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For the voltmeter conversion crowd

Having various in-depth chats with Nacho, and some experience on my end (not near what he has) I rank this guy high up there on knowledge. This topic can be found on the forum; likely hundreds of posts, some are mine; more questions than answers, lol. The amp gauge discussion and my reading on it, was not good design running the wires through the BH. Of course, what vehicle mfg designs their products to last multiple decades. I got a good glance viewing my skanked BH I replaced much later than I should have. Meanwhile was coached by Nacho on safer ways to run/connect the amp gauge wires, being kind enough to do so, bypassing the BH. Too bad that this particular routing (bypassing the BH) was only done on special vehicles like police cars as was the case with my ride.
 
pnora said:
So when you are all done the ammeter is doing little to nothing. Wiring all loads to the alternator stud is not correctly wiring the system. This bull crap of running loads off the alternator stud is just wrong for many reasons. The loads should be directly pulled from the source. The battery. The alternator then just has to do its job. Wiring the alternator directly to the battery is the best and safest way. Then using the voltmeter to monitor it.
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“The loads should be directly pulled from the source.” I agree 100%, problem with this post however, unless you are working on a Tesla, the alternator, not the battery, is the primary source of power while the vehicle is in operation on this planet. Running an ammeter, any loads connected to the battery is added current stress for the ammeter and related connections. Guess what happens then, connections, insulators can fail at the ammeter.

Not running an ammeter, no matter.
 
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72RoadrunnerGTX said:
“The loads should be directly pulled from the source.” I agree 100%, problem with this post however, unless you are working on a Tesla, the alternator, not the battery, is the primary source of power while the vehicle is in operation on this planet. Running an ammeter, anything loads connected to the battery is added current stress for the ammeter and related connections. Guess what happens then, connections, insulators can fail at the ammeter.

Not running an ammeter, no matter.
Click to expand...
Not sure what your getting at here. Are you saying loads should be sourced off the alternator terminal??
 
The correct source on a car riding around is the alt, not the batt.

The batt is the source just with engine off. And a reserve power source when riding around.
 
RJRENTON said:
ONCE AGAIN, an EXCELLENT dissertation and explanation, especially the reference to the "idiot lamp". Its somewhat humorous, at least to me, that the persons professing no or limited knowledge of electrical systems ( #s 10, 13,14), seem to profess a complete understanding of the issue. If one wants to utilize an ammeter to monitor the charging system current...great....likewise, if one wants to use a volt meter to monitor system voltage (not current flow) as the two components (voltage / current) are somewhat mutually exclusive but related.....also great.
This subject is approaching the 50th iteration.....surely, there cannot be any more "my way vs your way" variations left to discuss....but, maybe not.... BTW....EFI systems are not typical high current consumers nor are the fuel pressure pumps, it's usually the added electrical requirements of the cooling system fans. Just my opinion of course.
BOB RENTON
Click to expand...

Have you ever noticed 72RoadrunnerGTX and me are on same position about this subject?

Damn! You are definitelly obsessed!
 
Nacho-RT74 said:
Have you ever noticed 72RoadrunnerGTX and me are on same position about this subject?

Damn! You are definitelly obsessed!
Click to expand...
Probably because RJRENTON has forgot more than the pair of you will ever know.
 
Nacho-RT74 said:
The correct source on a car riding around is the alt, not the batt.

The batt is the source just with engine off. And a reserve power source when riding around.
Click to expand...
Right. But you do not source load direct from the alternator stud as you instruct. The correct way is a multi circuit fused power distribution panel close to the battery. Battery directly feeds the panel. Then you wire the alternator with a large enough gauge wire direct to the distribution panel.
 
pnora said:
Right. But you do not source load direct from the alternator stud as you instruct. The correct way is a multi circuit fused power distribution panel close to the battery. Battery directly feeds the panel. Then you wire the alternator with a large enough gauge wire direct to the distribution panel.
Click to expand...
pnora said:
Not sure what your getting at here. Are you saying loads should be sourced off the alternator terminal??
Click to expand...
To be clear, the intended subject of this thread has nothing to do with a complete redesign of a vehicle’s electrical system based on one person’s opinion, having nothing to do with the original charging system design, apples and oranges. It was not about promoting voltmeters over ammeters, or vise-versa. Simply the repeated published articles promoting this conversion in a somewhat public forums while backing up, in part, the need for such a conversion by using false or mis-leading, factually incorrect statements about the original design and/or function of the ammeter within the original design.
Nothing about all the external factors more likely to have caused connection failures at the ammeter after 50+ years, or how all those years with the bolt-on accessories connected to the battery over-stressed the ammeter and related connections/wiring well beyond their design limits, because the alternator is the power source for all vehicle loads while in operation, not the battery, ammeter or not.



Frankly, the hostility posted here by those who appear to agree with the incorrect statements of facts, then post more incorrect statements of fact, surprises me a bit. Then comes the childish pissing match ****, who knows more than who, so in so “doesn’t know what he’s talking about”. Had planned respond to your inquiry from post #23 in more detail but it may be time now for a break from this thread.
 
