Dubjitsu
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I'm looking at swapping out my 60amp alternator (69 coronet) to a 75 or 100 amp. Is this just simply pull the other one out and plug the new one in or are there other things I need to know before doing this? Thx
Upgrading the Alternator, anything I need to know?
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69a100
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themechanic
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Bypass the ammeter (install a voltmeter optional), replace the output wire from the alt to the batt with thicker wire, install headlight relay harness.
My opinions may be a bit different:
1. I changed my charger maybe 25 years ago to a newer style 70 amp alternator with a solid state chrysler regulator with no other changes.
2. If you have not added any big current consumers, you have a good fully charged battery and the car starts well...
then even the larger alternator it will not need to produce a large amount of current. So the existing wire size, ammeter connection etc is fine.
Living in the northeast where it is not so hot likely helps with the longevity of the wiring.
I like having the original ammeter, just reconnected the one in my Plymouth that someone bypassed before I bought the car.
The firewall bulkhead connector is always the weak point I think.
A newer style permanent magnet starter is also a good upgrade for hot starts and extends battery life.
1. I changed my charger maybe 25 years ago to a newer style 70 amp alternator with a solid state chrysler regulator with no other changes.
2. If you have not added any big current consumers, you have a good fully charged battery and the car starts well...
then even the larger alternator it will not need to produce a large amount of current. So the existing wire size, ammeter connection etc is fine.
Living in the northeast where it is not so hot likely helps with the longevity of the wiring.
I like having the original ammeter, just reconnected the one in my Plymouth that someone bypassed before I bought the car.
The firewall bulkhead connector is always the weak point I think.
A newer style permanent magnet starter is also a good upgrade for hot starts and extends battery life.
Dubjitsu
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I bought the car with a blue tooth radio in it and I added a vintage air system and ever since then have been having electrical issues. Not sure what happened, but thought possibly the alternator needed an upgrade
The regulators can get sticky points, and it's possible to blow a diode in the alternator making it a half wave rectifier. These would be the two common failures in the original system. If it's just a regular stereo not a big power add. I don't know much about the vintage air? It's a compressor based AC system?
Nacho-RT74
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Dubjitsu
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Yes, compressor.
oldbee
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Just the same load as running the heater in winter. Kinda agree with “nat” aabout adding a bypass though.
Crackedback
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Run a protected charge wire from the alternator to starter relay, bypass ammeter and leave all the other wiring in place if in good shape. Use a voltmeter to monitor the system.
I'm not a fan of the mad approach. Prefer to not mess with any of the factory wiring.
The ammeter and bulkhead are consistently bad spots for failure in these old cars. Ammeters grounding into the cluster case happens a lot.
I make charge wires with fusible links installed to run from Alt to Starter relay and plug and play headlight relay kits for our cars. Let me know if you are interested.
I'm not a fan of the mad approach. Prefer to not mess with any of the factory wiring.
The ammeter and bulkhead are consistently bad spots for failure in these old cars. Ammeters grounding into the cluster case happens a lot.
I make charge wires with fusible links installed to run from Alt to Starter relay and plug and play headlight relay kits for our cars. Let me know if you are interested.
Nacho-RT74
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also, in other words:
http://www.heritech.org/cuda/Charge.html
understand how it works the system first, then choose the best suit for you.
Most of the "FIXES" floating on this kind of threads comes from the unknowledgement and fears. beat the fear with knowledgement
Crackedback
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I always enjoy the running down of people that have seen ammeter failures and the damage they do. It is not from "fear" that I remove them, it's from damage caused by the failure. We simply aren't "smart" enough to get it. 
Same as people running an always live hot charge wire from front to rear when installing a trunk mount battery. There's no potential issues doing that either, right?
EVERYTHING is subject to failure.
As I say, "Pick you parts, Pay your money!"
Lots of way to skin a cat in this deal, some are safer than others.
Same as people running an always live hot charge wire from front to rear when installing a trunk mount battery. There's no potential issues doing that either, right?
EVERYTHING is subject to failure.
As I say, "Pick you parts, Pay your money!"
Lots of way to skin a cat in this deal, some are safer than others.
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Are you implying then an ammeter (from this era) with properly maintained connections and intact insulators will spontaneously combust on its own? I’ve seen many heat damaged ammeters, not a one correctly installed with tight, clean connections and intact insulators. Plenty of other weaknesses in these 50+ year old charging systems to improve before condemning a functional ammeter.
Crackedback
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Problem is, the systems are quite commonly not maintained well. I prefer to not have an active ammeter in ANY car I own. The mopar charging system is a poor design from an efficiency standpoint. Yes, I've seen an internal ammeter failure.
IMO, ammeters are ridiculous in a car when there are other, safer methods to monitor the charging system. Manufacturers figured this out many years ago from a cost and safety approach.
Pick your desired approach and go with it.
Nacho-RT74
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Well I have my car with stock ammeter, a parallel wiring to the bulkhead and 78 amps alt since maybe 10 years and is perfect. The amm barelly gets readings. no readings, no heat. Maybe I'm wrong and my car should burnt quite ago. Something is wrong on my car then.
( must to say my car was driver untill got disassembled for a body job, with A/C )
( must to say my car was driver untill got disassembled for a body job, with A/C )
Crackedback
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That's great, until it's not. Your car, your approach. Simple as that.
To deny that there are issues that arise from ammeters and charge wiring in these cars is folly. Carry on.
To deny that there are issues that arise from ammeters and charge wiring in these cars is folly. Carry on.
Nacho-RT74
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the problem is the poor alt capacity at iddle and the bulkhead terminals weakness, not the ammeter itself. Save that and you'll be safe still with the amm.
sometimes even the bulkhead will be able to hold the load, depending on car equipment.
If just Chryco was get a correct alt capacity on our cars since the begining, maybe 70% of the cars damaged on this topic were safe.
Let's try to understand and accept this... as far the batt is out of the play providing power, the ammeter will be out of the play too on same propportion. And the only way to get this is an alt able to provide all the juice the car will need at any speed.
sometimes even the bulkhead will be able to hold the load, depending on car equipment.
If just Chryco was get a correct alt capacity on our cars since the begining, maybe 70% of the cars damaged on this topic were safe.
Let's try to understand and accept this... as far the batt is out of the play providing power, the ammeter will be out of the play too on same propportion. And the only way to get this is an alt able to provide all the juice the car will need at any speed.
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Crackedback
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Condescend much? Let's try to understand and accept?
It's not smart to run the charge system through the bulkhead (twice) and the ammeter. That's a bad design from the start. A weak alternator has little to do with a substandard wiring approach.
Yes, the alternator "hopefully" powers the car when the engine is running.
Pick your approach and go with it.
It's not smart to run the charge system through the bulkhead (twice) and the ammeter. That's a bad design from the start. A weak alternator has little to do with a substandard wiring approach.
Yes, the alternator "hopefully" powers the car when the engine is running.
Pick your approach and go with it.
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