Altenator wiring

T L

Member
I just purchased a 8N with a delco alternator on it. There is only 1 wire coming out of it. The side where there is usually a plug with 2 wires is blocked off with a rubber plug. The one wire goes to the amp gauge and the other side of the amp gauge goes to the battery. It charges great but there is a draw on the battery. Does anyone have an idea what I need to do?
 
(quoted from post at 20:56:17 03/05/18) I just purchased a 8N with a delco alternator on it. There is only 1 wire coming out of it. The side where there is usually a plug with 2 wires is blocked off with a rubber plug. The one wire goes to the amp gauge and the other side of the amp gauge goes to the battery. It charges great but there is a draw on the battery. Does anyone have an idea what I need to do?
ow much draw? A few hundred micro-amperes is normal.
 

I just went through the wiring on one of my Case tractors. The two wires from the alternator plug were used on this application. The number one wire looped over to the battery lug, and the number two wire went to the ignition switch. The one marked Battery could go to the hot side of starter solenoid, or to the positive pole on the ignition switch. How is it that a Ford tractor only uses the battery post on a GM alternator?
 
(quoted from post at 07:37:38 03/06/18)
I just went through the wiring on one of my Case tractors. The two wires from the alternator plug were used on this application. The number one wire looped over to the battery lug, and the number two wire went to the ignition switch. The one marked Battery could go to the hot side of starter solenoid, or to the positive pole on the ignition switch. How is it that a Ford tractor only uses the battery post on a GM alternator?

L.Fure, the OP obviously has an aftermarket bastardization of a Delco alternator sold as a "one wire alternator".

They have been known to slowly drain the battery when sitting unused, some were worse than others, or the alternator may simply be internally defective.
 
(quoted from post at 08:37:38 03/06/18)
I just went through the wiring on one of my Case tractors. The two wires from the alternator plug were used on this application. The number one wire looped over to the battery lug, and the number two wire went to the ignition switch. The one marked Battery could go to the hot side of starter solenoid, or to the positive pole on the ignition switch. How is it that a Ford tractor only uses the battery post on a GM alternator?
he way L.Fure has #1 & 2 reversed, your drain should be above normal.
 
(quoted from post at 13:53:27 03/06/18)
(quoted from post at 07:37:38 03/06/18)
I just went through the wiring on one of my Case tractors. The two wires from the alternator plug were used on this application. The number one wire looped over to the battery lug, and the number two wire went to the ignition switch. The one marked Battery could go to the hot side of starter solenoid, or to the positive pole on the ignition switch. How is it that a Ford tractor only uses the battery post on a GM alternator?

L.Fure, the OP obviously has an aftermarket bastardization of a Delco alternator sold as a "one wire alternator".

They have been known to slowly drain the battery when sitting unused, some were worse than others, or the alternator may simply be internally defective.

There is a diode in one wire to stop the battery drain.
 
(quoted from post at 10:13:45 03/06/18)
(quoted from post at 13:53:27 03/06/18)
(quoted from post at 07:37:38 03/06/18)
I just went through the wiring on one of my Case tractors. The two wires from the alternator plug were used on this application. The number one wire looped over to the battery lug, and the number two wire went to the ignition switch. The one marked Battery could go to the hot side of starter solenoid, or to the positive pole on the ignition switch. How is it that a Ford tractor only uses the battery post on a GM alternator?

L.Fure, the OP obviously has an aftermarket bastardization of a Delco alternator sold as a "one wire alternator".

They have been known to slowly drain the battery when sitting unused, some were worse than others, or the alternator may simply be internally defective.

There is a diode in one wire to stop the battery drain.
topping battery drain is not the purpose of the diode. Wrong direction for that.
 
(quoted from post at 14:09:08 03/06/18)
(quoted from post at 08:37:38 03/06/18)
I just went through the wiring on one of my Case tractors. The two wires from the alternator plug were used on this application. The number one wire looped over to the battery lug, and the number two wire went to the ignition switch. The one marked Battery could go to the hot side of starter solenoid, or to the positive pole on the ignition switch. How is it that a Ford tractor only uses the battery post on a GM alternator?
he way L.Fure has #1 & 2 reversed, your drain should be above normal.

I didn't describe this accurately. #2 wire goes to battery post on the alternator, and #2 to the ignition switch. Sorry about that.
 
(quoted from post at 10:21:30 03/06/18)
(quoted from post at 14:09:08 03/06/18)
(quoted from post at 08:37:38 03/06/18)
I just went through the wiring on one of my Case tractors. The two wires from the alternator plug were used on this application. The number one wire looped over to the battery lug, and the number two wire went to the ignition switch. The one marked Battery could go to the hot side of starter solenoid, or to the positive pole on the ignition switch. How is it that a Ford tractor only uses the battery post on a GM alternator?
he way L.Fure has #1 & 2 reversed, your drain should be above normal.

I didn't describe this accurately. #2 wire goes to battery post on the alternator, and #2 to the ignition switch. Sorry about that.
ou are getting closer, but that is OK, I know how it goes. :)
 

Anything electrical is a real road block for me. I must have done something right with my tractor. The alternator charges the battery and it doesn't discharge the battery while sitting in the barn.
 
(quoted from post at 11:11:08 03/06/18)
Anything electrical is a real road block for me. I must have done something right with my tractor. The alternator charges the battery and it doesn't discharge the battery while sitting in the barn.
ell, just leave it be & KEEP ON TRUCKIN'. :)
 
(quoted from post at 16:17:27 03/06/18)
(quoted from post at 11:11:08 03/06/18)
Anything electrical is a real road block for me. I must have done something right with my tractor. The alternator charges the battery and it doesn't discharge the battery while sitting in the barn.
ell, just leave it be & KEEP ON TRUCKIN'. :)

I thought I finally had a handle on how this works, but ended up muddying the water again.
 
(quoted from post at 11:29:54 03/06/18)
(quoted from post at 16:17:27 03/06/18)
(quoted from post at 11:11:08 03/06/18)
Anything electrical is a real road block for me. I must have done something right with my tractor. The alternator charges the battery and it doesn't discharge the battery while sitting in the barn.
ell, just leave it be & KEEP ON TRUCKIN'. :)
ot to worry.

I thought I finally had a handle on how this works, but ended up muddying the water again.
 

for the youngins who might not understand... ;)

KOT-2510001.jpg
 
How serious a draw? How long does it have to set before affecting it starting the next time out.?

As Bob said, this is not an uncommon problem with some one wire or self exciting alternators. A parts store alternator test may not show the problem.

I see 3 possible solutions:
1. Disconnect negative ground cable when not in use
2. Install a disconnect switch in the ground cable
3. Replace the alternator.
 
(quoted from post at 15:29:51 03/06/18) How serious a draw? How long does it have to set before affecting it starting the next time out.?

As Bob said, this is not an uncommon problem with some one wire or self exciting alternators. A parts store alternator test may not show the problem.

I see 3 possible solutions:
1. Disconnect negative ground cable when not in use
2. Install a disconnect switch in the ground cable
3. Replace the alternator.

Well, a 4th option may be to do nothing, as even the factory 10SI on a GM vehicle has a constant drain on battery & he never quantified the drain. Factory set up would theoretically take about a year to totally drain the battery, so it ought to go months before a no start.
 

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Back
Top