The Ford Barn

rotorwrench · 06-24-2025, 06:55 PM

Normally the Delco 10si alternator is a 3-wire 12-volt unit but years ago someone developed the 6-volt conversion. They changed the internal voltage/current control unit and added a jumper to swap polarity. These are strictly a one wire unit. One thing I've noticed about them is that output voltage is higher than what a 6-volt battery should receive. None of the ones I've checked put out 7.2-volts. It's more like 7.8 or more. Running with lights on all the time will help the battery.

There is a new voltage regulator out again that will control a stock model A generator. These set ups will at least charge the battery within normal parameters. The guy who sells them is into model T starters and has a web site.

06-24-2025, 06:55 PM	#7
rotorwrench Senior Member Join Date: Jun 2010 Location: San Antonio, Texas Posts: 17,410	Re: Alternators Normally the Delco 10si alternator is a 3-wire 12-volt unit but years ago someone developed the 6-volt conversion. They changed the internal voltage/current control unit and added a jumper to swap polarity. These are strictly a one wire unit. One thing I've noticed about them is that output voltage is higher than what a 6-volt battery should receive. None of the ones I've checked put out 7.2-volts. It's more like 7.8 or more. Running with lights on all the time will help the battery. There is a new voltage regulator out again that will control a stock model A generator. These set ups will at least charge the battery within normal parameters. The guy who sells them is into model T starters and has a web site.