72RoadrunnerGTX said:
To be clear, the intended subject of this thread has nothing to do with a complete redesign of a vehicle’s electrical system based on one person’s opinion, having nothing to do with the original charging system design, apples and oranges. It was not about promoting voltmeters over ammeters, or vise-versa. Simply the repeated published articles promoting this conversion in a somewhat public forums while backing up, in part, the need for such a conversion by using false or mis-leading, factually incorrect statements about the original design and/or function of the ammeter within the original design.
Nothing about all the external factors more likely to have caused connection failures at the ammeter after 50+ years, or how all those years with the bolt-on accessories connected to the battery over-stressed the ammeter and related connections/wiring well beyond their design limits, because the alternator is the power source for all vehicle loads while in operation, not the battery, ammeter or not.



Frankly, the hostility posted here by those who appear to agree with the incorrect statements of facts, then post more incorrect statements of fact, surprises me a bit. Then comes the childish pissing match ****, who knows more than who, so in so “doesn’t know what he’s talking about”. Had planned respond to your inquiry from post #23 in more detail but it may be time now for a break from this thread.
Click to expand...
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.
 
Ammeters don't really need any "maintenance" to speak of, and most old Chrysler ammeters are actually very sturdy units that can handle quite a bit of current. In my opinion, the problem with our old cars is not the ammeters, but more so the design of the bulkhead connectors and the wiring size. Neither were designed for large additional loads since our old cars, when originally built, had 35 amp alternators and few electrical loads.

Adding all kinds of things like powerful stereos, fuel pumps, electric fans, etc. require redesigning the system to work properly. Many people don't understand and don't respect the need for a well designed electrical system. Slapping a big alternator on a car to handle large loads is a recipe for disaster, and then fires caused by that are often blamed on the "Ammeter".

A car can be made to run well and safely with an ammeter (I chose to redesign my system with a voltage gauge, and that's fine too). Regardless, if you are going to add electrical loads to an old car, be sure you truly understand what you are doing.

shCarFirePICS-ml-051817-ph4.jpg
 
HawkRod said:
Ammeters don't really need any "maintenance" to speak of, and most old Chrysler ammeters are actually very sturdy units that can handle quite a bit of current. In my opinion, the problem with our old cars is not the ammeters, but more so the design of the bulkhead connectors and the wiring size. Neither were designed for large additional loads since our old cars, when originally built, had 35 amp alternators and few electrical loads.

Adding all kinds of things like powerful stereos, fuel pumps, electric fans, etc. require redesigning the system to work properly. Many people don't understand and don't respect the need for a well designed electrical system. Slapping a big alternator on a car to handle large loads is a recipe for disaster, and then fires caused by that are often blamed on the "Ammeter".

A car can be made to run well and safely with an ammeter (I chose to redesign my system with a voltage gauge, and that's fine too). Regardless, if you are going to add electrical loads to an old car, be sure you truly understand what you are doing.

View attachment 1176260
Click to expand...
With the most important aspect being: if you are going to add electrical loads to an old car, be sure you truly understand what you are doing. AMEN.....
BOB RENTON
 
pnora said:
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.
Click to expand...
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.

“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.

“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.
Ammeter.png



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.
 
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pnora said:
Right. But you do not source load direct from the alternator stud as you instruct. The correct way is a multi circuit fused power distribution panel close to the battery. Battery directly feeds the panel. Then you wire the alternator with a large enough gauge wire direct to the distribution panel.
Click to expand...

Incorrect with ammeter. All loads must be on alt side of ammeter. No matter where... straight at ammeter stud, on a splice or junction between ammeter and alt, or straight to the ammeter stud.

If you track the wiring, will notice the MAIN splice is between alt and ammeter. So is the same than sourcing straight to the alt stud.

Then after decide where to take the power, decide which section of the wire will upgrade for a bigger gauge wire... of not the full line, to feed the extras.
 
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Nacho-RT74 said:
Incorrect with ammeter. All loads must be on alt side of ammeter. No matter where... straight at ammeter stud, on a splice or junction between ammeter and alt, or straight to the ammeter stud.

If you track the wiring, will notice the MAIN splice is between alt and ammeter. So is the same than sourcing straight to the alt stud.

Then after decide where to take the power, devide which section of the wire will upgrade for a bigger gauge wire... of not the full line, to feed the extras.
Click to expand...
So when the alternator fails and you have loads on that stud what happens then.
 
The battery will feed and ammeter will show discharge AS MUST BE per factory design.

And what you do when you have an oil pump failure and gauge shows you 0 pressure?
 
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72RoadrunnerGTX said:
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 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.
You sure like to turn and twist things to back your argument. Fact the old ammeter systems were problematic period. Why do you think they were not used anymore. Problems.

“the fact that all system current has to flow through the ammeter for it to work”

Misleading, 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.

“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 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.

“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 resisters, 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.


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 of 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.
Click to expand...
 
RJRENTON said:
With the most important aspect being: if you are going to add electrical loads to an old car, be sure you truly understand what you are doing. AMEN.....
BOB RENTON
Click to expand...



I made it back on 2007. Working without fails after that with a higher output alt. Happier system than ever. No dimming lights ( Halogens sealed beams with relays ), no nothing. Everthing sourced straight from ammeter stud after the correct upgrades on stock system.

Amm showing zero reading 85-90% of the time

But since I don't know ( either 72RoadrunnerGTX ) what we are doing per your statements and my own personal experiences about this won't matter to you, we are loosing the time. Untill you try it by yourself.
 
Nacho-RT74 said:
The battery will feed and ammeter will show discharge AS MUST BE per factory design.

And what you do when you have an oil pump failue and gauge shows you 0 pressure?
Click to expand...
Bull crap All those stud loads will be pulled off the battery. Unless you have an upgraded wiring and weak links removed something has to give.
 
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