Here is your problem. You condemned the Hemmings article as being non-factual. While it is completely true. I started to work in a Mopar dealership in 1972. Starting as a prep boy, mechanic, general parts and service director, and owner. So I have seen these failures by the 100's. Not all as bad damage wise and we learned a lot of fixes for them. The manufacturer learned as well. I stand with the article as being true and I stand by what I would recommend. You are allowed to have your opinion as well as everyone else. You are the one that started this topic expecting a debate. You need to go back and reread that article very slowly. It clearly expands on other aspects of the failing system as well as the ammeter.
Ok, one more, a little more drama, and some pissing of my own.
Now that’s interesting, I too, started my professional automotive career working my way up through the ranks at various large and small Chrysler dealers in the mid-seventies. Starting on the lube rack, PDI, parts, then master certified line tech before moving on to other brand dealers and owning/operating a high-end car stereo business, designing and installing high-end audio systems and accessories into high-end vehicles of all types. Far different experience at the Chrysler dealers back then it would appear, never saw one unexplained ammeter or ammeter connection failure until the failed attempt to construct them using plastic frames in the later seventies’ trucks. Delt with tons of bulkhead, ignition switch Molex, and single Molex engine harness disconnects in the charge output failures very early on. Preformed countless C-body recalls adding a parallel wire run around the bulkhead charge output Packard connection, alternator output stud to fuse box. Have read many internal Chrysler docs, TSBs, and such, back then and over the years, if the issue is as you have described here, would think there would have been a rather large paper trail of some kind created to back that up.
As for the explained ammeter connection failures I saw back then. comebacks, most all electrical comebacks of others always seemed to be routed my way, being raised by an EE, even then, electrical was never the mystery others made it out to be. Some other tech would leave the nuts loose or crank them down so tight it would crush the insulators during some previous dash service. Never saw any issues with connections that were untouched from the factory and had no added aftermarket loads connected directly at the battery.
By far, most explained charge system connection failures were caused by added accessories at the battery. Until Chrysler beefed up the fleet/police production charging systems (including by-passing the bulkhead connectors), most failures I saw were police cars shortly after all their radios/lights were installed.
So-called article “facts”, as pertaining to a completely stock healthy well maintained ’60-‘70s Chrysler passenger car charging system as originally designed and while the vehicle is in normal operation, no modifications.
“the fact that all system current has to flow through the ammeter for it to work”
Misleading at best, the ammeter does not require any current to “work”. Only battery charging/discharging current should be flowing through the ammeter while the vehicle is in operation, regardless of load demand. The only conditions the ammeter will register “full system current” is when the vehicle is not in use, should be no system current flowing at that time, or key on and engine not running. Once more, the stock ammeter can more than handle the stock system loads without alternator output.
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As the wiring ages, its electrical resistance increases”
Not factual, the electrical properties of a given conductor will not simply change over time. Corrosion, oxidation at terminals because of excessive over-exposure to moisture, over time causes resistance build up. Insulation break-down is due to excessive heat and/or ultra-violet light over exposure, general abuse, not simply due to age. There is plenty of well-preserved original 50+ year-old wiring in good condition safely in use today.
“As the output of the alternator increases, so does the amount of current going through the ammeter”
Absolutely not factual, again only battery charge/discharge current should flow through the ammeter while in operation. Healthy fully charged battery, that is almost 0 amps of current. All factory loads are on the alternator side of the ammeter at splice 1, or some cases, directly connected to the alternator ammeter stud. As the vehicle/system loads vary, the alternator output increases/decreases to cover the demand, all on the alternator side of the ammeter, this vehicle /system current does not flow through the ammeter at all on a healthy stock Chrysler charging system. All vehicle loads are to be on the alternator side of the ammeter originally as designed. Any loads on the battery side of the ammeter will source its power needs from the alternator through the ammeter and related connections because the alternator is the main power source when in operation, not the battery. This added current at the battery is registered as false charging current on ammeter and puts the ammeter and related connections well outside of its original design limits.
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Both create additional heat, often in the workings of the ammeter. It also doesn't help when carmakers use shunts to tune the ammeters, adding even more heat right at the gauge”
Again, not factual, shunts to tune ammeters? There are no shunts or shunt resistors, or any other heat generating components/devices, that will add “more heat”, within a Chrysler passenger car ammeter from this era, flat out wrong. Any heat damage at the ammeter is a result of excessive resistance at the ammeter studs likely cause by excessive current or abuse. There are no “workings” in the ammeter, simple solid brass buss, a permanent magnet. Needle responds to changes in the magnetic field as influenced by current flow though the buss.
Strange the supporting pictures in this article show a pristine mint condition ammeter/ammeter connections that supposedly left this Road Runner stranded. No sign of any previous or current high resistance heat damage of any kind at those terminals. There is no way that the pictured ammeter left any vehicle stranded, leaving the article lead-in premise completely in doubt. Kind of hard to believe that the pictured rather rare mint condition Rallye cluster ammeter was sacrificed/cut up for a cheap voltmeter substitution based on the stated mis-facts.
Further on the article, it directly conflates the later plastic framed truck ammeters failures with the original earlier passenger car construction, makes no sense whatsoever. At lease the Mad Electrical article specifically describes their remedy as targeting the later truck plastic framed ammeter melting failures. It appears it is some readers of that article that conflate the two completely different ammeter designs.
These original passenger car ammeters from this time do not simply “give up the ghost” or “spontaneously combust” for no reason whatsoever. You want to modify your electrical system to what you believe will better handle modern accessories/loads, not comfortable with or simply don’t like the higher current potential in the dash or simply because that’s how it’s done today. I get it, go for it. If you are going to write an article, or post on a forum, to promote your modification, at least get your facts straight.