GM Alternators

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Talking about the one wire hook up and internal regulator, I don't remember if it was my '89 or '98 dodge pick up had a alternator with a built in regulator and if it went bad the alternator had to be replaced as the regulator was built in and at a cost of around $300.
 
My rewound CS-144 alternator identifies as a Mopar alternator, because it's in one and I wrote Mopar with a black sharpie on it before I painted it matte black.

It not a 1-wire. It senses voltage at the battery that's mounted in the trunk, puts out 115 amps at a slow idle and peaks at over 250 amps at a fast idle. It also has an externally mounted HD Bridge Rectifier and bolts right in with a simple bracket change.

Been to some pretty big shows with the car and no one has ever noticed.

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Talking about the one wire hook up and internal regulator, I don't remember if it was my '89 or '98 dodge pick up had a alternator with a built in regulator and if it went bad the alternator had to be replaced as the regulator was built in and at a cost of around $300.
Those both had the regulators built in to the computer- the '89 would have an SBEC and the '98 would be a JTEC. If either one of those fail, an external (IE the old Mopar electronic voltage regulator) regulator can be wired in instead of replacing a costly, and potentially unavailable, computer.
 
The only issue with them, is if the most fragile piece of the charging system is inside the alt, (the hottest, shakiest/nastiest location) and it fails, insteada just undoing 2 wires, 2screws and replacing the $15 reg on the firewall, - you'll have to remove alt to replace the ($$ ?) reg that's inside, - if you have the tools and knowledge, if not, you gotta take it somewhere to get it repaired which won't happen right away .
You know it'll fail the nite before/day of an event, so needing it now, means a whole new big $$$ alternator R&R, steada the regulator on the firewall.
jmo
Actually the one I bought was like $45 and has a lifetime warranty. This car sat for around 8 years with the first one wire alternator on it and they replaced for free. One wire and 2 bolts and its off. I bet I could change the alternator faster than changing a factory voltage regulator...lol.
My blue Duster had massive charging issues in its past life, so bad it blew the headlights out of it so, the last thing I was gonna do was trust the old Chrysler system.
 
Yep GM 1 wire, no more dim lights at idle.

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Actually the one I bought was like $45 and has a lifetime warranty. This car sat for around 8 years with the first one wire alternator on it and they replaced for free. One wire and 2 bolts and its off. I bet I could change the alternator faster than changing a factory voltage regulator...lol.
My blue Duster had massive charging issues in its past life, so bad it blew the headlights out of it so, the last thing I was gonna do was trust the old Chrysler system.
I need to buy a bolt on conversion for my 76 Power Wagon before current OEM unit goes out - can eliminate some issues I'm having in the process.
 
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I've only used cs130's (105a)on all my builds (BB,SB,G3), technically a 2 wire, you already have the "exciter wire", just connect the blue wire from the ballast resistor to the vr to the green stator wire from the alt to the vr , when you remove it (the vr). A
I need to buy a bolt on conversion for my 76 Power Wagon before current OEM unit goes out - can eliminate some issues I'm having in the process.

dd the required inline resistor (available with the connector),bypass the bulkhead with at least 8ga. cable to the battery. they are cheap and readily available, will accept both v and multi groove (serp) pulleys. the first BB I did I used the factory brackets, same with the first SB, then CVF came out with a bracket set and complete kits. If it's a bucks down thing and you're interested ....1992 suburban 1500 5.7 105a. and change the pulley to a gm v groove. here's a pic of the mock up, the triangle brackets offset is flattened out
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You can buy the 1 wire set up in a Mopar case, I have one on my Duster.

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And since my latest project, a 66 Ford Fairlane came with a generator! I stepped way up and made life simplier with a Ford one wire internal VR alternator! OK, so I still run points!!!! :BangHead: :thumbsup:
That's odd.. a jenny? Honestly never heard of that and I've had my 67 Lane 30 years & been to a lot of shows.
 
I am not sure when hanged over to alternator or maybe I am thinking of my 64 Comet with the generator.
Sounds right.. think 63~65 timeframe was when they switched to alternators.

Looked into a 1 wire replacement for my 74 Challenger but they all seem to come with a pressed on single groove pulley. Ended up with a Powermaster 95A. The fans on my radiator alone can draw 70A at startup.. still would like a bigger 1 wire.
 
