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Alternator overcharging

Then there is the factory approach to beefing up the alternator to splice 1 bulkhead Packard terminal weakness, the mid-seventies C-body recall. Much safer than the “shunt wire” bypass.
 
What I described above is if you want to retain a stock configuration. Keeping the amp gauge. I think this is what 72RoadRunnerGTX did. He can explain what gauge (8GA) wire, Fuses and locations worked best for him. He is a proponent of the amp gauge. I think this one of his pictures.
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If you are going to do amp meter bypass.

Bulkhead and amp meter bypass.
Here are some examples of what can be done. Not saying what is correct for your application. Connecting to the starter relay circuit is electrically the same in this manner. But the the gauge of wire from the relay is not adequate. That's why it should be connected to the starter feed or directly to the battery.
Also a headlight relay circuit would be advisable. The main point of it is that the load is electrically connected to the alternator. That being said. Splice one also has to be feed from the alternator. The alternator never was a on a fusible link that feed splice one. It would be advisable to place one there. As it was said before the the diodes would or might blow before any damage . But why take a chance.
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What I described above is if you want to retain a stock configuration. Keeping the amp gauge. I think this is what 72RoadRunnerGTX did. He can explain what gauge (8GA) wire, Fuses and locations worked best for him. He is a proponent of the amp gauge. I think this one of his pictures.
Yes, that is the current Challenger project, now in the final stages of completion. Not so much a proponent of the ammeter, more that I understand it is purpose and why it’s there, as well, understand how to maintain/service it to continue to operate within its design limits and all while running all the loading I need/want. Don’t buy into to all the fear mongering and misinformation circulating for years relating to the Chrysler passenger car ammeter.

Example of my approach to electrical for these cars these days.
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That perfect, I will study all of this and do my homework, thanks a lot everyone for your help and your kindness.

Keep you informed !
 
Some additional information. Take note of the wire from the alt stud to fuse and then feeds to the starters feed. It can also go to the battery when doing a complete alt bypass. This is just a generic diagram. Don't get confused by the other wiring in photo.
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The stud for the red battery wire is what not to connect to. The gauge is not heavy enough. It has been done for convenance. That doesn't make it right.
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So, here's what I did :

I bypassed the Ammeter gauge like this (connections are not definitive, it's just for the test, I do not want to cut any stock wire until being sure it works) :
- Tied Red and Black Ammeter wires together behind the dash.
- I took the black alt wire from my old harness to make the link from the alt black wire to the red wire (the one pluged to the fuse link wire). (I took this old wire because I didn't want to put of the tape on the new harness.)

As you can see on the picture, I didn't bypass the bulkhead, is that okay ?

I haven't start the car yet, because I didn't check all the engine ground, if I understood correctly, I should have a braided strap from the engine to the frame rail, I faxed myself below the car, I couldn't see very well, but I found nothing. Can you, please, show me some pictures of where it should be ? It would help me search better.

Thanks you.

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At this point, it is better than is was. The bulkhead connectors are the problem as any of those connections. for now keep them clean and tight. Maybe later reroute bypassing bulkhead connectors.

You are now feeding all loads through the both battery and alt wire feed off of one fusible link. Keep that same ratted fusible link as is, it is ratted for the wire it was design for.

Now alternator is feeding all loads and charging battery at that connection. In essences you are feeding splice one that feeds all loads. T wo is better than one. I'm sure someone will see it different.

The next thing to do is remove or move loads from the original wiring. Such as a headlight relay circuit. The other is to install an AUX fuse box inside. Optional depending on you choice of options. Hear at this point might be the when the 2 bulkhead connectors to be abandoned. Disconnect, leave in place and heat shrink live ends.
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check the original Battery and alternator connections on the back of the fuse box.
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Thanks.

Started the car today, stuck around 15/15.5 at cold idle (1200 RPM, big cam).
Should it have worked at the point where I am (not to mention security, just speaking about voltage regulation) ? Or do I still have a problem with ground for the voltage regulator ? Because I looked under the car again, and I still didn't find any wire from the engine to the body.
 
This is where the factory ground is for the chassis. The battery negative and the headlight ground is there. Then there is the negative battery cable on the motor. Then the alternator mounting hardware is the ground for the alternator. The body is the ground for all others.

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It wouldn't hurt to put a ground strap from the motor to the firewall. That's what I did.
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This is where the factory ground is for the chassis. The battery negative and the headlight ground is there. Then there is the negative battery cable on the motor. Then the alternator mounting hardware is the ground for the alternator. The body is the ground for all others.

View attachment 146173

View attachment 146173 It wouldn't hurt to put a ground strap from the motor to the firewall. That's what I did.
I'm good for this ground, I cleaned the alternator ground too, I will try the ground strap, thanks !
 
The voltage looks to be about 1 volt high. But that could depend on the battery's state of charge ( That I would check) or the demands of the other components. It still should come back down when the battery is fully charged. 14.4 to 14.7.

Check the field wires from regulator to the alternator. Connect jumper, 2 wires to the voltage regulator in the same manner as there connected originally. If you can put them in the plug of regulator and do the same on the alternator. Leaving the original wires in place.
When doing a continuity check on the original wires. It doesn't always show true results.
 
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Battery Hydrometer Readings Chart​


State of ChargeSpecific Gravity Values for Temperate ClimatesSpecific Gravity Values for Tropical Climates
Fully Charged1.250 – 1.2801.210 – 1.230
75% Charged1.220 – 1.2401.190 – 1.210
50% Charged1.190 – 1.2101.160 – 1.180
25% Charged1.160 – 1.1801.130 – 1.150
DischargedBelow 1.160Below 1.130

The one thing that is overlooked is: When the specific gravity reading differs 50 or more between cells the is a problem with the battery.

Also at 1.125 it's an anchor it's never coming back!⚓

It will and still work for a while.

Factors Affecting Specific Gravity Readings​

Several factors can influence the specific gravity readings of a battery:

  • Temperature Considerations: The specific gravity of a battery’s electrolyte can vary with temperature. In colder climates, the specific gravity might be slightly higher, while in hotter climates, it might be lower. Always consider the ambient temperature when interpreting readings.
  • Electrolyte Strength in Extreme Climates: In extremely cold or hot climates, the strength of the electrolyte can be affected, leading to variations in specific gravity readings. It’s essential to be aware of these variations and adjust maintenance routines accordingly.
  • Tips for Accurate Readings:
  • Always ensure the hydrometer is clean and free from any residual electrolyte from previous readings.
  • Take readings at a consistent time, preferably when the battery has been at rest.
  • If unsure about a reading, it’s always a good idea to take a second or even third reading to confirm.
 
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I have an Optima red batterie, checked by a pro shop just a few weeks ago, charged yesterday, she was at 12,7 before the start, 12,9 when after 30 secondes of idling. I think the batterie is not a problem
 
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