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71 charger 383 ammeter bypass?

How do I know? I installed a 85 amp alternator with a modern group 34 battery from a Honda accord. I left the interior dome light on while at school. The car started just fine and everything worked, so thought it's all good. Took my friend home, then heading over to another friend's house. Then poof! The ammeter went up in smoke. Took half the dash harness and most of the engine harness.

Now that I have have by-pass the ammeter, I could do the exact same thing and NOTHING would happen. ABSOLUTELY nothing.

And today, if I had the ammeter hooked up like stock, my big *** alternator would smoke the dash before I left my neighborhood.

Giving advice to keep that damn thing dangerous and careless which is why i'm so passionate about it.
 
So why don't you two go crawl back under the rocks y'all crawl out from and stay the $^@# out of conversation about upgrading people charging systems before they burn their car up listening to you? My advice would only improve the system and reduce the chance of fire.

And if you notice, Nacho is talking about keeping the exact alternator and battery specs. There is no mention about upgrading either side. There is no mention of "do this if you installed a 220 amp alternator with two big batteries." It's do this to keep your 65 amp alternator from smoking your 50 year old charging system built for a 35 amp generator.

Also, at what point will you two say is the limit of the ammeter charging system? What is that limit? 35 amp? 65 amps? 100 amps? 200 amps? 1000 amps? What is the limit? Hmmm?
 
Jeez man calm down.
And today, if I had the ammeter hooked up like stock, my big *** alternator would smoke the dash before I left my neighborhood.
This is completely false. This is why the output for the charging system is on the alternator side. It never passes through the ammeter unless charging the battery as long as your alternator can provide enough amperage for everything connected to it.

And I very much doubt that the car could start if the battery was low enough that the it would take so long to recharge the battery at high amps that the ammeter would melt. If it DID get to that point, there’s a fusible link between the battery and the ammeter from the factory to prevent this. It’d burn up first, because - if I remember correctly - it’s rated at 30 amps. Less than this 35 amp figure that you are using. Where did you get that number by the way? That’s a genuine question, I’ve never actually seen it defined anywhere.
 
And yet, you can't see the problem with adding a big alternator into a system with full load ammeter designed 50 years ago for a weak generator and small battery?

Ok, one last time on this thread then tripleblack gets the last word, I’m done here. First, I don’t promote the use of the ammeters to anyone, I do challenge miss-information about them when I see it. You want to by-pass your ammeter, do it, I don’t care. But when pushing that modification to others it should be based in and backed-up with facts and not your miss-guided assumptions and or opinions. Chrysler, and some other manufactures, used alternators with a battery ammeter since about 1960 and up thru the early eighties on some Chrysler built models. Fact is, the driving force then for the move away from the use of ammeters was the higher production costs, cutting costs, no other reason. To the individual who understands changing circuits completely, the battery ammeter can provide significantly more information about the health of the charging system in real time. More than only a volt meter or idiot light. This is the reason it was designed in to system in the first place. May be outdated now but it was ahead of it’s time then.

The fact that the ammeters seem to be difficult to understand and service, higher the costs, with changing automotive technology, more electrical demands, it is likely they would have gone away at some point anyway. 50 years later, they are only dangerous to those who fail to understand them, the effects of the passage of time, the effects adding loads to the battery will cause, and the electrical principals they were designed to monitor. As I have posted earlier, I’ve never experienced a failed ammeter on anything I’ve owned or touched in all my years. Then again, I’ve never blindly connected heavy loads to the battery on anything running a battery ammeter. Any related connections I’ve touched have been properly reassembled to avoid future issues. In some cases, I was by-passing bulkhead connectors back in the seventies. That makes me washed up? So be it.

I don’t recall posting specific info or addressing upgrading alternator capacity here but I would recommend if doing so, there are some other upgrades that need to take place as well. At a minimum running 8ga charge circuit wires, and by-passing the bulkhead connectors, with or without ammeter the charge circuit wiring should be bumped up and all quick connects remove or by-passed.

