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Anyone know of a source for an “electronic” voltage regulator that puts out no more than 14.2-14.4 volts?

For an original 1970 electronically regulated charging system, it will be a round back dual isolated field alternator. All it takes to get a full field voltage number as described is a short to ground on the green field wire running from the VR to the alternator or a brush with insulators not installed correctly, shorted to the case to put the alternator in full field. You can throw as many VRs at it you like, won’t change a thing.
 
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Going back to the earlier part of my thread, I have an ERA Cobra I built some years ago that runs a dual point, early Ford alternator and electronic VR. I got it out today and finally put my voltage meter on it while running and it was right at 14.1-14.2 volts - perfect!! Geeez - you would think if they could do this for Ford they could do it for Mopars.
 
I have a Mopar (us) on coming from Summit. Way better quality and if that doesn’t work then I’ll go down the alternator road.
 
Going back to the earlier part of my thread, I have an ERA Cobra I built some years ago that runs a dual point, early Ford alternator and electronic VR. I got it out today and finally put my voltage meter on it while running and it was right at 14.1-14.2 volts - perfect!! Geeez - you would think if they could do this for Ford they could do it for Mopars.
The output voltage of of the alternator is determined by the VOLTAGE REGULATOR's internal voltage divider network that controls the internal switching transistor's on/off time, which controls the 0-6 volt output to tge alternator's rotating field and has NOTHING TO DO WITH THE alternator except to control the rotating field impressed voltage.....its that simple. Unless you have a electronic SCHEMATIC of the regulators for comparison, the results are speculation. The FORD regulator is just packaged slightly different. Just my opinion of course.....
BOB RENTON
 
I will say I never had this issue when I had the original dash and gauges. My issue then was the ammeter gauge wire connections getting hot,due in part to old crusty insulation on the studs. Same alternator & VR. The ammeter wires got joined and wrapped up,so I never knew what was going on with the charging system till the installation of the digital dash.
I’m feeling good about the better built VR from Mopar and like someone else said, I’ll pull the alternator and go to the repair shop and see what they can do.
 
The output voltage of of the alternator is determined by the VOLTAGE REGULATOR's internal voltage divider network that controls the internal switching transistor's on/off time, which controls the 0-6 volt output to tge alternator's rotating field and has NOTHING TO DO WITH THE alternator except to control the rotating field impressed voltage.....its that simple. Unless you have a electronic SCHEMATIC of the regulators for comparison, the results are speculation. The FORD regulator is just packaged slightly different. Just my opinion of course.....
BOB RENTON
I wasn’t talking about the alternator at all. I’m questioning why I can buy a early style Ford electronic voltage regulator that controls system voltage at 14.1/14.2 volts but nobody can find a early style Mopar electronic voltage regulator that will control system voltage at less than 15.2 /15.5 volts?
 
I wasn’t talking about the alternator at all. I’m questioning why I can buy a early style Ford electronic voltage regulator that controls system voltage at 14.1/14.2 volts but nobody can find a early style Mopar electronic voltage regulator that will control system voltage at less than 15.2 /15.5 volts?
If that's the case, the regulator controls the alternator's field voltage.....to that end, simply purchase a FORD voltage regulator and adapt it to the Mopar charging systen assuming compatibility OR dis-assemble a MOPAR UNIT and change the voltage divider network to suit your requirements........
BOB RENTON
 
If the alternator is outputting more than 15V something is wrong inside...
Time to pull the alternator off and take it to a qualified electrical shop for testing..

Just my $0.02... :thumbsup:
 
I’ve suggested several times to disconnect the VR, run the engine, verify there the full field condition goes away or not. If not, disconnect the green field wire from the alternator, try again, is full field condition still present, yes or no? Do a proper diagnosis.
 
If the alternator is outputting more than 15V something is wrong inside...
Time to pull the alternator off and take it to a qualified electrical shop for testing..

