Gen to Alt Conversion - Easy?

[Stephenorf]

I think I want to convert the 312 in my 1959 Merc to an alternator setup. Other than mounting and aligning the alt to replace the gen, are there any other concerns I need to be aware of? I'm thinking it can't be as easy as a plug-and-play swithover...or can it?

Thanks in advance,
Stephen

 

[miker98038]

If it’s a 12 volt car already it’s pretty straight forward. But which alternator you choose will affect that. If it’s an internal regulator (3 or 1 wire) you’ll need to deal with that. If it’s a separate regulator, same thing. If you’re going way up in amperage output to run heavy electrical loads, the output wire all the way to the battery terminal will need to be appropriately sized. And you need to figure out how to get the “red light” to work too.

I’m not a big fan of 1 wires adapted to a different vehicle. I’ve seen lower voltage at the battery then I like on some. Depends on the wire length and gauge between the alternator and the battery.

But in most cases you don’t get into all of those items. Just something to be aware off.

 

[Ole Don]

On that car, it may be that easy. It is already twelve volt - ground, just make sure the hot from the alternator is in good shape and able to handle the load without heating up.

 

[Stephenorf]

If it’s a 12 volt car already it’s pretty straight forward. But which alternator you choose will affect that. If it’s an internal regulator (3 or 1 wire) you’ll need to deal with that. If it’s a separate regulator, same thing. If you’re going way up in amperage output to run heavy electrical loads, the output wire all the way to the battery terminal will need to be appropriately sized. And you need to figure out how to get the “red light” to work too.

I’m not a big fan of 1 wires adapted to a different vehicle. I’ve seen lower voltage at the battery then I like on some. Depends on the wire length and gauge between the alternator and the battery.

But in most cases you don’t get into all of those items. Just something to be aware off.

Hi, I was thinking of using an alternator from a 1965/1966 Mustang (289ci/302ci). It is a "standard" 3-wire hookup with an external voltage regulator. I think the ones I have laying around are all 55 amp alternators.

1966 Autolite alternator for a V8, 55A 15V External VR - I have a few and they all tested good at the local Autozone.

 

[Stephenorf]

On that car, it may be that easy. It is already twelve volt - ground, just make sure the hot from the alternator is in good shape and able to handle the load without heating up.

Yes, that's right....it is a 12v negative ground already. I'm wondering if I'll neeed to swap voltage regulators when I move from DC to AC?

Here's the type of DC VR that currently is working with the Gen setup....

And the type of VR that normally goes with the early Mustang 55A Alternator...

 

[miker98038]

I’m sure you’ll need to swap the regulator. Probably also marginal on the output wire, but that’s a guess. I don’t know the generator output. Typical #10 (10 gauge, American wire gauge standards) is 30 amp. It depends to some degree on the insulation ratings. But at least take a look what Ford used with those on the Mustangs.

 

[Gene F]

I have a 12V 1957 Skyliner, and have always wondered the same things Stephenorf. I am afraid of not getting straight answers, so I am leaving mine alone. One day I will meet up with one of the guys that has done this at a cruise-in that will answer my questions, and let me look at his/her car. I just hate finding things out the hard way as I age.

 

[Stephenorf]

I have a 12V 1957 Skyliner, and have always wondered the same things Stephenorf. I am afraid of not getting straight answers, so I am leaving mine alone. One day I will meet up with one of the guys that has done this at a cruise-in that will answer my questions, and let me look at his/her car. I just hate finding things out the hard way as I age.

Hi Gene, I agree. I'm not sure about the "quirks" of these old cars when going from 12V DC to 12V AC. Seems like it could be straight forward...but I'm often not suprised when things are not as expected. I was hoping someone here was familiar with the conversion process and could let me know what to watch out for/expect.

 

[Gene F]

Yes, things like the pigtail on the voltage regulator..... what regulator fits that pigtail? How do you get the GEN light to work after the conversion. stuff like thta that no one seems ot wanna answer. Most small time vendors/mfrs don't want to answer these questions, and when you look at their instuctions they often simply tell you how to bolt on the part. I need more than that!!!!!!!

 

[fordor41]

If it’s a 12 volt car already it’s pretty straight forward. But which alternator you choose will affect that. If it’s an internal regulator (3 or 1 wire) you’ll need to deal with that. If it’s a separate regulator, same thing. If you’re going way up in amperage output to run heavy electrical loads, the output wire all the way to the battery terminal will need to be appropriately sized. And you need to figure out how to get the “red light” to work too.

I’m not a big fan of 1 wires adapted to a different vehicle. I’ve seen lower voltage at the battery then I like on some. Depends on the wire length and gauge between the alternator and the battery.

But in most cases you don’t get into all of those items. Just something to be aware off.