Numbers? Here are some numbers, in my shop now, two 1972 bodies (mine) and a 1970 E-body with the same basic modified Chrysler designed charging systems with the mods as follows. Optima Red top 800cca, 1000ca, 50ah. Tough stuff 130-amp Chrysler reproduction alternator, externally regulated. 8-gauge marine grade primary charge circuit wires. Alternator output is connected to the input side of an 80-amp circuit breaker mounted on the fire wall. Another 8-gauge run from that same circuit breaker stud thru the firewall to the alternator side of the ammeter where the original 12-gauge dash harness ammeter wire remains (leads to the factory load splice). Ammeter connections are properly tightened and insulators in good shape. The ammeter to battery charge wire is also 8 gauge with a 12-gauge fusible link at the starter relay. The upsized charge wires replace the original 12-gauge wires, nothing is “paralleled”.

The circuit breaker protects another 8-gauge run to the trunk and connected to a 400-watt amplifier (at 13.5 volts that’s a potential ~30-amp add-on, doing the math). A pair of 40-amp circuit breakers to protect the forward light mods are also connected to the alternator out at the circuit breaker. Running a total 560 watts Hella H1 & H4 lead lamps on relays (potential total 42 add-on amps, 30 amps hi beam, 12 amps low beam). A few other non-original loads and factory air and power windows. All loads, factory and add-on are on the alternator side of the ammeter. The MSD controller should be worth about 10-12 amps. Some other connection replacement to reduce voltage drop at the voltage regulator, Anderson PowerPole 45amp rated terminals replacing the Molex ignition switch disconnect to be specific.

Net result? Quite a bit potential total vehicle load and not a single amp of that total vehicle current load, factory and added, flows thought the ammeter when the engine is running as was originally designed. Battery charged, engine running, 130 amps of power available from the alternator, loads on, equals a centered ammeter. Won’t go into details here on the audio system, all quality components used with zero noise artifacts induced. Nothing connected directly to the battery.

Battery charge rate in excess of 15-20 amps? Not likely, never seen anything close to it with above configuration. Too many variables to debate you on this subject here but healthy batteries are limited in the charge current they draw and can accept, it’s not directly proportional the current state of charge. The use of a battery maintainer is recommended anyway, a fully charged AGM draws 200 ma.

When the name calling starts, I check out.
 
Ok, one last time on this thread then tripleblack gets the last word, I’m done here. First, I don’t promote the use of the ammeters to anyone, I do challenge miss-information about them when I see it. You want to by-pass your ammeter, do it, I don’t care. But when pushing that modification to others it should be based in and backed-up with facts and not your miss-guided assumptions and or opinions. Chrysler, and some other manufactures, used alternators with a battery ammeter since about 1960 and up thru the early eighties on some Chrysler built models. Fact is, the driving force then for the move away from the use of ammeters was the higher production costs, cutting costs, no other reason. To the individual who understands changing circuits completely, the battery ammeter can provide significantly more information about the health of the charging system in real time. More than only a volt meter or idiot light. This is the reason it was designed in to system in the first place. May be outdated now but it was ahead of it’s time then.

The fact that the ammeters seem to be difficult to understand and service, higher the costs, with changing automotive technology, more electrical demands, it is likely they would have gone away at some point anyway. 50 years later, they are only dangerous to those who fail to understand them, the effects of the passage of time, the effects adding loads to the battery will cause, and the electrical principals they were designed to monitor. As I have posted earlier, I’ve never experienced a failed ammeter on anything I’ve owned or touched in all my years. Then again, I’ve never blindly connected heavy loads to the battery on anything running a battery ammeter. Any related connections I’ve touched have been properly reassembled to avoid future issues. In some cases, I was by-passing bulkhead connectors back in the seventies. That makes me washed up? So be it.

I don’t recall posting specific info or addressing upgrading alternator capacity here but I would recommend if doing so, there are some other upgrades that need to take place as well. At a minimum running 8ga charge circuit wires, and by-passing the bulkhead connectors, with or without ammeter the charge circuit wiring should be bumped up and all quick connects remove or by-passed.

