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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?

I got my chores done quicker than I thought and went to the garage.

I tried disconnecting the field wire at both ends and connecting a new wire to the alternator and VR field - no change. Needle still wiggles around and lights pulse. Looking closely, I do see some small amplitude wiggling in the under dash volt meter.

Next - put a piggyback terminal on the ignition side of VR and clipped a jumper wire back to the battery. Started the car and connected it to the battery +. Again no change - maybe even a hair worse. Pulled the factory ignition wire off the piggyback connector and the volt meter dropped to battery voltage and the amp meter dropped to a slight discharge but was steady.

I checked a couple circuits with my continuity checker but I’m not sure I can read resistance with it as I haven’t seen any change in brightness. I may need to get a rheostat out and play with it.

So, no change.
 
Ok, two more experiments I’ll try. It may take a couple days as we have bad weather moving in and I’ve got to move a bunch of furniture to move to make room for a switch over to another internet/TV provider.

thanks
Yep, too bad Matt isn't on board here. He is good with charging systems.
 
If it were me I would do some voltage drop tests to test the wiring and connections. All would be with engine running. The first would be between the battery neg. post and the VR base/ground. Next would be between battery pos. to the VR. ING. terminal.There are more you could do but these will make sure your pos. and neg/ ground at the VR are good.
I‘ve previously run a ground connected from VR frame to battery (-) with no change.

To summarize, I’ve cleaned about all connection I can get to and found no issues. Cleaned with DeOx and applied light coat of conductive grease NoOx. This includes: alternator, voltage regulator, starter relay, ignition switch plug/terminals, bulkhead connections - they still look new. Checked battery and it’s full and I charged it fully.
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There may be some older dielectric grease down inside the bulkhead plugs. I know I used it years ago after cleaning. Took alternator to an armature/alternator rebuild shop and they pronounced it fit. After removing some AC duct work out of the way I managed to lay fingers on the amp meter connections and they are tight. I had the cluster out a few years ago and connecting those two wire is something I focus like a laser on. I don’t think any of this circuit runs through the fuse box but I haven’t checked any connections on the back of it.

With a mechanical regulator I do have significant voltage loss from battery to VR field. But with an electronic VR the voltage loss is .72 volts, slightly over FSM of .52 volts but no where as bad as loss of 1.53 volts with the mech VR. I’ve tried 3 mech VRs and at least a couple electronic ones, both of the elect ones work well, but at well over 15 volts.
 
Do you have anything else on the keyed 12 volt circuit? Like an electric choke? At this point I would try another alternator and then a different battery. Something is not making sense.
 
I forgot in my summary the alternator guy suggested checking the body ground at the firewall. I did and even ran another heavy wire to a valve cover bolt.

Pnora - I’ve had the car quite awhile. I have the underdash voltmeter and gauge lights hooked up somewhere. I will need to get under there and refresh my memory. I think at the fuse box. And I have an Audivox FM converter under dash - but currently off. I’ll look.

Halifaxhops asked about swapping alternators with my 66 which are basically the same. Batteries are same too. Kind of a pain with the alternator on the 67 due to the AC mount and barely long enough dual belts on it. But we have several days of bad weather coming so I may not have much better to do then spend it out in the garage.

thanks
 
If you are running points, find an old style original mechanical regulator. I'm sure I mentioned this before, but every single regulator sold today for the 69 and older cars with electronic guts will regulate around 15 volts. Unfortunate, but true. I got so fed up with them that I converted my cars over to Delco style alternators with internal regulation.
Your statment attributable to the electronic voltage regulator is true due the circuitry design. It uses a NPN current sinking transistor application that regulates the field current of alternator with LESS external losses which results in a slightly higher output voltage. The electronic voltage regulator's internal voltage divider network is responsible for the controlling the switching transistor drive (on time). IMO...a few tenths of higher system voltage Is not a big deal. Newer battery's (AGM design and lead-calcium construction ..maintenance free design) have a slightly higher internal resistance which requires a slightly higher charge voltage. Just my opinion of course.....
BOB RENTON
 
Yes, I’ve seen those. So far I’m resisting the urge to drill another mounting hole (or two) in my firewall.
 
If you are running points, find an old style original mechanical regulator. I'm sure I mentioned this before, but every single regulator sold today for the 69 and older cars with electronic guts will regulate around 15 volts. Unfortunate, but true. I got so fed up with them that I converted my cars over to Delco style alternators with internal regulation.

