what does "GM" alternator mean?

[Go Fleiter]

is it for Genral Motors cars?

Speedway Motors offers a beautiful one as # 82117 (can´t put a link here with my holiday equipment).

I dont doubt it would work in my Plymouth, but what is "GM"  here??

Greetings from the Netherlands!

Go

[nc plumber]

Yes, GM stands for General Motors.

[Go Fleiter]

And why ? Does it mean "GM only" ? It is not "made by GM", isn't it?

Will it work on a Plymouth?

All these parts usually are universally usable.

The fitting-in itself would not be a problem.

Edited August 25, 2020 by Go Fleiter

[Merle Coggins]

It's an alternator that was originally used in many General Motors vehicles, Chevrolet, Oldsmobile, Pontiac, GMC, etc. It has become a popular hot rodder's alternator because they are relatively inexpensive and available almost anywhere. 

Edited August 25, 2020 by Merle Coggins

[DJK]

https://www.ebay.com/str/HowardEnt?_trksid=p2047675.l2563

[JBNeal]

additional information - grey beard's thoughts on GM alternators

[Go Fleiter]

thanks to all!

  So, if I understood well, GM here describes an engineering style created originally by GM!

You see, Im not deeep enough in the tuning/ racing scene :))

Greetings!

Go

[greg g]

There are two types a 1 wire and a three wire.  The 1 wire is pretty much a universal application. As long as you are wiring for 12 v neg.  They are internally regulated but need to be spun up above idle to start them charging.  Simply do up a bracket, connect the wire to the battery through an indicator light on the dash and you are in business.  They are usually limited to 80 amps or so max so not really suited to cars with a heavy accessory load.  But for a simple car like the Plymouth with radio and heater and headlamps should be good to go.  The three wire needs a bit more in the way of electrical circuitry as it does get hooked to the ignition side to excite it's field windings and some are extrenally regulated.  But as noted the GM stands for both unit manufactured to General motors design specs, Ford and Mopar had their own specs and designs and some would attest a more complex circuitry wiring needs, making the GM style easier to adapt to older cars.

[Go Fleiter]

Thanks to all again!

I did not know of all these details!

Greetings!

Go

[Sniper]

3 hours ago, greg g said:

There are two types a 1 wire and a three wire.  The 1 wire is pretty much a universal application. As long as you are wiring for 12 v neg.  They are internally regulated but need to be spun up above idle to start them charging.  Simply do up a bracket, connect the wire to the battery through an indicator light on the dash and you are in business.  They are usually limited to 80 amps or so max so not really suited to cars with a heavy accessory load.  But for a simple car like the Plymouth with radio and heater and headlamps should be good to go.  The three wire needs a bit more in the way of electrical circuitry as it does get hooked to the ignition side to excite it's field windings and some are extrenally regulated.  But as noted the GM stands for both unit manufactured to General motors design specs, Ford and Mopar had their own specs and designs and some would attest a more complex circuitry wiring needs, making the GM style easier to adapt to older cars.

 

The GM alternator only came from GM as a three wire setup as far as I know.  The one wire is an aftermarket thing.  The stock GM alternator wiring is no easier or harder to setup than the stock Mopar setup.  I put a stock type Mopar alternator in my 51 because, well, it's a Mopar and it wasn't difficult.  I know nothing about Frods.

 

alternator mechanical install, used the original brackets

 

http://www.yourolddad.com/12-volt-conversion

 

You'd wire it up like an later dual field terminal Mopar charging system.  Ignore the blue stuff.

 

 

[Sam Buchanan]

4 hours ago, greg g said:

There are two types a 1 wire and a three wire.  The 1 wire is pretty much a universal application. As long as you are wiring for 12 v neg.  They are internally regulated but need to be spun up above idle to start them charging.  Simply do up a bracket, connect the wire to the battery through an indicator light on the dash and you are in business.  They are usually limited to 80 amps or so max so not really suited to cars with a heavy accessory load.  But for a simple car like the Plymouth with radio and heater and headlamps should be good to go. 

 

For clarification:

 

The one-wire alternator I have on my P15 is for 6v system (these alternators are available for either neg or positive ground) and doesn't require the inclusion of an indicator light. I don't know about the need to spin up past idle since my alternator is charging as soon as I look at the ammeter.

Edited August 25, 2020 by Sam Buchanan

[Go Fleiter]

Thx!

 

The indicator light is not needed for 1 wire alternators. There may be includet a resistor internally instead.