generator alternator conversion

[76cobraII]

I've got a 64 Galaxie 500 with a 289. Right now it's completely stock, but I'd like to change out my generator for an alternator. From what I've heard it's not too hard to do, but I don't know anyone who's actually done it.

Has anyone here made the changeover, and how did you do it?

[MagicRat]

Getting the right alternator makes a difference. Many older Ford alternators have 4 wires and an external regulator. Their wiring varies depending on whether you have a dashboard warning light or an ammeter, so installation can be complicated.

The best alternator to use is a GM "10SI" unit. This was used from about 1970 into the mid-80's. It is compact and comes in versions from 37 amp all the way to the rare 95 amp version, and has an internal voltage regulator!

Generally the 78 amp version is the strongest commonly available model.

Now, all factory versions (like the kind on your Camaro) have 3 wires coming out the back You can use this but you need a 10 amp resistor (I got mine from Radio Shack) and a simple wiring diagram.

The EASIEST way is to get one that has been converted to a "one wire" model where the 3 wires out the back have been replaced with just one. This wire simply hooks up to the battery's positive terminal, using 10 gauge or thicker wire.

These alternators are available on-line or through a boat parts dealer, that sells OMC or Mercury inboard parts. Some construction and farm equipment use the same alternators (Case/International come to mind).

The actual installation will likely require a bit of fabrication. I used a piece of 1/2 inch threaded rod, with nuts and washers to adapt it to the old generator bracket. You may have to shim it and possibly fabricate a support arm to get it to fit properly.

More details: http://www.oldengine.org/unfaq/10si.htm
http://www.ecrater.com/product.php?pid=1926832

[76cobraII]

Thanks MajicRat. That was great!
I'm a pretty good shade tree mechanic, but I don't know jack about wiring.
That helped a lot.
I'll keep you posted when I get it done. Thanks.