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Jumping alternator gauge

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74 Charger all original 360 4 barrell. Lately I've been seeing my alternator gauge sporadically jump all the way up to and almost past the "C" on the gauge and then drop back to the normal middle of the gauge between the "C" and "D". Lights and dash brighten up when it jumps up , then settle back to normal. Doesnt happen when more throttle is applied, just sporadically. Alternator? Voltage Regulator? Any help is appreciated, thanks!
 
74 Charger all original 360 4 barrell. Lately I've been seeing my alternator gauge sporadically jump all the way up to and almost past the "C" on the gauge and then drop back to the normal middle of the gauge between the "C" and "D". Lights and dash brighten up when it jumps up , then settle back to normal. Doesnt happen when more throttle is applied, just sporadically. Alternator? Voltage Regulator? Any help is appreciated, thanks!
Check the bulkhead connector.

There might be wires that have melted into others
or intermittent connections.

If no visible signs of wires melted, then pull the 3 connectors off from the engine compartment, clean each spade lug with very fine sandpaper, and coat with dielectric grease.
 
Could be the first signs of your voltage regulator going south. Check and make sure all your grounds are clean and tight.
 
I have disconnected the factory amp gauge on my last few cars. The factory gauge is the weak link in the electrical system. Disconnect the two terminals and bolt them together. Make sure you wrap the bolted connection in electrical tape. Then install an aftermarket voltmeter.
 
I have disconnected the factory amp gauge on my last few cars. The factory gauge is the weak link in the electrical system. Disconnect the two terminals and bolt them together. Make sure you wrap the bolted connection in electrical tape. Then install an aftermarket voltmeter.
Let me see if I understand this, the ammeter successfully alerted the driver to abnormal fluctuations in current flow in the charging circuit, as designed, and the recommendation is to bypass the ammeter and install a voltmeter? The factory ammeter, with tight, clean connections and good insulators is not the weak link in the original passenger car design of this time. Packard connectors and undersized wiring in the charge circuit are the weak points well before any ammeter issues. That and lack of/or poor general electrical maintenance to any of these circuits for some 50+ years.

With these symptoms, need to be looking for loads that have been added to the battery terminal that should not be there on a car equipped with a functional battery ammeter, lose or poor connections anywhere in the charging circuit, at the battery, starter relay, fusible link, bulkhead connectors, alternator stud, and yes, the connections at the ammeter as well. Internal battery issues can create these fluctuations as well. Sounds to me the ammeter is doing exactly what it was designed to do.
 
Let me see if I understand this, the ammeter successfully alerted the driver to abnormal fluctuations in current flow in the charging circuit, as designed, and the recommendation is to bypass the ammeter and install a voltmeter? The factory ammeter, with tight, clean connections and good insulators is not the weak link in the original passenger car design of this time. Packard connectors and undersized wiring in the charge circuit are the weak points well before any ammeter issues. That and lack of/or poor general electrical maintenance to any of these circuits for some 50+ years.

With these symptoms, need to be looking for loads that have been added to the battery terminal that should not be there on a car equipped with a functional battery ammeter, lose or poor connections anywhere in the charging circuit, at the battery, starter relay, fusible link, bulkhead connectors, alternator stud, and yes, the connections at the ammeter as well. Internal battery issues can create these fluctuations as well. Sounds to me the ammeter is doing exactly what it was designed to do.

You don't have to be such a smart ***. I am just suggesting another thing to try if the items that have already been mentioned don't work. It makes sense to try the obvious easy things first; but it's been my experience that the first thing that you try, might not fix the problem. Years ago, I had a similar issue with a '70 Coronet. After I checked every electrical connection, ground, the alternator, and the voltage regulator, the ammeter still did what the OP described. Then a friend gave me a copy of an article written by some guy named Mark Hamilton which starts on page 5 of this link.

http://www.mopar.org/MMCA/Newsletters/JAN_2009.pdf

Long story short, the problem for me ended up being the 40 year old, (at that time) ammeter. I disconnected it, bolted the terminals together, and that ended my electrical problem. Just sayin'.
 
