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100-4 generator to alternator conversion?

bj8bn2

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Has anyone converted a 100-4 from generator to alternator? I'm looking for detailed "how-to" information. Thanks.

August

1956 100-4
1967 3000
 
I have not personally done it on the 100-4, but it should very straight forward. I would use a GM one wire type. First, is your car neg ground? You'll need to fab up some brackets. If you don't have the tools to weld and drill I have an engine here under the bench. I could make brackets for you. Wiring will require a lead from the alternator to the + battery terminal and a switched exciter wire with a bulb in line like the generator wire is now.
 
There is an article for the generator-to-alternator changeover on the NTAHC web site (www.ntahc.org). It is article number 8 under "Tech Tips".

Here's a link to it = https://tinyurl.com/5ajap2

I just wrote Don to see if he has a like article for the 100-4. I'll let you know.

Tim
 
August--

The wiring part of the conversion is quite straightforward as others say. The only special challenge a 100 presents is whether you can find an alternator with a pulley that will accept the wider fan belt.

I use a Prestolite/Leece-Neville 75 amp alternator that came with a "Universal" two-piece shiv that can be shimmed out with washers to take the wide belt. I have had this alternator on my 100 for about eight years after briefly trying a Lucas alternator that I got from "The Cape" along with a mounting bracket that bolts onto the block in place of the original bracket. The diode holder in the Lucas unit melted within a few hours of installation--However the Cape bracket was nicely made out of cast aluminum and I used that from which to hang the Prestolite.

A nice feature of the Prestolite is that the regulator is externally mounted and if it goes off you don't have to change out the entire unit.

Let me know if you need pictures.
 
Thanks Michael and everyone for your response. I went to e-bay looking for the recommended Delco alternator and I found a seller that specializes in generator to alternator conversions. This is the link https://stores.ebay.com/Kansas-Select-Products I can get a 63 amp alternator and bracket, a wider puller and the wiring harness for about $100 plus shipping. The bracket is not great looking but it will do for now. I'm going to give this a try. I'll submit a post when I get it done (and it's working!).

Again, thanks for the advise.

August
 
August -

Hey, that's a great little website with some good stuff in it. Let me know how it installs, and if that little bracket doohickey is any good. I've been looking for a good way to install an AC & gen set to my A90 Atlantic.
 
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