The only issue with them, is if the most fragile piece of the charging system is inside the alt, (the hottest, shakiest/nastiest location) and it fails, insteada just undoing 2 wires, 2screws and replacing the $15 reg on the firewall, - you'll have to remove alt to replace the ($$ ?) reg that's inside, - if you have the tools and knowledge, if not, you gotta take it somewhere to get it repaired which won't happen right away .
You know it'll fail the nite before/day of an event, so needing it now, means a whole new big $$$ alternator R&R, steada the regulator on the firewall.
jmo
The thing is...the mopar ones fail more than these do. I think in the first 8 years of having this car, I had 2 of them die on me. Then the replacement somehow had a powder coated case so I ended up making my own ground wire to get it to work.

The mopar alternators also make almost no power at idle. And they're kind of prone to having issues with the isolation on the field wires and then either not working or overcharging.

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This $50 parts store 12SI has outlasted 2 Mopar alternators and 2 regulators. It's a 3-wire which I still recommend that you do so it runs the system as designed. With electric fans, Aeromotive A340 pump and EFI it's doing well. Only a 78 amp model with an option to go bigger, there were OEM 94A and many upgrades past it. The 6 GA wire helps with the efficiency though I didn't originally have this.
 
Leverage what is simple and works best. I would prefer a modern Nippondenso alternator, like I see on my later Mopars (2002 newest), indeed most cars today. They output amazing current for the small size and replacement brush kits are easy. Some have an internal Vreg, but my Mopars still use an external Vreg, which moved inside the engine controller in the 1980's. When that circuit fails, Dodge truck owners install a 1970's Vreg rather than change the controller. For my old Mopars, I would prefer an internal Vreg for simplicity, but don't know what brackets and pulleys are available.

Some GM alternators are strange. My 1985 M-B uses a GM-type Bosch alternator, which many term "Motorola-style". Like a 1970-80's GM, it has an internal Vreg which must "boot-up" its power generator. That comes via the small current in a dash bulb. Indeed, my Owner's Manual says that if the dash bulb doesn't light on key-on, drive immediately to the dealership (for emergency bulb replacement) since the alternator won't be charging. Since I changed to LED bulbs, they don't give enough boot-up current, but when I rev over 1000 rpm the alternator boots-up due to residual magnetism (once aged). I know this all sounds bizarre to a Mopar guy, so google-check before you fuss I'm wrong.
 
The thing is...the mopar ones fail more than these do. I think in the first 8 years of having this car, I had 2 of them die on me. Then the replacement somehow had a powder coated case so I ended up making my own ground wire to get it to work.

The mopar alternators also make almost no power at idle. And they're kind of prone to having issues with the isolation on the field wires and then either not working or overcharging.

View attachment 1716191513
This $50 parts store 12SI has outlasted 2 Mopar alternators and 2 regulators. It's a 3-wire which I still recommend that you do so it runs the system as designed. With electric fans, Aeromotive A340 pump and EFI it's doing well. Only a 78 amp model with an option to go bigger, there were OEM 94A and many upgrades past it. The 6 GA wire helps with the efficiency though I didn't originally have this.

I still service a buncha these vehicles over decades, all kinda owners/ drivers/ stereos/amps, - a couple are daily drivers.
You know how many regs I put on in the last, hmm decade, one.
Alternators, - none, - I have put brushes and bearings in 3 or 4.
My own vehicles/kids , none in decades, or since built .
I'm sitting on a wooden chair (embracing it, lol)
Cheers .
Who cares if the alt doesn't put out at red lights with appliances, wipers, heater on, - the car doesn't care .
Thats what the battery is for, ballast, and if you notice, 50+ years later, stock ones are still running around.
 
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Actually, it doesn't--or didn't. The original Delco integrals back in the day were 3 wire, just like Mopar.

And I'll poke in my usual warning:

DO NOT stick a huge, great big, not to mention quite large "one wire" on there without properly sizing the charge wire, and that means either upgrading or bypassing the ammeter circuit.
Agree with you 110%, and I can't resist poking in my usual warning that adds to yours. More charging current through the firewall connector often melts the connector as a result of contact resistance heat. The original alternators were 35A. Plus, most people add higher current loads such as higher power headlights, amps, etc, which adds to the current through the firewall connector. I don't run charging wire through the firewall, I connect them to either the starter, the starter relay, or the battery, and then run a separate wire through the firewall, through a plastic grommet. Even a reman mopar alternator will cause a heating problem because they are upgraded to 55A.
 