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I’m well aware of the so-called “Mad Electrical” article addressing Dodge trucks from late seventies thru the eighties with a plastic framed ammeter. You’ve linked an apparent reprint. It’s been debated here for many years. As it relates to passenger car metal framed ammeter construction in the sixties and early seventies, the article does not apply on several key points. And while discussing other general electrical connection weaknesses in the original design, the author fails to address the original intent and purpose of the battery ammeter design, or the information advantages of the battery ammeter over a simple voltmeter. Several, and often repeated, blanket statements in this article are just dead wrong.

More likely, your 40-year-old ammeter terminals loosened up over 40 years, allowing resistance to build under the internal stud head to bus connection. Heat may have built up, insulators may have lost thickness, or become heat damaged, or were over tightened at some point resulting I the same outcome. Pretty common really, as nothing about these cars was ever designed to last 40+ years without being maintained adequately.
 
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if your gauge is warning you about a problem check whats the problem is the correct way to do it, not eliminate the gauge which is warning you.

is like get a car with a Check Engine warning light and to fix it you remobe the bulb light... fixed!!! you won't have to deal wit the problem anymore... right ?

Or to talk in our cars "language". Get the BRAKE cluster light on suddenly while driving, and you fix it disconecting the brake fluid distributor switch wire... right?

P.S.: I don't care what Luke Skywa... I meant Mark Hamilton posted on that link has to say.
 
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@Nick Galluscio please, do yourself a favor... this has being discussed recently ( actually some of us have being discussing this for maybe 10-12 years, maybe more ), so must be on same board page. Read some of the threads about.
 
if your gauge is warning you about a problem check whats the problem is the correct way to do it, not eliminate the gauge which is warning you.

is like get a car with a Check Engine warning light and to fix it you remobe the bulb light... fixed!!! you won't have to deal wit the problem anymore... right ?

Or to talk in our cars "language". Get the BRAKE cluster light on suddenly while driving, and you fix it disconecting the brake fluid distributor switch wire... right?

P.S.: I don't care what Luke Skywa... I meant Mark Hamilton posted on that link has to say.
I don't think that you quite understood what I was trying to say. I did not say to disconnect the ammeter because you don't like what it is telling you. I was trying to say the the issue could be the ammeter itself and to check it in addition to the other items that had been mentioned. In my case, the connections at the factory ammeter were clean and tight. The wiring showed no evidence of hardening or excessive heat. After I disconnected the ammeter altogether, my problem went away. I then installed an aftermarket voltmeter to monitor the electrical system. Here is another article. This one of from some guy who gave tech advice for one of the Mopar magazines for years. He also suggests that the ammeter in pre-'75 Mopars is a weak link in the electrical system. He goes on to say that Chrysler recognized this and changed to a different design in '75. Chrysler then changed to using a voltmeter instead of an ammeter altogether in the 80's. If there was nothing wrong with the original pre-'75 design, then why would they have changed it?

https://www.allpar.com/history/mopar/electrical.html
 
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The full load ammeter setup is not the weakest link really but the bulkhead. Aside ( IMHO as I have mentioned since ever ) the low rate charge alternators.

After 40 years of abuse, maybe the problem with your ammeter was the studs loosen from the internal shunt inside, which are pressed in. The heat produced due the poor electrical production made by the STOCK ALTERNATOR ( which is the first and initial guilty on this, being underrated ), stretchs out the shunt making the studs get loosen. You can fix this simply get them tight back to the shunt or even welding them to the shunt. Myself fixed a 70 Charger ammeter simply welding with lead and soldering gun. But after this you need to take care about the bulkhead conditions, upgrade accordingly, but FIRST AND PRINCIPALLY, GET A PROPPERLY RATED ALTERNATOR FOR THE CAR LOADS NEED, to get the battery out of the game as much as posible, for both situations, charge or discharge, getting all the loads playing just on alternator side of the game. This will get you an ammeter practically death centered, meaning no loading going throught. No load there no heat.

Then since 75 ( 76 on A bodies ) Chrysler allong with the rest of the automotive industry applied a new technology, using a remote reading ammeter, which doesn't get loads going throught, but just a partial and minimal load, amplified by a coil mounted on ammeter to be able to move the needle. This cars were wired way different than the full loads ammeter cars. Was just a move forward on technology, like the electronic ign and regulator systems were.