Numbers? Here are some numbers, in my shop now, two 1972 bodies (mine) and a 1970 E-body with the same basic modified Chrysler designed charging systems with the mods as follows. Optima Red top 800cca, 1000ca, 50ah. Tough stuff 130-amp Chrysler reproduction alternator, externally regulated. 8-gauge marine grade primary charge circuit wires. Alternator output is connected to the input side of an 80-amp circuit breaker mounted on the fire wall. Another 8-gauge run from that same circuit breaker stud thru the firewall to the alternator side of the ammeter where the original 12-gauge dash harness ammeter wire remains (leads to the factory load splice). Ammeter connections are properly tightened and insulators in good shape. The ammeter to battery charge wire is also 8 gauge with a 12-gauge fusible link at the starter relay. The upsized charge wires replace the original 12-gauge wires, nothing is “paralleled”.

The circuit breaker protects another 8-gauge run to the trunk and connected to a 400-watt amplifier (at 13.5 volts that’s a potential ~30-amp add-on, doing the math). A pair of 40-amp circuit breakers to protect the forward light mods are also connected to the alternator out at the circuit breaker. Running a total 560 watts Hella H1 & H4 lead lamps on relays (potential total 42 add-on amps, 30 amps hi beam, 12 amps low beam). A few other non-original loads and factory air and power windows. All loads, factory and add-on are on the alternator side of the ammeter. The MSD controller should be worth about 10-12 amps. Some other connection replacement to reduce voltage drop at the voltage regulator, Anderson PowerPole 45amp rated terminals replacing the Molex ignition switch disconnect to be specific.

Net result? Quite a bit potential total vehicle load and not a single amp of that total vehicle current load, factory and added, flows thought the ammeter when the engine is running as was originally designed. Battery charged, engine running, 130 amps of power available from the alternator, loads on, equals a centered ammeter. Won’t go into details here on the audio system, all quality components used with zero noise artifacts induced. Nothing connected directly to the battery.

Battery charge rate in excess of 15-20 amps? Not likely, never seen anything close to it with above configuration. Too many variables to debate you on this subject here but healthy batteries are limited in the charge current they draw and can accept, it’s not directly proportional the current state of charge. The use of a battery maintainer is recommended anyway, a fully charged AGM draws 200 ma.

When the name calling starts, I check out.

List all the impressive stats... Uses battery maintainer to keep batteries top off so as not to over tax the charging system.

Mofo. The system fails when it's over taxed! That's what I've been talking about the whole time. Drain one those batteries to 70% and see if the ammeter doesn't burn up.
 
Jeez man calm down.

This is completely false. This is why the output for the charging system is on the alternator side. It never passes through the ammeter unless charging the battery as long as your alternator can provide enough amperage for everything connected to it.

And I very much doubt that the car could start if the battery was low enough that the it would take so long to recharge the battery at high amps that the ammeter would melt. If it DID get to that point, there’s a fusible link between the battery and the ammeter from the factory to prevent this. It’d burn up first, because - if I remember correctly - it’s rated at 30 amps. Less than this 35 amp figure that you are using. Where did you get that number by the way? That’s a genuine question, I’ve never actually seen it defined anywhere.

I get it. Don't actually use the charging system and everything is fine. Well no ****.

Bad advice to say to leave the ammeter in the car. It's a ticking time bomb. If you have a decent size battery and that thing drains, the charging system will be over worked, and the ammeter will burn up. Prove me wrong.
 
The system fails when it's over taxed! That's what I've been talking about the whole time. Drain one those batteries to 70% and see if the ammeter doesn't burn up.
Nope, wrong again, there is no level of discharge that would create a charge current that would exceed the ammeter current capacity or any of it’s connections or upgraded wiring. The battery change rate is limited, never seen anything close the full scale charge on anything.

Really? Had to look that one up, I guess I am washed up.
 
