Very Confused!

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So to circle back on this.

We replaced the old (smelly) regulator with one from Napa and the meter is not twitching anymore.

Everything is charging within parameters.

@bloodyholly is watching it like a hawk.

Thanks for all the help.

Someday I’ll understand those schematics @Mattax but really appreciate them. I’ll go back through this thread and study some as this seems like some basic stuff I should know.
 
The shop that restored my '68 FS FB put an O'Reilly alternator and VR on the car. It bounces between 15 and 16V essentially all the time. I replaced the VR with an older chrome unit I had, and it was more steady in the 14 to 15V range. I would prefer steady voltage, but not sure that is the case. The O'Reilly alternator was a new Chinese knockoff of the Chrysler alternator. I would prefer the Chrysler unit with new bearings and diodes, but as long as this one works, I will keep it.

The VR can be checked for both function and approximate voltage regulation by using an ohm meter as per this video: The O'Reilly VR had 2.6 ohms across the pins and regulated too high. The replacement chrome box had 1.75 ohms resistance and was fine.

I would ground the alternator to the engine and run at least a 14-gauge ground wire from the VR to the back of the block just to be sure both are grounded properly. That is how the VR gets it voltage signal to regulate the output.

I made a mount for the electronic VR that bolted to the '68 firewall using 1/4" aluminum sheet stock cut to the dimensions of the electronic VR. Holes were drilled and tapped for 1/4-20 bolts. I used an old mechanical VR to determine the holes for mounting the adaptor bracket and used countersunk bolts to flush mount the aluminum plant to the firewall. The electronic VR bolted up fine, but the lower bolt was difficult to install due to clearance with the inner finder. A stud here would solve that issue.

VR and mounting plate with Ground Strap.jpg
 
The ground comment from your mech:

There may or may not be more to that. It might be that the body is not really well grounded to the battery. One way to insure this (battery main cable should be grounded to block) is to buy a 1 ft--1 1/2ft Ford style "starter" cable (eyelet to eyelet) and ground it to the engine block, and to the body. The master cylinder bolts work for that, and on a V8, the same holes are on the rear of the driver's head, which are on the front of the pass head. So you can find a short bolt and connect that cable there

Be sure the paint is scraped from the firewall for the VR mounting, that the bolts are not stripped, and you might scare up a couple of star washers. Does not matter much if they are internal or external star

Then we can go from there

I may not be here much, I am fighting a house fire situation.
I would like to add. I use dielectric grease at the ground ends after ensuring a good body and engine contact. That is the problem with cars and their computers today, bad grounds. Some cars have 10 or more of them.
 
I would like to add. I use dielectric grease at the ground ends after ensuring a good body and engine contact. That is the problem with cars and their computers today, bad grounds. Some cars have 10 or more of them.
Dielectric grease doesn't conduct electricity but it does protect against moisture that can cause corrosion. Use it sparingly.
 

Bloodyholly and Clementine, I am down in Auburn WA and can help sometimes with electrical issues.​

I do not always recommend the Amp gauge bypass but do sometimes recommend a Bulkhead by-pass or renew the brass connectors. I have a few spare male and female locking connectors for the Bulkhead plugs.
 
Reminder. Basic electric. Amps is CURRENT FLOW and Voltage is the driving push.

If the alternator is pushing 60 Amps and finds resistance at the bulkhead connector plug it will try to boost the voltage PUSH.

All the amps from the alternator go through the Bulkhead connector TWICE, once to the AMP meter on a 10 gauge wire, then through again on a 10 Gauge wire to the battery. These connectors have been known to get hot and melt the bulkhead plastic.

On many "Server Usage" vehicles like some trucks, Taxi's, Police.... They did a Bulkhead by-pass with two 10 gauge wires on a heaver connector that was a bit better weather proofed.
 
And a question that I did not see anyone ask @bloodyholly yet.

Are these replacement Alternators stock amperage or are they upgraded to like 90+ Amp. If you upgrade the Amp output then you must upgrade the wiring and Amm gauge.

I had an old chart from an old Dodge Service manual for when they put a Police Package on a stock 45 AMP amm gauge and upgraded the alternator to a 90 Amp for the "Bubble Machine" lights and radios. They placed like a 22 or 19 gauge "SHUNT" wire on the back of the Amm gauge. It was a Current Splitting device where half the current went thru the Amm gauge and half across the Shunt wire. The Amm gauge still showed "Charge" or "Discharge" The chart listed the different gauge wire needed for the Shunt by the upgraded alternator amount.
 
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Never discount old wiring either. What may look ok to the eye may be green or blue 6 inches or more under the insulation!
 
These are the type of connectors for the Bulk Head. The factory ones are very thin brass and are OK for 18-14 gauge. I have some heaver ones for the 12-10 gauge wires. Same connector GM and AMC used.

Bulkhead Connectors.jpg
 
Reminder. Basic electric. Amps is CURRENT FLOW and Voltage is the driving push.

If the alternator is pushing 60 Amps and finds resistance at the bulkhead connector plug it will try to boost the voltage PUSH.

All the amps from the alternator go through the Bulkhead connector TWICE, once to the AMP meter on a 10 gauge wire, then through again on a 10 Gauge wire to the battery. These connectors have been known to get hot and melt the bulkhead plastic.

On many "Server Usage" vehicles like some trucks, Taxi's, Police.... They did a Bulkhead by-pass with two 10 gauge wires on a heaver connector that was a bit better weather proofed.
Happened to me, melted bulkhead connection. Good place to check for corrosion.
 
Thank you for all the replies. I've been reading them and yeah...definitely learned a lot from this.
 
They're a good vender but for most Chrysler connectors use a Packard 58 style for the male terminal.
Also for some terminals (headlights for example, the wider terminals are needed.)
 
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