However a full load ammeter can be still safe if you understand the system, make the propper mantenience because 30, 40, 50 years are not a joke on them, specially after wiring incorrectly some extra accesories or using the incorrect battery rate but still keeping the low rated factory alternators. All of these together got an unecesary stress on them... for all these years.

Every body gets serviced their carburetors, but nobody gets serviced the electrical system. Sometimes it's handled and "tricked" up to the fail comes. Then blame the ammeter, LOL
 
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The full load ammeter setup is not the weakest link really but the bulkhead. Aside ( IMHO as I have mentioned since ever ) the low rate charge alternators.

After 40 years of abuse, maybe the problem with your ammeter was the studs loosen from the internal shunt inside, which are pressed in. The heat produced due the poor electrical production made by the STOCK ALTERNATOR ( which is the first and initial guilty on this, being underrated ), stretchs out the shunt making the studs get loosen. You can fix this simply get them tight back to the shunt or even welding them to the shunt. Myself fixed a 70 Charger ammeter simply welding with lead and soldering gun. But after this you need to take care about the bulkhead conditions, upgrade accordingly, but FIRST AND PRINCIPALLY, GET A PROPPERLY RATED ALTERNATOR FOR THE CAR LOADS NEED, to get the battery out of the game as much as posible, for both situations, charge or discharge, getting all the loads playing just on alternator side of the game. This will get you an ammeter practically death centered, meaning no loading going throught. No load there no heat.

Then since 75 ( 76 on A bodies ) Chrysler allong with the rest of the automotive industry applied a new technology, using a remote reading ammeter, which doesn't get loads going throught, but just a partial and minimal load, amplified by a coil mounted on ammeter to be able to move the needle. This cars were wired way different than the full loads ammeter cars. Was just a move forward on technology, like the electronic ign and regulator systems were.

However a full load ammeter can be still safe if you understand the system, make the propper mantenience because 30, 40, 50 years are not a joke on them, specially after wiring incorrectly some extra accesories or using the incorrect battery rate but still keeping the low rated factory alternators. All of these together got an unecesary stress on them... for all these years.

Every body gets serviced their carburetors, but nobody gets serviced the electrical system. Sometimes it's handled and "tricked" up to the fail comes. Then blame the ammeter, LOL
I agree that the bulkhead connection is a big issue. Both of the articles that I linked mention that and describe how to fix it with solid soldered connections. I did not have to go that far because all of the terminals at the bulkhead were clean and tight AND once I bypassed the ammeter, my problem went away. And believe me, all of this was done AFTER the alternator, voltage regulator, and every electrical connection that I could find was checked. In my case, the ammeter was not the first thing I checked, it was the last thing I checked. I even installed a ground strap from the engine block to the chassis. I also agree with you in saying that repairing the factory ammeter would have fixed the issue, (as opposed to replacing it altogether with a voltmeter). There are a few guys who sell new replacements ammeters with modern hardware that will work great and look completely stock. Also, they sell an upgraded model that fits in the stock location that measures voltage, not current. They both look like good options, however they are more expensive and more involved to change than an aftermarket gauge that you could mount under the dash. Also, I didn't care about a bone stock appearance. My decision to switch to a voltmeter was based on some information that I pulled off of Autometer's website. I mean they make ammeters AND voltmeters... so they don't care which one you buy. However, based on the info in the attached link, a voltmeter seems like the way to go.

https://www.autometer.com/resources/index/faq_view/id/18


(btw, you got to love these condescending little "lol's" and "let me see if I understand this's" when someone suggests something that is contrary to what you think...and without even knowing all of the details...)
 
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If there was nothing wrong with the original pre-'75 design, then why would they have changed it?
For the same primary reason auto manufactures make any production changes, to save a few cents in production costs.

If the design was so flawed, failures would have taken place much sooner, within year or two of being built. Didn’t happen, never saw any spontaneous ammeter failures at the dealer back then that wasn’t caused by previous poor repairs. Saw plenty of bulkhead connector overheats/failures, installed many factory designed bulkhead by-pass kits under recall.
 