I get it. Don't actually use the charging system and everything is fine. Well no ****.

Bad advice to say to leave the ammeter in the car. It's a ticking time bomb. If you have a decent size battery and that thing drains, the charging system will be over worked, and the ammeter will burn up. Prove me wrong.
I'm saying it would never get to the point of melting the ammeter even if a crazy amperage WAS going back across it to charge the battery (which wouldn't happen if it was wired correctly - batteries don't charge at full amperage as they fill up...). The fusible link is there to prevent that, so something else was wrong if your ammeter melted.
 
so something else was wrong if your ammeter melted.

Yes. It's called a bad and dangerous full load ammeter design that was abandoned by most car manufactures 60+ years ago and everybody else 40+ years ago. If you want to run an ammeter, use a stunt style. If you want to live in the 21st century, use a volt meter.

You know it's really something that there are folks like you that wants to argue the virtues of a design that was proven dangerous many many years ago. It's like arguing with a Flat Earther; are they truly genuine or just playing dumb?
 
“stunt”? do you mean an external shunt type ammeter?

“design that was proven dangerous many many years ago”?

Interesting, proven by who and when did that happen, do you have published results somewhere to back up this false claim?

How about we look at some statistics? Virtually every production motor vehicle Chrysler Motors made since 1960, and roughly through the late seventies, ran an alternator and battery ammeter. A very large number of vehicles, with such a “ticking bomb” design flaw, as you describe, you would think, statistically, that all those vehicles would have burned up within a few years. Just think of all the dead and failed batteries, and other electrical problems that would have over-stressed the charging systems of all those vehicles. But that didn’t happen did it? Never really saw any ammeter or factory-made ammeter connection issues at the dealers until the plastic Dodge truck ammeters of the late seventies. Did see a lot of melted bulkhead connectors early on after Chrysler moved to the Packard 56 terminals in the charge circuit, should have stuck to the screw connections of the early sixty’s bulkhead charge circuit pass-through. Performed numerous recalls relating the bulkhead connectors but absolutely zero wide-spread design or stress related ammeter issues. If there had been, there would be an extensive paper trail of TSB’s and recalls about failing ammeters. The passenger car ammeters are robustly built and can handle a very large amount of current when well maintained and with properly maintained connections. Some Police car ammeters were factory scaled to 60 amps or better, see the wiring diagram on post #28.

I’ve taken apart all stock, well maintained/garaged, un-touched electrical, daily driver Mopars, 40-45 years after production, having an ammeter that looked and worked like new, not a hint of current stress.

Curious, if you believe the design is such a “ticking time bomb”, why did your ‘73 ammeter wait 22 years, after being built, to spontaneously combust in ’95 after coming into your possession. A couple amps in trunk maybe, wired to the battery? On a vehicle with an ammeter between the battery on the alternator? That would explain it, wouldn’t it?

You’ve posted a great deal of mis-information here to back up your mis-guided opinion on this matter. Several of your statements have been directly proven here to be wrong. You then revert to name calling when some others here with clearly more experience and/or knowledge on the subject continue challenging your inaccurate and false statements.
 
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Yes. It's called a bad and dangerous full load ammeter design that was abandoned by most car manufactures 60+ years ago and everybody else 40+ years ago. If you want to run an ammeter, use a stunt style. If you want to live in the 21st century, use a volt meter.

You know it's really something that there are folks like you that wants to argue the virtues of a design that was proven dangerous many many years ago. It's like arguing with a Flat Earther; are they truly genuine or just playing dumb?
I'm done here if you're just gonna keep calling me names because you disagree.
 
I'm done here if you're just gonna keep calling me names because you disagree.

