generator vs. alternator

don-wi

Senior Member
The generator on my '47 is bad. The car is stock with the exception of having Pertronix electronic ignition. I am considering making the switch to an alternator. I know that the ignition would be happier with the added amps and stable voltage supply. I have looked at the Powermaster alternators that look like a generator, nice units but spendy. I have looked at the brackets to install a Delco one wire alternator and I'm sure they function good but when installed it looks out of place. Maybe painting the alternator black would look better? Anyone have experience either way? Thanks Don
 
I just installed one yesterday, looks good - have fingers crossed - time will tell
183613
 

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There's nothing wrong with a generator. If you've added a lot of stuff like power windows, A/C, stereos, hydraulics, air bags, etc - get an alternator. But if you're running mostly stock electrical accessories like lights, a heater, basic ignition and a 'normal' radio even, the stock generator puts out far more current than you need - even if you convert it to 12V.

A generator will charge a dead battery. An alternator will not. There's really nothing wrong with generators - modern cars went to alternators as the electrical requirements kept creeping up and for the size/weight, an alternator will out-produce a generator every time.
 
If you do the alternator setup, consider the three wire and not the one wire setup. Go to MadElectrical.com and read the section about one wire VS three wire alternators. Good information.
 
The generators on my cars were rebuilt when I got the cars, the A has been working for 40 years--untouched, the chevy truck with the delco alternator has been off and rebuilt 3 times in the 35 years I have owned the truck

The rebuilder that I used to get parts from considered the delco alternator most often used for 6V conversions one of the best ever made,---easy and cheap to rebuild, lasted long enough to get out of warranty, but not long enough that you didn't get a repeat customer

Many auto electric shops don't remember how, or want to fix a generator ---the local one here won't do anything 6V

An alternator needs to turn faster than a generator, the small pulley to make it spin faster puts more strain on a belt, belt wears faster, has to be tighter to prevent slip ---this puts more strain on the waterpumps -but you can change to ball bearing pumps---
Many "one wire" alternator always drain a little electric to keep them ready to charge (you might need a battery shutoff for when sitting)and sense the charging voltage from the 1 wire, not battery voltage(see above post about 3 wire alternators)
 
There's nothing wrong with a generator. If you've added a lot of stuff like power windows, A/C, stereos, hydraulics, air bags, etc - get an alternator. But if you're running mostly stock electrical accessories like lights, a heater, basic ignition and a 'normal' radio even, the stock generator puts out far more current than you need - even if you convert it to 12V.

A generator will charge a dead battery. An alternator will not. There's really nothing wrong with generators - modern cars went to alternators as the electrical requirements kept creeping up and for the size/weight, an alternator will out-produce a generator every time.

Good answer !!!!!! And the gen looks so cool .......
 
I've had very good luck with the Powermaster alternator. It looks like a generator and is engineered nicely for single wire connectivity. No doubt there are both positive and negative experiences out there with this unit as there are with most any solution. My experience hass been positive.
 
With an alternator you will have brighter lights, charge at idle or almost idle depending on the type alternator and pulley. If you go with the Delco have them put a 24 volt stator in it. It will charge real good at low RPMs. A few years ago a friend bought 2 Delco's from someone who provides them for Fords. After 2 weeks they removed them and gave them to me, they didn't like them. I tried one and didn't like the way it worked either. Talked to a generator/alternator repair shop and the old wizard said they could put a 24 volt stator in and would work good. The cost was $35.00, I had it done and it worked perfect with the stock Ford pulley and had the other one done also. This was on a 6 volt POS ground system. It would also work with 12 volts, the voltage regulator is what determines the output voltage. When a Delco is used on 6 volts the diodes have to be changed as well as the voltage regulator. The diodes change the AC to DC and also change the polarity. The voltage regulator contols the output voltage. On the 7 alternators I made I used a Transpo adjustable regulator and I can zero in on 7.5 volts. The box in the top of the picture is the regulator which has a small adjustment screw on the other side with a small hole in the rear cap to adjust it. G.M.
 

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With an alternator you will have brighter lights, charge at idle or almost idle depending on the type alternator and pulley. If you go with the Delco have them put a 24 volt stator in it. It will charge real good at low RPMs. A few .:pyears ago a friend bought 2 Delco's from someone who provides them for Fords. After 2 weeks they removed them and gave them to me, they didn't like them. I tried one and didn't like the way it work either. Talked to a generator/alternator repair shop and the old wizard said they could put a 24 volt stator in and would work good. The cost was $35.00, I had it done and it worked perfect with the stock Ford pulley. G.M.

This is very interesting, I have never heard of a 24 volt stator in a 12 volt alternator. That would properly fix my alternator that did not charge at idle.

I will probably put a generator back on because I think a alternator is petty darn ugly :o:o:o

I learn something on the barn forum everyday.
 
I want to stay with 6 volt / positive ground. I was told by a supplier that the Delco 10si can be built for 6 volt with positive ground. One of the things that I'm still investigating is the role of the original ammeter. I know that most of the kits use a one one configuration for the alternator. From what I have found the original ammeter should handle a standard Delco alternator, I just have to sort out the wiring and decide how to handle it. Looking at the wiring diagram for my '47 I'm not sure how the power wire from the alternator will work using the original path through the ammeter and on to the solenoid / battery. Thanks for all the information, Don
 
Don't know what's so ugly with an alternator. I have changed to 12 volt and think the alternator is great. Of course I have made other small modifications. Zeke
 

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I changed to a 8 volt alternator and battery, every thing works better.

Don,

Before you change to an 8 volt battery research it in the archives. I think you will find that the jury is still out on 8 volt batteries. My choice would be 6 or 12.

Charlie Stephens
 
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I think the Jury returned its verdict a long time ago on 8V batteries. Waste of time. Cure nothing. My choice is 6V Optima.
 
My '47 original amp meter works fine with my 3-wire 10SI Delco 55 Amp ALT. 55 amp is plenty for these vehicles, even if you convert to electric radiator fan(s). Regardless, always good to use relay's for your headlights and other high current draw items. Dan
 
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