For the same primary reason auto manufactures make any production changes, to save a few cents in production costs.

If the design was so flawed, failures would have taken place much sooner, within year or two of being built. Didn’t happen, never saw any spontaneous ammeter failures at the dealer back then that wasn’t caused by previous poor repairs. Saw plenty of bulkhead connector overheats/failures, installed many factory designed bulkhead by-pass kits under recall.
So are you suggesting that 1)Mark Hamilton, the author of the first link that I posted was wrong when he wrote that the factory ammeter could be a problem? AND 2) That Richard Erehnberg, author of the second link that I posted, tech advisor for Mopar Action magazine for many years was wrong when he stated the factory ammeter could be a problem? AND 3)That I was wrong that I concluded that my ammeter was an issue when EVERYTHING else mentioned in this thread checked out OK and my issue did not go away until I bypassed the ammeter? AND 4) That the OP of this thread shouldn't even waste his time checking his ammeter if everything else in his electrical system checks out? AND 5) While we are at it, that Autometer, engineers and manufacturers of top quality gauges is wrong when they strongly recommend a voltmeter over an ammeter????
 
Yes.
Again, every passenger car, and most trucks, built by the Chrysler Corporation, roughly from 1960 thru 1976 or so, used the same basic ammeter design, excluding the late seventies truck design. A very large number of vehicles . If it was so flawed there would have been mass failures early on, like the later truck design failed early, that didn’t happen period. Would have been seen at the dealers back then, would have been recalls, would have been well documented.

All the references you cite, contain several assumptions/statements not backed up by fact.
As I mentioned in an earlier post, after 50+ years, the ammeter connections should be checked as well as all other connections in the charging circuit that the ammeter is currently showing current fluctuations, as it was designed to do.

The notion that any automotive electrical component should last 40-50 years without any servicing or inspection, exposed to unknown levels of moisture and abuse, is mysterious to me. Especially a device designed to handle some current. If it fails after 40-50 years, it’s a flawed design?

As for aftermarket gauge manufactures today? Liability, the safe installation of any high current device requires a level of understanding and skill that most average car enthusiasts, and some professionals, do not possess these days.
 
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+1

:thumbsup:

The notion that any automotive electrical component should last 40-50 years without any servicing or inspection, exposed to unknown levels of moisture and abuse, is mysterious to me. Especially a device designed to handle some current. If it fails after 40-50 years, it’s a flawed design?

Althought some of this failures came out maybe after 20 or 25 years... depending on the car bad use and abuse. But STILL how many times on that time period ppl has serviced the carb or even changed ? but ppl blames the carb ?... or brake pads, or even rotors ?

lets beging from the begining... ANY CHARGE OR DISCHARGE READING FOR LONG TIME OR WIDE IS A BAD READING. But since ppl doesn't understand the ammeter, symply despite the reading...

one of the Causes to don't understand the ammeter comes Manufacturers, calling it ALTERNATOR gauge. Then if you see a CHARGE reading you think that is good, but IS NOT and is one of the heat and melting causes. Ammeter must be on center the most of the time as posible.

From tech bulletin:

Ammeter-zero-Master-Tech1960.png




And source accesories from batt post is simply WRONG and is something everybody has made since EVER, from "mechs" up to owners... ammeter will register it as a charge status. No need to register that which will add unnecesary stress to the system. EVERYTHING must be sourced from alt side, but of course stocks alts are NEVER ENOGH to feed those ( they weren't able to feed the stock configuration safely anyway ). Upgrade accordingly and stop blame the ammeters for the ignorance.
 
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Nacho-RT74 was a great help to me doing some unique wiring in my '63 Plymouth knows his stuff. I also had amm gauge issues and evidence of overheating at BH and gave me advice on how to bypass it; right now I still have it disconnected but have most of the suggested wiring routed for it. Other projects have kept me from finishing it. Articles I had read discussed fire hazards with the old arrangement and lots of ugly photos of the damage done. From my slant sure made it appear that amp wiring through the BH was a bad arrangement..
 
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