I didn't call you a name. I compared you to a flat Earther because I seriously don't know if you're genuine. Based on what you have said, how could I? Look, almost everyone I ever talked to has had some sort of issues ammeters, except for you two. You two act like it's the best thing since sliced bread and can't figure out why modern cars don't have them. You want to act like people like me who have had issue with them (burning up in '95 and another one running hot from 2016-2018) are completely wrong to warn others. You two act like we live in a prefect world. You two act like there has never been a single catastrophic failure ever with an ammeter. You two ignore the fact that a 800 cca battery at 80% will present enough a voltage differential to burn an ammeter up. You two both ignores the issue of the ammeter by saying there's never a problem if you don't use it, aka: always use a fully charged battery topped off with a battery maintainer. That like saying a roof won't leak if doesn't rain. As in, if an ammeter never carry current, it will never heat up and burn out. Well, no ****. I'm really happy you two just love your ammeter and want to keep them. Me, I have had nothing but problems with them.

There's more than enough evidence out there by the simple fact NO MODERN CAR USE THEM ANYMORE that there's an major issue with them. What is that issue? They heat up and burn out, and take the dash harness with them.

I've only seen this level of ignoring facts with flat eather and people intentionally trying to mislead other. So which is it?
 
Went to Advance Auto today. Couldn't find an ammeter in the "performance section." Asked the dude behind the counter. He looked at me like I was crazy, then said "Why would you want that? Do you want to burn your car up?"

Exactly.
 
Went to Advance Auto today. Couldn't find an ammeter in the "performance section." Asked the dude behind the counter. He looked at me like I was crazy, then said "Why would you want that? Do you want to burn your car up?"

Exactly.
Are you serious? That’s your back-up for all the BS you’ve posted? The guy behind the counter at the local parts store? We all know about the vast wealth of classic car knowledge and experience that can be had from the kid behind the counter at the corner parts store these days. Know, ask him to explain the inner workings of a carburetor. Try this, ask him for a matched set of v-belts for factory AC compressor/alternator/crank. I was never able to find anyone at those stores lately that knew what a matched set was. At least this explains where some of your mis-information is coming from.

Maybe it’s time you start yet another thread over in the electrical section about your take on the “ticking time bomb ammeter” bs. This thread’s been hijacked enough, is now way off topic.
 
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LOL! I was pointing out they had all kind of volt meters, but no ammeter.

Hey, so I figure I'm using 160 amps when I turn the car on before the engine is started. Do you think that is enough to blow the ammeter if I were to listen to your antiquated advice? I think I might burn my old ammeter just to see. I expect it to get REALLY hot before it smokes. Should be fun.
 
Hey, so I figure I'm using 160 amps when I turn the car on before the engine is started. Do you think that is enough to blow the ammeter if I were to listen to your antiquated advice? I think I might burn my old ammeter just to see. I expect it to get REALLY hot before it smokes. Should be fun.

Replied on a new thread
 
JESUS, can we give this up? I'm sure this thread has been beaten to death!!!!!!!!!!!!!!!!!!!!
 
JESUS, can we give this up? I'm sure this thread has been beaten to death!!!!!!!!!!!!!!!!!!!!

Not dead enough. As long as people suggest keeping an ammeter, I will keep telling the world why Ma-Mopar charging system is an awful design and why wiring the alternator directly to the battery is a much better and safer solution.
 
Not dead enough. As long as people suggest keeping an ammeter, I will keep telling the world why Ma-Mopar charging system is an awful design and why wiring the alternator directly to the battery is a much better and safer solution.

Well, you've made the point clear about the charging system. With that said, you should drop it now. Just like any other topic here, all we can do is give advice etc. If no one wants to listen, so be it. Like the old saying goes " you can lead a horse to water but you cant make them drink"
 
Well, you've made the point clear about the charging system. With that said, you should drop it now. Just like any other topic here, all we can do is give advice etc. If no one wants to listen, so be it. Like the old saying goes " you can lead a horse to water but you cant make them drink"

If some of that “advise” is dead wrong and you are backing it up with easily disproven false and mis-leading statements that indicate you don’t have a full understanding of what you are talking about, as is the case here, don’t be surprised if the so-called advice is challenged with facts.

Like that other old saying goes “you can lead a horse to what you believe is water, turns out its really a latrine, don’t be surprised if the horse doesn’t drink”
 
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