I still service a buncha these vehicles over decades, all kinda owners/ drivers/ stereos/amps, - a couple are daily drivers.
You know how many regs I put on in the last, hmm decade, one.
Alternators, - none, - I have put brushes and bearings in 3 or 4.
My own vehicles/kids , none in decades, or since built .
I'm sitting on a wooden chair (embracing it, lol)
Cheers .
Who cares if the alt doesn't put out at red lights with appliances, wipers, heater on, - the car doesn't care .
Thats what the battery is for, ballast, and if you notice, 50+ years later, stock ones are still running around.
Agreed. If your alternator keeps your battery charged over a week of driving, it is doing its job. Relatives and neighbors had trouble with that in several cars (Mopar and GM) when I lived in intown Atlanta. I found they were making many short 2 mile trips which wasn't giving the alternator time to recharge for what starting used. That is a case for an alternator which puts out more current at idle, or perhaps connect a charger every Saturday night.

Too many people here worry and over-do the alternator. They add up motor ratings for things like an electric coolant fan and decide they need a 200 A alternator. That is usually just a brief starting surge current for the fan, plus it doesn't run all the time. If too much current and you don't similarly up the wiring, you risk melting wires and connectors, especially under-dash if you don't perform the "MAD Bypass" to keep the newly-high alternator off you dash ammeter.
 
I still service a buncha these vehicles over decades, all kinda owners/ drivers/ stereos/amps, - a couple are daily drivers.
You know how many regs I put on in the last, hmm decade, one.
Alternators, - none, - I have put brushes and bearings in 3 or 4.
My own vehicles/kids , none in decades, or since built .
I'm sitting on a wooden chair (embracing it, lol)
Cheers .
Who cares if the alt doesn't put out at red lights with appliances, wipers, heater on, - the car doesn't care .
Thats what the battery is for, ballast, and if you notice, 50+ years later, stock ones are still running around.
Glad you have had better luck.

Additionally before I bought the car the alternator had melted the dash harness due to being stuck on full field

My friend has a 1971 Demon and the alternator that was with the car failed and the replacement also failed within a year. Now it's at a 12SI delco like mine for 5 years with no issues once again.

I do actually care about it working at red lights, it should at least maintain 12.8V -> same as a fully charged battery with the headlights and wipers on...and in my case the EFI fuel pump and the fans. Anything worse is not great. When you want to go someplace with traffic at night its needed. The battery should only get drawn from for miliseconds during transient and also during starting and that's it. Its not an original car any other way so I use things that work. Unlike many of the other things it was also really inexpensive.

Like I said this is a 78 amp alternator, but it can pretty easily put out 50A at idle which is vastly better for the load needed.
 
I am somewhat dismayed by some of the comments here. Some folks might read these and conclude that mopar alternators bad, "1 wire" magically good."

I owned my first 69 RR in 1970 for a short time, then my 70 in about early 72. By about 75 or 6 I had a clapped out 64 FJ-40 Landcruiser with a 360 swapped in, then later a 340. I at first had a Mopar 70/ later style alternator regulator, and then, later, one of the big 105A big frame Mopar units, with the same flat Mopar electronic regulator.

The day I sold the 70RR and at the time I pulled the engine from the FJ-40, they both had original OEM Chrysler regulators. The one of the Landcruiser was a Chrysler junk yard unit

Here is the truth

1..."1 wire" are not some magic bullet. MOST OF the troubles with Mopar charging systems are IN THE HARNESS, bulkhead connector, or even voltage drop right in the ign. switch.
2... Many other problems are due to simple confusion between the older grounded field (pre 70) or isolated field (70/ later)

3...Other problems come from POOR REBUILTS which often come with an (incorrect) shorted field connection, causing either harness damage or "full field" output

3...As mentioned, the bulkhead connector is a huge problem WHEN using LARGER alternators and or INCREASED load, such as pumps, fans, or even big stereo amps

I DO AGREE that the older Mopars can be poor performers at low RPM. Actually, they are no different in this respect than the earlier Ford/ GM alternators, or at least not by much

As to the "magic bullet" effect of 1 wire alternators

IF YOU PUT a "1 wire" outfit on ANY rig, make CERTAIN that the charge path---ALL OF IT, EVERY SINGLE terminal and wire, from the alternator to the battery, IS ABSOLUTELY PERFECT, and OVERSIZED That is an absolute MUST

The other issue I have with "1 wire" is that it complicates disconnect hookups IF YOU trunk mount a battery, and then show up at NHRA. I've discussed this before. Leaving a large charge wire HOT all the way from the alternator to the battery IS NOT IN MY OPINION, either the spirit of the disconnect rule, NOR IS IT SAFE if YOU are the guy hanging in the harness hoping help will arrive, before the welding cable to the alternator burns something down.

IF you trunk mount a battery, I urge you to do whatever necessary to kill the alternator charge wire for safety


Now before you think I am just plain "again" these, the old Farmall has had a Delco "1 wire" hanging on the thing since the day it arrived here.
 
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