Alternator conversion not working

super99 · Apr 3, 2023

I converted a Farmall H from 6 to 12 volt and added a 1 wire alternator. All together and running but Alternator isnt charging. Im not sure if turns fast enough to get it to start charging, I went full throttle and it didnt start charging. The belt is too wide for the pulley on the alternator and rides half the belt width above the pulley. Im going to try a narrower width belt that rides lower to see if that speeds it up enough to get it to charge. There is a ground bolt on the alternator, I made a wire for it and hooked it to the motor but its rusty. Not sure its getting a good ground , maybe thats why its not charging?

Jim.ME · Apr 3, 2023

(quoted from post at 19:41:15 04/03/23) I converted a Farmall H from 6 to 12 volt and added a 1 wire alternator. All together and running but Alternator isnt charging. Im not sure if turns fast enough to get it to start charging, I went full throttle and it didnt start charging. The belt is too wide for the pulley on the alternator and rides half the belt width above the pulley. Im going to try a narrower width belt that rides lower to see if that speeds it up enough to get it to charge. There is a ground bolt on the alternator, I made a wire for it and hooked it to the motor but its rusty. Not sure its getting a good ground , maybe thats why its not charging?
<img src=https://www.yesterdaystractors.com/cvphotos/cvphoto151566.jpg>

<img src=https://www.yesterdaystractors.com/cvphotos/cvphoto151567.jpg>

You do not need a narrower belt, that will lead to slipping on the crank and water pump. You need a pulley the right width for the belt, but with a smaller diameter, they are available and should have been part of the conversion. If the generator was a Delco, the pulley should fit on the alternator.

This post was edited by Jim.ME on 04/05/2023 at 04:25 am.

Jim.ME · Apr 3, 2023

Where did you run the wire to the alternator battery terminal to? Did you remove the old voltage regulator, or at least disconnect the wires to it? Did you confirm the no charge by checking voltage at the battery, with a voltmeter, while running?

rustred · Apr 3, 2023

i have never hooked up a one wire, is there power at the alt output terminal with awitch on.? that looks too simple.

Jim.ME · Apr 3, 2023

(quoted from post at 19:55:03 04/03/23) i have never hooked up a one wire, is there power at the alt output terminal with awitch on.? that looks too simple.

Like any alternator the output (battery) terminal of a one wire alternator should not be through the switch.

rustred · Apr 3, 2023

and them ready rod threads are going to chew up that alternator mount. unless u have the bottom bracket squeezed tight.

M-MAN · Apr 3, 2023

It's grounded through the bracket bolts. The wire is unnecessary.

If it was me I would pull the black plug and make it a 3 wire. Speed won't matter then.

Jim.ME · Apr 3, 2023

It is worth a try, but not all one wire alternator are wired or have the right regulator for that to work.

rustred · Apr 3, 2023

thats what i was thinking.

rustred · Apr 3, 2023

you need a power supply to the alternator is what i am asking. i didnt think u could plunk that alternator on there and have it charging with
no power to it. that fat output wire should be running to the amp meter. just asking cause want to know this setup.

Geo-TH,In · Apr 3, 2023

Run the ground wire back to the negative of the battery and see if the alternator charges. If the alternator isn't charging,
connect the + of the alternator to + of battery. This will eliminate any wiring issues. Use a voltmeter to see if the voltage increases. If you have a clamp on DC ammeter use it to see if the alternator is charging.
-

Both my 3 wire delcos I have to rev the engine before they will charge. After the alternator kicks in, it will charge at lower RPMs

Auto store will check the new alternator.
Take it with you when you buy a new belt..

I recently bought this meter from Amazon for under $40.
I'm impressed with its ability to measure DC amps.

super99 · Apr 3, 2023

I got the wiring diagram from this site. I switched wires on the ammeter so polarity was correct, ran a #10 wire from ammeter to the alternator and put a 30 amp fuse in the line.

Dan67 · Apr 3, 2023

When i did mine i took the Alt. to a electrical repair shop and had them put in a low rpm exciter, worked great don't know if there still available.

leroy in ne · Apr 3, 2023

Jim.ME by memory fan/water pump driven by crank pulley with wide belt, generator/alternator conversion driven from fan pulley by smaller belt

Jim in NC · Apr 3, 2023

Make sure your fan belt is tight enough to prevent slippage. I have seen that a slightly loose fan belt can prevent alternators from charging at low engine speeds on several Farmall tractors.

Jim.ME · Apr 3, 2023

I am guessing he used the original generator belt. Parts Book looks like 3/4" belt on the fan and 1/2" for the generator. If that is the set up, 1/2" is too wide for the 3/8" pulley common on Delco alternators.

rustred · Apr 3, 2023

Very true. U should not be able to turn the alt fan with fingers when it is tight enough. Rule of thumb.

Jim.ME · Apr 3, 2023

Do you have battery voltage at the output terminal of the alternator? If not, check that the fuse hasn't blown. The alternator could have spiked above 30 amps and blown it. Confirm the wire from the alternator is not on the terminal with the wire to the solenoid, that would bypass the ammeter so charge wouldn't show.

Sam Womer (PA) · Apr 3, 2023

I had a Delco alternator converted to 6V, one wire. Put a 2 inch pulley on it, mounted it and ran the wire through an ammeter directly to the battery. It always charged even at idle after initial speed up. I think the smaller pulley is needed to spin the alternator fast enough. HTH Sam Womer(PA) This was on my John Deere LA..

Geo-TH,In · Apr 4, 2023

I know a guy who bought an 8N and they used a 1/2 belt. The belt slips and talks.
Stick with the 5/8 belt.

Alternator conversion not working

Well-known Member

Well-known Member

Well-known Member

Well-known Member

Well-known Member

Well-known Member

Well-known Member

Well-known Member

Well-known Member

Well-known Member

Well-known Member

Well-known Member

Member

Well-known Member

Well-known Member

Well-known Member

Well-known Member

Well-known Member

Member

Well-known Member

Similar threads