Ammeter pegged but voltage at 14v

[70LemonTwst]

Howdy, Howdy- I've got a new issue that has got me scratching here. Was out driving my '70 Satellite/RR conv and found that the Ammeter gauge was arching heavily while driving. Took the car home immediately and found that the stud on the alternator was loose. Tightened it up and now my Ammeter gauge is consistently reading a heavy overcharge. Needle is pegged or nearly pegged during idle.
Car @ idle, meter on the alternator power pole reads 14.6v.
Meter at the battery also reads 14.6v. Which to me indicates that the power being returned to the battery is within spec.

I've got 2 brand new voltage regulators plus my old one all producing the same result. Alternator was tested good at Napa.
All the wiring was just redone (by me...so yeah, there's that) but car ran fine for several drives after the engine side harness was implemented. I've confirmed that the field wires produce expected results with the ignition off (no volts on either), ignition on/not running (blue field shows high volt, green shows low volt).
Ammeter gauge was reconditioned earlier this year. Did the power arch'ing damage my ammeter gauge? Maybe it needs recalibration or what the heck am I missing here?

Since this overcharging has started the Ammeter gauge stays in the pegged position regardless of whether or not there's power. Is that normal?

Appreciate any guidance from you guys & Thanks.
Matt

 

[toolmanmike]

14.6 is pretty much maximum charging voltage for a Mopar system. Remember, you are measuring volts at the back of the alternator but your gauge is seeing amperage. It sounded like you fixed the problem, now don't run the car but instead, charge the battery with a charger.

 

[70LemonTwst]

14.6 is pretty much maximum charging voltage for a Mopar system. Remember, you are measuring volts at the back of the alternator but your gauge is seeing amperage. It sounded like you fixed the problem, now don't run the car but instead, charge the battery with a charger.

Thanks Mike. I have put the charger on the battery & even with the battery fully charged the Ammeter overcharge condition persists.

 

[dadsbee]

Are you saying the needle STAYS at full even with the key off, not running? If so you damaged, or disturbed the static positon of the needle when you tightened the wire lug.

 

[70LemonTwst]

Are you saying the needle STAYS at full even with the key off, not running? If so you damaged, or disturbed the static positon of the needle when you tightened the wire lug.

Yep...that is correct Sir. My needle stays high even with the battery disconnected.

 

[toolmanmike]

Yep...that is correct Sir. My needle stays high even with the battery disconnected.

View attachment 1192048

Yep, you need a new gauge.

 

[70LemonTwst]

Happy Days! Guess I'll be tearing into the cluster once again. Really appreciate the help Mike & Dadsbee. I'll post back to this thread when I get the gauge installed. Enjoy the day ahead.

 

[dadsbee]

Or a dissection at least. You probably spun the connection lug, which twisted the movement to where you have it. Static it should sit neutral. Possible you can fix it.

 

[PRND21]

Now that you’ve got that problem straightened out, the question now is, why are you still using an ammeter?

 

[hunt2elk]

Now that you’ve got that problem straightened out, the question now is, why are you still using an ammeter?

Holy smokes, are you trying to cause Nacho to have a heart attack, lol?

 

[70LemonTwst]

OK, pulled the cluster out. Removed the ammeter gauge from the housing. Very simple mechanism. You guys are correct it was just whorked because of the arc'ing. Just moved the little pendulum in there a few times and it started correcting itself to center. Put it all back together...worked like a champ. Crazy.

And yeah...I'm hanging old school for the time being. This issue almost pushed me over the voltmeter edge but alas it started working again.
Thanks for all the help.

 

[72RoadrunnerGTX]

...the question now is, why are you still using an ammeter?

Ok, I’ll bite, why should he not run an ammeter? Haven’t seen a good ammeter thread here in the last week or two.

 

[Mopars & Missiles]

Ok, I’ll bite, why should he not run an ammeter? Haven’t seen a good ammeter thread here in the last week or two.

Agree, there's not a damn thing wrong with an ammeter in a stock or nearly stock Mopar. Corrosion at the bulkhead connectors TO the ammeter, now that's a different story.

Another issue is, if you've ADDED a bunch of aftermarket electrical loads to the original stock electrical system, then you may want to re-evaluate the stock wiring/ammeter setup as well. (Once again, bulkhead connectors are the main concern, not the ammeter itself.)

 

[WileE]

Oh, no... not another Ammeter vs. Voltmeter

Ok, I’ll bite, why should he not run an ammeter? Haven’t seen a good ammeter thread here in the last week or two.

Troublemaker............

 

[RJRENTON]

Oh, no... not another Ammeter vs. Voltmeter

Troublemaker............

GADZOOKS......and all other expletives that express personal frustrations.....one of these days, the old FBBO site server is going to EXPLODE.......
BOB RENTON

 

[Studio70]

Agree, there's not a damn thing wrong with an ammeter in a stock or nearly stock Mopar. Corrosion at the bulkhead connectors TO the ammeter, now that's a different story.

Another issue is, if you've ADDED a bunch of aftermarket electrical loads to the original stock electrical system, then you may want to re-evaluate the stock wiring/ammeter setup as well. (Once again, bulkhead connectors are the main concern, not the ammeter itself.)

 

[beanhead]

....one of these days, the old FBBO site server is going to EXPLODE.......
BOB RENTON

Ammeters will probably get the blame for that one too!

 

[Robbins]

Now that you’ve got that problem straightened out, the question now is, why are you still using an ammeter?

I still use mine....in my 64 and my 86. A little preventive maintenance goes a long ways...just saying.

 

[toolmanmike]

View attachment 1194439 View attachment 1194440 View attachment 1194441

What a rat's nest!

 

[Should be playing golf]

Ammeters were fine when these cars had reasonably new and clean (no rust/corrosion, etc.) bulkhead connectors. Best thing to do is by-pass that potential weak spot with a direct 6/8 ga. red line from Alt. to Bat. All accessories tapped into the wire from bulkhead to ammeter will stay put and work fine, but heavy bat. charging will flow through the new heavy line and not the bulkhead connector, saving a total melt-down.