The Ford Barn

markdtn · 05-13-2025, 08:20 AM

I have an 8BA in a 2N Ford tractor. It has a 63A 10si Delco alternator (high amps needed for a Taurus electric fan-no room for a mechanical fan). I'm in the process of putting the engine in an 8N tractor so while it is exposed and I have to rewire it anyway I thought about using a Ford 3G alternator instead of the Delco to be all Ford. I see that the mounting holes on a small case 3G are closer to 7" spacing instead of 6 5/8" but other than that I don't see why I couldn't do it. Anybody else put a Ford 3G (or 4G) alternator on a flathead instead of the Delco 10/12si? I know I could probably put an earlier Ford alternator but I like the internal regulator to keep things clean looking. I would wire it with a charge light and a voltmeter.

cas3 · 05-13-2025, 09:32 AM

I always loved those tractors with a v8! I don't think most folks could tell what kind of alternator is on there, I'd just do whats easiest

markdtn · 05-13-2025, 09:58 AM

No, you are correct, it's hard to tell what alternator is on there with the hood on. The 10si 1-wire Delco conversions are very commonplace on a lot of cars, tractors, and equipment. Because they are easy, available, and cheap. And I will say this, I am a hard core GM guy, but it has always bothered me a little that I had a GM alternator on a Ford. I don't know why, it just does. It has a Taurus fan, so that is Ford. It has a Volvo 2-speed fan relay so you can stretch and that was Ford. It has a BMW fan switch/sending unit that really fits the bill for 2-speed electric fan control. There is nothing out there like it for that switch so I squint and ignore that. But the alternator could be Ford I think. I have found that '91-96 Escorts used a small case 3G style alternator that is 75A output. I may try to find one and try it. Best I can tell the center part of the alternator is 5mm larger radius-so like 3/16". I think the bracket will accommodate that. I would just have to slot the mounting holes and it should bolt up. I have a wide belt pulley for the Delco that I THINK will bolt onto a 3G. If not, those are out there. I know this is not traditional Flathead stuff, but I thought maybe there was a die-hard Ford guy (or gal) out there that needed an alternator for their application and would not have GM stuff on their Ford. Either way I am wiring it 3 wire this time because I don't like to have to rev it cold to make it start charging. Thanks!

Gene1949 · 05-15-2025, 05:08 PM

Quote:

Originally Posted by markdtn

It has a Taurus fan, so that is Ford. It has a Volvo 2-speed fan relay

Pretty much my setup. Bought aftermarket thermal switches and mounted the in the bottom tank next to the outlets. Thermostats regulate engine temp and there is no sense running the fan if the radiator is managing the heat load.
Used a '97 SVO alternator (130 amp I think). I also wanted to use the sensing wire, just like Ford intended. IF it was cheaper to run a single wire setup Ford would have done it. I also ran the smallest diameter pully I could find. Given the low RPMs our motors are used, made sense to spin it faster at low speed.

Flathead Fever · 05-15-2025, 05:42 PM

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I have three of those 8N tractors One I rebuilt the engine 40 years ago and the engine and generator are still going strong. I had the one and then I bought two more dirt cheap, not running. The engines run something else in the transmission broke/ I paid $500.00 for each of them. Nice sheet metal on them. I'd thought I'd do something with them but then I had stroke. Both of those have alternators on them. I finally bought a Kubota with a bucket and now the 8Ns are yard art. The 8N's are great tractors for discing but the ground is so hard here and so full of big rocks I had to upgrade to the Kubota.

05-13-2025, 08:20 AM	#1
markdtn Senior Member Join Date: Jun 2016 Location: Chattanooga, TN Posts: 164	Flathead alternator conversion-Ford alternator? I have an 8BA in a 2N Ford tractor. It has a 63A 10si Delco alternator (high amps needed for a Taurus electric fan-no room for a mechanical fan). I'm in the process of putting the engine in an 8N tractor so while it is exposed and I have to rewire it anyway I thought about using a Ford 3G alternator instead of the Delco to be all Ford. I see that the mounting holes on a small case 3G are closer to 7" spacing instead of 6 5/8" but other than that I don't see why I couldn't do it. Anybody else put a Ford 3G (or 4G) alternator on a flathead instead of the Delco 10/12si? I know I could probably put an earlier Ford alternator but I like the internal regulator to keep things clean looking. I would wire it with a charge light and a voltmeter.

05-13-2025, 09:32 AM	#2
cas3 Senior Member Join Date: Jan 2011 Location: Beverly Kansas Posts: 5,301	Re: Flathead alternator conversion-Ford alternator? I always loved those tractors with a v8! I don't think most folks could tell what kind of alternator is on there, I'd just do whats easiest

05-13-2025, 09:58 AM	#3
markdtn Senior Member Join Date: Jun 2016 Location: Chattanooga, TN Posts: 164	Re: Flathead alternator conversion-Ford alternator? No, you are correct, it's hard to tell what alternator is on there with the hood on. The 10si 1-wire Delco conversions are very commonplace on a lot of cars, tractors, and equipment. Because they are easy, available, and cheap. And I will say this, I am a hard core GM guy, but it has always bothered me a little that I had a GM alternator on a Ford. I don't know why, it just does. It has a Taurus fan, so that is Ford. It has a Volvo 2-speed fan relay so you can stretch and that was Ford. It has a BMW fan switch/sending unit that really fits the bill for 2-speed electric fan control. There is nothing out there like it for that switch so I squint and ignore that. But the alternator could be Ford I think. I have found that '91-96 Escorts used a small case 3G style alternator that is 75A output. I may try to find one and try it. Best I can tell the center part of the alternator is 5mm larger radius-so like 3/16". I think the bracket will accommodate that. I would just have to slot the mounting holes and it should bolt up. I have a wide belt pulley for the Delco that I THINK will bolt onto a 3G. If not, those are out there. I know this is not traditional Flathead stuff, but I thought maybe there was a die-hard Ford guy (or gal) out there that needed an alternator for their application and would not have GM stuff on their Ford. Either way I am wiring it 3 wire this time because I don't like to have to rev it cold to make it start charging. Thanks!

05-15-2025, 05:42 PM	#5
Flathead Fever Senior Member Join Date: May 2010 Location: Yucaipa, CA Posts: 1,360	Re: Flathead alternator conversion-Ford alternator? Sponsored Links (Register now to hide all advertisements) I have three of those 8N tractors One I rebuilt the engine 40 years ago and the engine and generator are still going strong. I had the one and then I bought two more dirt cheap, not running. The engines run something else in the transmission broke/ I paid $500.00 for each of them. Nice sheet metal on them. I'd thought I'd do something with them but then I had stroke. Both of those have alternators on them. I finally bought a Kubota with a bucket and now the 8Ns are yard art. The 8N's are great tractors for discing but the ground is so hard here and so full of big rocks I had to upgrade to the Kubota.