We installed a GM alt on our '41 Ford with a 302. Local shop rewired for 1 wire. worked great. Have a '60 Ford 292 now with 1 wire alt. and it also works good. No messing with Voltage regs. 1 wire to the + on battery and good to go. If you can't find large enough wire to suit your needs run 2 wires together..

 

[Stephenorf]

I found this on another forum:

Seems the conversion in the link below is for an early Galaxy, but I would expect the details to be very similar to any early Ford. The article also apparenty addresses the GEN/ALT light issue.

http://www.galaxieclub.com/alternator-conversion.html

 

[5851a]

I used the complete Alt charging set up from a 65 Galaxie on a 56 Ford. The Alt, the wiring to the regulator and gutted the cars harness to get the resistance wire and charge bulb. The resistance wire just parallels the red light wire so if the bulb burns out it will keep charging. Worked great. The 65 was selected since it was the 352 donor for the 56 and had all the parts needed. If you do go the salvage route select a donor car with the red lamp and not the gauges as the harnesses are different. You will need to strip the entire harness to follow the lamp wire back to the ignition switch. There are easier methods but it was no cost for me at the time.

 

[KULTULZ]

I'm a PURIST, OK?

I don't speak DELCO, POWERMASTER, INTERSTATE or STANT. It is either FORD or it ain't.

Here is info on an OEM appearance install.

Carefully pick though unless you wear a BOW-TIE.

http://forums.y-blocksforever.com/Topic115656-1.aspx

No food fights please ...

- EDIT - FORGOT TO MENTION -​

I once had a photo of a 1G CONV and the guy had painted the ALT BLACK and put a GEN DECAL on it. From the top view, it was hard to distinguish the conversion.

- VERY TASTEFULLY DONE (IMO) -

 

[KULTULZ]

I was thinking of using an alternator from a 1965/1966 Mustang (289ci/302ci). It is a "standard" 3-wire hookup with an external voltage regulator. I think the ones I have laying around are all 55 amp alternators.

If you look @ the mounting boss, the ALT ID and AMP should be stamped there, unless it has been through a re-builder. You can (could) buy a kit to pump it up to 100A if needed.

 

[rotorwrench]

The alternators all have the internal diode bridge to prevent reverse current draw. The electro-mechanical voltage regulators were two pole types but have to match the current output of the alternator. They have a preset current limiter pole and a voltage regulator pole. The cut out relay that the early generator voltage controlers had (three pole units) is not needed on an alternator. Most generators were no more than 35 amp for the average automobile. The alternators are generally over 40 amps in output.

A person can use any one wire alternator since may can be set up to excite through a warning light. It just takes using the two unused wire connections. This one is for a GM 10si.
http://www.expeditionlandrover.info/Delco_Alternators.html

 

[Charlie Stephens]

Just curious, why do you want to change? Unless you have something that needs a lot of power I would keep the generator. Find a good shop to completely rebuild it and it should last 100K miles.

Charlie Stephens

 

[Stephenorf]

Just curious, why do you want to change? Unless you have something that needs a lot of power I would keep the generator. Find a good shop to completely rebuild it and it should last 100K miles.

Charlie Stephens

The reason I'm thinking about changing to alternator is because they are off-the-shelf available (plus I have a bunch of good used ones just laying around), and because on low RPM the gen seems to not put out enough power. Also, this is my first generator-powered car and I'm not as familiar with the generators. Lastly, I see a lot of older cars that have been "converted" to alternator, so I'm assuming there must be an intrinsic value to swapping to alt vs staying with the factory gen.

 

[dmsfrr]

. . . Lastly, I see a lot of older cars that have been "converted" to alternator, so I'm assuming there must be an intrinsic value to swapping to alt vs staying with the factory gen.

One practical reason...
When air conditioning and extra cooling fans are added more electrical power is usually needed.

 

[Gene F]

Try a retractable. Lot of current draw as that thing is heavier than you would think. Plus a car with a gen can often times see very faint pulses in the headlights at idle. I would like to convert my ignition to electronic, and I think the gen set up would be a bit hard on it. No oiling the bearing every season with an alternator.

 

[5851a]

Personally I would just stick with the known Ford parts. When you start going with the 1 wire things and something fails in a 1 horse town you can find a Ford 1G without too much trouble. You start asking for a self exciting regulator equipped 1 wire Case backhoe with a Delco alt you may be in for a wait. OT but case in point, heading out for 3600 mile trip, heard a loud squeal under hood, stepped on clutch and engine killed. G1 bearing seized. Coasted to a driveway, owner came out and asked if he could help. Asked if he had a Ford alt, he did since his brother in law had left his car there and he didn't ever care for him. Think it was from a 71 country sedan, that was in 81 and it's still on my 67. The price at the time was a 6 pack. Just stick with the Ford parts, JMO.