12v Conversion

[Matthew87]

I recently picked up a 52 8N that someone started a 12v conversation on. Does anyone have a wiring diagram that could assist me in placing these wires. Everything I find on google or YouTube doesnt seem to work for mine.

 

[Bruce (VA)]

Google wiring diagrams JMOR
75 Tips

 

[Tim PloughNman Daley]

Newbie or Oldie, you really need to invest in the ESSENTIAL MANUALS. Know how everything works and then do your 12V switch over. FORD never used 12V until late 50's with introduction of the diesel models so you won't find any Ford diagrams there. As Bruce said, JMOR's WIRING PICTOGRAMS has every correct way to wire up these old Fords in both 6V and 12V systems. With a 12V using the side mount, if your coil is the OEM 6V unit, you need to add an in-line external 1-OHM resistor in the coil wire circuit. Omit it if you spring for a 12V coil. Whichever system, if the GEN or ALT do not use a belt tension bracket, you will never charge the battery. Of course all this hinges on a good brand, fully tested under load and charged battery AND a correctly tuned up distributor and wiring. Here's a page for the 8N 12V conversion. Don't skip steps. Leave gaggle and UTOOB for the socialists.

FORD TRACTOR w/SIDE MOUNT DIST, OEM 6V/POS GRN:

FORD 8N AFTER S/N 263843, WIRING PICTOGRAMS by JMOR:

FORD 8N TRACTOR ESSENTIAL OWNER/OPERATOR/PARTS/SERVICE MANUALS:

Tim Daley(MI)

 

[Tim PloughNman Daley]

Newbie or Oldie, you really need to invest in the ESSENTIAL MANUALS. Know how everything works and then do your 12V switch over. FORD never used 12V until late 50's with introduction of the diesel models so you won't find any Ford diagrams there. As Bruce said, JMOR's WIRING PICTOGRAMS has every correct way to wire up these old Fords in both 6V and 12V systems. With a 12V using the side mount, if your coil is the OEM 6V unit, you need to add an in-line external 1-OHM resistor in the coil wire circuit. Omit it if you spring for a 12V coil. Whichever system, if the GEN or ALT do not use a belt tension bracket, you will never charge the battery. Of course all this hinges on a good brand, fully tested under load and charged battery AND a correctly tuned up distributor and wiring. Here's a page for the 8N 12V conversion. Don't skip steps. Leave gaggle and UTOOB for the amateurs.

FORD TRACTOR w/SIDE MOUNT DIST, OEM 6V/POS GRN:

FORD 8N AFTER S/N 263843, WIRING PICTOGRAMS by JMOR:

FORD 8N TRACTOR ESSENTIAL OWNER/OPERATOR/PARTS/SERVICE MANUALS:

Tim Daley(MI)

 

[Ultradog MN]

The simplest diagram for a 3 wire 10SI conversion is below. It is not specific to Ns but is easy to follow.
One small change I always make is instead of running the #2 sense wire all the way back to the battery I just make a short jumper wire and connect it to the batt terminal on the back of the alternator.

 

[Duner Wi]

Ultradog MN
Here is what happens according to Delco Website if you hook alternator with remote sense capabilities like your wiring diagram show.

A major fleet reported to us that their Delco Remy Alternators equipped with Remote Sense reduced battery charge time by 50% and decreased battery warranty claims by 30%. Remote Sense utilizes a second wire that reads the actual voltage at the battery and signals the alternator to increase its voltage output to compensate for the voltage drop

 

[JerryLook]

(quoted from post at 14:02:25 07/31/21) Ultradog MN
Here is what happens according to Delco Website if you hook alternator with remote sense capabilities like your wiring diagram show.

A major fleet reported to us that their Delco Remy Alternators equipped with Remote Sense reduced battery charge time by 50% and decreased battery warranty claims by 30%. Remote Sense utilizes a second wire that reads the actual voltage at the battery and signals the alternator to increase its voltage output to compensate for the voltage drop

I just did a 10si conversion on my 3000, and jumpered the sensing wire to battery post on the alternator. Like Ultradog and many other people do. I ran a new 10 awg wire. The voltage drop for my 5 run is less than .2 VDC. If I had run the original (what looked like 16 awg wire) the drop would have been higher, around .8 VDC. Assuming also a 5 run.
Im ok with the .2 but maybe not the .8.

 

[JerryLook]

Supposed to read 5 foot run. Some times this site takes away my punctuation

 

[Ultradog MN]

Duner,
Thanks for that.
I am not an electrics guru and will not even try to dispute Delco.
I have done a several conversions but they were all on 3 cyl model tractors.
Like Jerry Look says above, there is about 5' of #10 wire between the alternator and the starter solenoid. There is also a 2 1/2' long 00 battery cable from the solenoid to the battery post. So 7 1/2' in all.
If you ran the sense wire via the shortest possible route directly from the #2 connector to the battery post it would probably require 4' of wire.
On an N conversion those distances would be shorter.
I would have to learn a heck of a lot more about electrics to understand how that extra length will make a difference. But for all I know it might.
Perhaps Jmor et al. can weigh in and explain this for us.

 

[Jim.ME]

(quoted from post at 09:30:19 08/01/21) Duner,
Thanks for that.
I am not an electrics guru and will not even try to dispute Delco.
I have done a several conversions but they were all on 3 cyl model tractors.
Like Jerry Look says above, there is about 5' of #10 wire between the alternator and the starter solenoid. There is also a 2 1/2' long 00 battery cable from the solenoid to the battery post. So 7 1/2' in all.
If you ran the sense wire via the shortest possible route directly from the #2 connector to the battery post it would probably require 4' of wire.
On an N conversion those distances would be shorter.
I would have to learn a heck of a lot more about electrics to understand how that extra length will make a difference. But for all I know it might.
Perhaps Jmor et al. can weigh in and explain this for us.

Perhaps a lower battery voltage due to loads on the battery, such as lights, might be seen as a greater difference than voltage at the alternator output terminal. But I doubt it is enough on a tractor, with no high loads like AC or heat, to matter. A semi, with heat/AC, maybe a fridge, and decked out with lights, could be a different story, so likely such units will be better served connected closer to the battery(s). Just my thoughts.

 

[Destroked 450]

Did this conversion on my 4000 21 years ago
Have do half dozen more since with no issues

 

[Ultradog MN]

John,
Hmmm...
We get to pick another guy's tractor apart.
I see some mix and match.
4000 with a late style block but old style
power steering - with new style pump. And,
a diesel with the crankcase vent tube off a
gasser. You can trust me not to tell anyone
tho - cause I like it. It would fit right
in here.
Oh, and your little jumper on the sense
wire works for me too.

 

[Duner Wi]

Ultradog Mn
Thank you for replying. I am no electrical expert but try to learn from people who should know more than me.
Forty plus years ago when I did my first 12 volt alternator conversion I had my 10 or 12 SI in hand, now I have to figure out how to wire it so I ask my friend and who has done a few and he says loop the remote sense wire on alt. to batt + on alt. I am thinking why would not GM do it this way so I looked at my Motors Manual and they run the R2 sense wire back closer to the battery. My explanation is
the battery is the storage and so alternators job is to keep the battery fully charged and supply enough charge for current needs. For alternator to work to its full capabilities it need good information and to do this it needs to read battery voltage nearer the battery about where the batteries cable first connection is, (usually near or at the starter) many times this connection is where the feed is for lights ignition etc.
My thinking is if you only need to run ignition and occasional lights the short looped remote sense wire works good enough, if you run lights, heat, air, radio etc and more, than the remote sense wire attached to where Delco says will be of benefit.