VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1929-1932 Decent priced alternator for $100

I've been looking at 6v alternators. From what I've read through past posts I think I want to go with a 60amp. Most of what I'm finding online is in the $140 dollar range, though I've found a few for less. Is there a decent 6v alternator for around $100, or is the $140 one about the standard price for a good one?

Thanks

Brandon , why do you need 60 amps on a 1931 Chevrolet. Have you considered keeping your generator , and fitting an electronic control module to it.

I found the website with the modification.
Here is the link ,

delco regulator mod

I have used a Jim Peterson regulator in a '31 Delco generator for approx. 10 years. I switch the generator between the cars I drive on tours '28 & '31. Could not be more pleased with the performance. Don't have to remember to drive with lights on during the day to keep from cooking the batteries. One of the best investments I have made for these old Chevys. Still use the original cut-out despite Jim recommending converting it to a diode.

Chipper, the one I found listed was for a Model A and said for positive ground. Is this adaptable or does he make one for negative ground.

He makes a negative ground regulator. Seem to remember that one was for a Buick. Had never supplied one for a Chevrolet when I got mine. Has now supplied several.

I'm going to go with a 6v alternator. I'm just trying to figure out if the $100 are worth the money or if I should go with the $140.

A chat member here installed an alternator in his 1931 sedan, and it kept burning points out every couple of hundred miles. All that amperage has to go somewhere, and it usually goes to the weakest point in the electrical system. An original generator supplies approx. 18 amps , so 60 amps in nearly triple that.

Hello Vetteman61,
Jack39rdstr states that the problem is high amperage output, causing damage to batteries, points, and other components. It appears that if you still wish to go with a 6volt alternator to find out for yourself if this is true or not, commit to the $140 unit. If you take a chance on the $100 alternator and start having electrical issues, you might conclude that your problems are due to a low cost unit and not the amperage issues. With the $140 unit you'll be less likely to blame any problems on cost. Not knowing about electrical manipulation, I would guess that if it is possible to dampen amperage output yet maintain steady voltage, you might have a solution. Let us know how you solve this issue. Good Luck

I have a 6v one wire on my 31, also the same alt on my previous 48 and love them. Never a problem and to me, they are much easier on battery and electrical system.

The 60 amp output is the max that the alt will put out. Normal amp usage for just the ignition system is about 14 amps. You can add a bunch of electrical accessories and still have good charge, even at idle. Unless you have a problem with the internal regulator, that alt will only put out what is leaving the battery plus whatever is operating at the time (ignition system et.al.) For a good understanding (even for a dunder head as I am) go to Fifth Avenue Antique Parts and click on their alt setups on different alternators.

Best to ya.

Jim.

Have a look at this alternator on ebay at the moment , they have been building these for 30 years.
6 volt alternator 30-37 amps

Is the James Peterson regulator the same as this item in FS?
RW-396
GENERATOR CUT OUT REBUILDING SERVICE

Thanks,
Mark

No.

What size pulley would I want on a 6v alternator?

To suit a 1931 size fanbelt you will need a 5/8 to 3/4" as the pulley width measures about .680" at the top inside edge on an original pulley.

I bought my 6 volt alternator from Randy Rundle of http://www.fifthaveinternetgarage.com/, and that was back in 2005 and until this day its been working darn good hell in 8 years only 2 battery replacement and I installed from the fillinf station the 6 volt halogen conversion for night driving and its been worked darn fine, but thats on you if you want to keep the generator or the alternator

I measured the width of my belt and it was 5/8". I've noticed that when the sizes of the pulleys are listed they indicate a single size, except for the 5/8-3/4. If my belt is 5/8" wide what does the 5/8-3/4 size indicate? I know earlier it was explained I need to order the 5/8-3/4 pulley for a stock '31 engine, but I'm curious what the numbers mean.

Thanks,
Brandon

Both the 5/8" and 3/4" fan belt will fit the one size pulley. They would make the vee in the new pulley slightly deeper / higher so that both belts will fit. The 5/8" belt would sit slightly low in the pulley, and the 3/4" belt would sit slightly high in the pulley.

Oh, I see. Thanks for clearing that up.