Just my $0.02... :thumbsup:
The alternators output voltage is controlled by the VOLTAGE REGULATOR. If the output voltage is excessive, it is HIGHLY unlikely that the regulator is fsulty......not the alternator. Taking the alternator to a qualified electrical shop.....not an auto parts store would be a waste of time snd effort ......prove this by disconnecting the lt green and blue wire at the alternator......just my opinion of course......
BOB RENTON
 
The alternators output voltage is controlled by the VOLTAGE REGULATOR. If the output voltage is excessive, it is HIGHLY unlikely that the regulator is fsulty......not the alternator. Taking the alternator to a qualified electrical shop.....not an auto parts store would be a waste of time snd effort ......prove this by disconnecting the lt green and blue wire at the alternator......just my opinion of course......
BOB RENTON
The challenge is most guys know little about the alternator/charging system...
So they start throwing parts @ it..
EZ enough to swap out a voltage regulator, but testing an alternator is a bigger challenge...
So taking it to a qualified electrical shop is my recommendation, and noting its voltage output @ various RPMs.. .
Note that we just fixed a buddy's Mopar where the alternator's output was causing his amp and voltage guages to fluctuate intermittantly..
Turned out his electronic voltage regulator internal power transistor was breaking down. Installed a new voltage regulator, all is well..

Just my $0.02... :thumbsup:
 
If the alternator is outputting more than 15V something is wrong inside...
Time to pull the alternator off and take it to a qualified electrical shop for testing..

Just my $0.02... :thumbsup:
Nothing wrong with the alternator - works fine at 14.2 volts with a mechanical voltage regulator. It’s the damn electronic voltage regulators!
 
I bought the 69 GTX and on the drive home I noted the gauge would flutter, and do some weird back and forth stuff. I put it on my punch list.

Decided I should just get a new look alike reg that was electronic and keep the mechanical one for a spare. I figured it wasn’t grounded good, but I like to travel with a spare in my roadside kit. I also dislike the bouncing on the gauge from the points opening on the old style. As a compulsive gauge watcher, it’s just a distraction that borders on irritating.

The mechanical gauge suffered from stripped screws and rusty holes, so I ran a ground wire straight to the battery. Put some tape around the bolts since it wouldn’t hurt the grounding with my wire and that allowed enough tightening. Was quicker than unbolting something on the block to ground to, could always change later when I had more time. New electronic reg worked well, no bouncing just as I wanted.

Died around 100 miles. eBay seller refused to acknowledge me. So back on went the old one, with the ground.

It worked well. Soon I was bothered by the switching so I ordered another electronic from different seller. I think it was the same thing as last guy sent. I installed it and it behaved funny. I was pissed and contacted the guy, explained the whole nine yards.

I was told the manufacturer said to never ground it to the battery. No reason given, I speculate it’s some sort of electrical noise it doesn’t like.

It works perfectly now. I told the seller they should put that in the paperwork. Maybe this will help somebody.
 
Looks like I will be taking the alternator out and heading for the repair shop tomorrow. Put in the Mopar VR today and no change on the meter at the battery and the digital gauge on the dash. At least they are agreeing with each other. The firewall on the RR.has the mounting plate that is all grounded up. Called the shop that does the Alt repairs and he said the high charge to the battery is…the voltage regulator and not the alternator. Baffles me to no end!!!!
Turning on the lights brings it down & dropping it in drive or reverse it will stay low 13-14v
Like I said…Baffling!!!
 
Looks like I will be taking the alternator out and heading for the repair shop tomorrow. Put in the Mopar VR today and no change on the meter at the battery and the digital gauge on the dash. At least they are agreeing with each other. The firewall on the RR.has the mounting plate that is all grounded up. Called the shop that does the Alt repairs and he said the high charge to the battery is…the voltage regulator and not the alternator. Baffles me to no end!!!!
Turning on the lights brings it down & dropping it in drive or reverse it will stay low 13-14v
Like I said…Baffling!!!
Baffling to me is that it has been suggested here several times to perform a couple of simple diagnostic steps that can easily isolate the exact cause, all without any acknowledgement of any kind. Do the diagnostics if you want to resolve the problem. Pull the connector off regulator, run the engine, is it still showing a full fielded voltage reading?
 
Is that full fielded voltage reading telling me that the alternator has an issue? Then I shall pull the fielding wire as well. Gotta try everything! Wish me luck and stay tuned
 
Is that full fielded voltage reading telling me that the alternator has an issue? Then I shall pull the fielding wire as well. Gotta try everything! Wish me luck and stay tuned
One step at a time, "disconnect the VR, run the engine, verify there the full field condition goes away or not. If not, disconnect the green field wire from the alternator, try again, is full field condition still present, yes or no?" Leave the blue field wired connected at the alt for this testing.
 
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Sounds good! My alternator has one field wire that’s kinda gray, and I believe the second field is grounded and of course the lead wire to the VR. Should that be any different than some who have 2 field wires that can be unplugged?
Thanks for your patience
 
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