The Stovebolt Site Forums The Shop Area The Electrical Bay 12v generator shaft size?

Hi,

This isn't really about a stovebolt but I had great luck getting info from you guys when I was restoring my '53 Chevy I figured I might as well ask. My 1957 Divco has a 6v delco generator with a large 3/4" belt pulley on it. All the generator guys I have talked to have said it is unlikely they can get parts / convert it to 12v.

My new plan is to use a common 12v delco generator out of a late 50's Chevy truck. They are dime a dozen and the parts availability shouldn't be too bad. My only concern is whether my pulley will swap over. Does anyone know what the shaft size is on a late 50's delco generator? For that matter, are the shaft sizes reasonably standard or are they model dependent?

Any info would be great, for something I thought would be nice and simple this has become a real pain in the rear!

I believe the pulleys will swap, but to be sure, give these guys a call. They specialize in rebuilding obsolete/oddball electrical stuff from Model T days up to present time stuff.


Todd's Auto Parts Incorporated
206 N 1st St, Nashville, TN 37213
(615) 254-6264

Jerry

I did this same thing successfully in 2012. I ordered a 12V generator (55 2nd or later) from one of the parts houses and swapped the pulley from my 6V generator over.

I called first to make sure that they would accept a 6V as a core for a 12V. They agreed as long housing length was the same.

The only issue was getting the pulley off of the old 6V unit, I needed an impact to get the bolt loose and used a gear puller to get the pulley free.

Have fun.

All standard size Delco automotive generators from the 30s up to the 60s in 6v or 12v used the same shaft size. .650. The exception to that would be a larger oversized generator. The larger units had a larger shaft size but cant remember it off the top of my head. If you need that info I can measure one tomorrow for you. I can look it up and see if the Delco book tells me what your Divco had on it originally and get back with you.
Ken

Hi Ken,

If you could measure one of your over sized generators that would be great. I get the feeling my generator has the larger shaft size.

If you could look in a delco book that would also be great. The number stamped on my current generator is 1105876. Whether that is original to my truck I have no idea.

Thanks

I can tell you right off the bat that the 1105 series is the larger generator and larger shaft size. Converting that generator can be done but very expensive to do. You would be better off going with a later model, in the mid 50s to early 60s, long case Delco generator and then finding a pulley off of a late 40s to early 50s GMC as they had a wide belt. If you need help with what your doing or cant find parts etc. send me a message and I can help you out with a complete set up or whatever you would need for it.
Regards,
Ken

I believe the shaft is 17 mm. I say this because the pulley off my GMC 6 volt Generator fit a modern alternator shaft. The early 1950 GMC generator will have the wider 3/4 belt as stated above.

Did the GMCs also have a pulley made for 7/8" belts? There are some posts here that mention it but it seems like they are as rare as hens teeth.

Even then I would think the 7/8" pulleys would use the larger generator like I already have which would leave me in the same boat I'm in now.