Mine doesn’t. 69 style solid state off eBay. Runs like 13.4 or so. I have good wires and a rust free factory metal car. Might make a difference.
 
My Hemi, running stock mechanical regulator, stock alternator, hidden chrome race ECU and mopar electronic distributor. 13.8 v rolling down the highway... and running on the Stat.
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I read through the post, and it seems all the corrective action has been recommended and attempted with the same outcome.

In the beginning you were looking for a possible solution to the problem with an electronic regulator. Troubleshooting charging systems on aircraft with 12v systems over the years I have found a solution that works for me, and it includes Aviation devices, sensors, alternators & regulators | Zeftronics
They are not cheap, but when owners update their radio and navigation systems from the old analog gauges to glass cockpits some of the older automotive style (Ford, Chrysler, and GM alternator and generator) charging systems from the 60's and 70's, including old carbon pile RV's can cause problems you are describing and Zeftronics has been my answer.

These are also mounted under a seat or inside of the firewall on aircraft cabin side, so you could hide it and not give up your original look. Just keep the factory one mounded as an inop-unit.

You could at least give them a call. I always had very good luck talking to these guys.

Some of there Features:
  • Increased Regulator life
  • Reduced panel lights flicker
  • Protects against grounded alternator field
  • Identifies grounded field
  • Reduce trouble-shooting time
  • OVI also indicates a field-to-short fault & alternator off
  • Protects system loads against overexcited alternator
As everyone here knows, these electronic gremlins have challenged many of us.

At times you can find used units on ebay and some of the Beech, Piper, and Cessna aircraft owner sites.

Good luck and please post your corrective action. I would like to keep it in my troubleshooting notebook for future usage.

Blueskys
 
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Those are a bit pricey. Appreciate the info.

I‘m still thinking about switching alternators for a test. My 67 that I’m having problems with is a factory AC car so to put a single belt pulley alternator from my 66 on it I’m going to have to remove all the belts (4) and put 3 back on and the reverse the process when through. Not difficult, just a lot of wrenching.
 
I’m thinking holy water and exorcism.
 
You are not alone, I have had this same problem in my RR/GTX for the past year. I can’t figure it out. Good luck with the holy water, let me know if it works.
 
Years ago I owned a 71 Challenger. All of a sudden it started over charging. I cooked a few batteries. It would blow the caps off. Literally. I changed voltage regulators. Cleaned grounding sources. Added grounds here and there. Had it to 3 different garages. One was a Chrysler dealer. No one could find the problem. One day I was laying on the driver's side floor just looking to see if I could find anything, and I mean anything. I was looking at all the connectors, when I found the connector for the steering column to the main harness had a black streak in it. I tried to pull it apart. I could not budge it. The black streak was where the main hot wire connected. The heavy, what #10? wire. I said SHOOT. I disconnected the battery and clipped the wires on both sides of the connector, connecting them with a butt connector. I reconnected the battery and started the car. BINGO, it fixed my over-charging problem. I drove it for many years after that and it worked flawlessly. Your car is an older car if I remember correctly, so I am not that familiar with the wiring of the older cars. But check your hot wire going to your ignition switch, or possibly even the switch itself. I'm just another idea out there, but it's worth a look.
 
When I first got my 66 it had a bunch of electrical issues including a bad instrument VR, partially melted engine harness, & several melted bays in the bulkhead. One of the things going on (before the IVR would send the gauges full right) was the apump gaugecwas jumping around. It was after that that I found the partially melted harness and bulkhead and I concluded each one of those gauge needle jumps was a short occurring between the main alternator wire and others in the harness or the bulkhead. But then the needle was going between discharge and charge. I replaced everything on it.

This is different as the needle is staying on the charge side, even when I turn on the lights and the fluctuations increase. And the gauge is steady with the 15+ volts of the electronic VR but not with the lower 14+/- volt mechanical VR.
 
My amp gauge plus any voltage meter I hooked up to the battery / system would show a major charge all the time. It was not until I bypassed the bad connection in the wiring harness that everything went to where it should be.

The voltage meter would show up to 16 volts most of the time. Sometimes it was even more than that. I do not exactly recall what it was, but my brother is an electrical engineer and he was flipping out over the numbers. Unfortunately, he did not live near me to help me out at the time.
 
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