 194 lamp or a diode.

if a diode.. use something like a 1n5408 or any diode generically capable of 1a50piv, or better yet.. 3a/200piv. the diode will have a marked side. that is the cathode. put the cathode towards the alt.

automagic with diode.

if you use the lamp method.. it functions like an idiot lamp. key on, engine off.. lamp on.. engine started and over 400 rpm, alt turns on.. lamp goes off....

your choice.

scolley · May 10, 2014

Thanks again. I think I need the light

souNdguy · May 10, 2014

all joking aside.

the light serves a good purpose. if you are going along and the lamp starts to glow or comes on.. you know there is a charge issue ( and discharge )... even if a slight one. Something a voltmeter may not show well untillt he battery is quite flattened. but an ammeter would immediately reveal...

scolley · May 11, 2014

[b:3cd406aadd]I just received this reply from an electrical harness specialist:[/b:3cd406aadd]

[size=9:3cd406aadd][i:3cd406aadd]You have a 63 amp alternator from Auto Zone.

It may be a self exciting version, but there is conflicting information on the internet.

You could call Auto Zone and ask if it is a 1 wire alternator.

If you un-plug the 2 wire white connector, and then start the tractor, it will charge the battery if it is self exciting.

A 12 volt conversion will also require a 12 volt coil and an external ignition resistor.

Can you send photos of the instrument panel showing the gauge connections and any other electrical connections?

Pricing:

$89 original engine harness

$20 additional for 63 amp alternator (you will require)

$15 additional if it requires an excitation circuit (you may require if it NOT a 1 wire version)
[/size:3cd406aadd][/i:3cd406aadd]

[b:3cd406aadd]I'm thinking now that it may be simpler and I can be more certain of the outcome if I just buy a 12 Volt conversion kit and replace what I have. What do you all think? If I do this, should I choose the one-wire or the three-wire alternator? I really like SouNdguy's suggestion of placing a lamp instead of a diode inline with one of the wires however I think that will require a 3-wire alternator.[/b:3cd406aadd][size=18:3cd406aadd][/size:3cd406aadd]

JMOR · May 11, 2014

(quoted from post at 08:45:59 05/11/14) [b:91417fa79b]I just received this reply from an electrical harness specialist:[/b:91417fa79b]

[size=9:91417fa79b][i:91417fa79b]You have a 63 amp alternator from Auto Zone.

It may be a self exciting version, but there is conflicting information on the internet.

You could call Auto Zone and ask if it is a 1 wire alternator.

If you un-plug the 2 wire white connector, and then start the tractor, it will charge the battery if it is self exciting.

A 12 volt conversion will also require a 12 volt coil and an external ignition resistor.

Can you send photos of the instrument panel showing the gauge connections and any other electrical connections?

Pricing:

$89 original engine harness

$20 additional for 63 amp alternator (you will require)

$15 additional if it requires an excitation circuit (you may require if it NOT a 1 wire version)
[/size:91417fa79b][/i:91417fa79b]

[b:91417fa79b]I'm thinking now that it may be simpler and I can be more certain of the outcome if I just buy a 12 Volt conversion kit and replace what I have. What do you all think? If I do this, should I choose the one-wire or the three-wire alternator? I really like SouNdguy's suggestion of placing a lamp instead of a diode inline with one of the wires however I think that will require a 3-wire alternator.[/b:91417fa79b][size=18:91417fa79b][/size:91417fa79b]

ounds like you are in the mood to waste money to me. Got a working alternator & want to replace it? Not with a generic re-built, no less, but with a 2X the cost "kit" alternator? Kit instructions will leave you at a loss! Your mount looks good & the kit brackets work, but look like a kid's erector set! Soundguy & Hobo are steering you in right directions

Hobo,NC · May 11, 2014

Looks like the harness business pays better than stealing...

BTW your harness touched the manifold that's not not good...

You can test the alternator right were it sets and test the harness you have also for proper operation and spend no money... Are you can take it off and have it tested free but you learn nuttin... The mounting of the alt you have looks home brew that may be good and may be bad its hard to say with out seeing more of it...

Anyhow a harness for a 48 to 50 1/2 8N use to be $20 bucks are so... Its no problem to convert to a 12V alt one wire are 3 wire.... Your call... Either way you go you will need a voltmeter I hang one on the tractor right were the OEM ammeter went and put the ammeter on the shelf... A voltmeter will answer most all issues you would have cranking, starting and operating your tractor... What you hang in that hole is not the issue now other than you are looking for a harness and your harness has shorted to the manifold one time are the other all you may need to do is repair the harness and check the alt out...

Jim WI · May 11, 2014

(quoted from post at 07:45:59 05/11/14)
[b:09377beb6a]I just received this reply from an electrical harness specialist:[/b:09377beb6a]

[size=9:09377beb6a][i:09377beb6a]Pricing:

$89 original engine harness

$20 additional for 63 amp alternator (you will require)

$15 additional if it requires an excitation circuit (you may require if it NOT a 1 wire version)
[/size:09377beb6a][/i:09377beb6a]

Seems more than a bit expensive to me. YT sells a wiring harness for your tractor for $39.95 -- http://www.yesterdaystractors.com/Ford-8N_Wiring-Harness-12-Volt_8NE10301.html

(quoted from post at 07:45:59 05/11/14) [b:09377beb6a]I'm thinking now that it may be simpler and I can be more certain of the outcome if I just buy a 12 Volt conversion kit and replace what I have. What do you all think? If I do this, should I choose the one-wire or the three-wire alternator? I really like SouNdguy's suggestion of placing a lamp instead of a diode inline with one of the wires however I think that will require a 3-wire alternator.[/b:09377beb6a][size=18:09377beb6a][/size:09377beb6a]

I would not. You've all the parts you need already. Folks here can help you figure out any problems you may have and then you can buy just the parts you need, if any.

Jim WI · May 11, 2014

(quoted from post at 11:41:00 05/10/14) Thanks Jim,

Since this one is a three-wire, would I need a the diode with this one if it is wired as a three?

If it is a three-wire, you need something to prevent the alternator from providing power to the coil through the wire on terminal 1 when you try to shut off the tractor. A diode is one way to do this. A lamp (like the idiot light in a car) is another.

Wiring harness

scolley

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Jim WI

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scolley

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Hobo,NC

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scolley

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souNdguy

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scolley

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souNdguy

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scolley

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souNdguy

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scolley

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JMOR

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Hobo,NC

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Jim WI

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Jim WI

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