Diagnosis MOPAR Charging System

[BLK 68 R/T]

I do every day asshole, instead of belittling them!

I’m here to learn and help others when I can

There’s always something new that can be learned.

 

[ynst]

A one-wire alternator bypasses everything and requires a volt meter because the factory ammeter cannot handle the current and would turn itself into a fuse and you’d be left without any electricity to run the vehicle once you shut off the engine.

Because the vehicle electric system is connected to the alternator side of the blown out ammeter, you won’t have any juice to re-engage the starter so you really need to do a major rework to the electrical system to get power back to the fuse box.

The simplest way is to move the wire on the battery side of the ammeter over to the other post and, thus, eliminate the ammeter but, now, there’s no way to measure the alternator output.

So, now, you need to install a voltmeter.

But, since everything goes through the bulkhead connection and that’s all corroded, you still have electrical gremlins that will require attention.

A one-wire alternator is just a patch and not a solution.

Fix the real problem and, unless you need the high output alternator to run non-standard cooling fans, stick with the wiring ChryCo designed for the vehicle.

 

[Crackedback]

The stock path is a trash can as designed from the start.

How you decide to fix it is up to you. Run the ammeter or not, pick your approach and do it wisely.

 

[72RoadrunnerGTX]

A one-wire alternator bypasses everything and requires a volt meter because the factory ammeter cannot handle the current and would turn itself into a fuse and you’d be left without any electricity to run the vehicle once you shut off the engine.

Because the vehicle electric system is connected to the alternator side of the blown out ammeter, you won’t have any juice to re-engage the starter so you really need to do a major rework to the electrical system to get power back to the fuse box.

The simplest way is to move the wire on the battery side of the ammeter over to the other post and, thus, eliminate the ammeter but, now, there’s no way to measure the alternator output.

So, now, you need to install a voltmeter.

But, since everything goes through the bulkhead connection and that’s all corroded, you still have electrical gremlins that will require attention.

A one-wire alternator is just a patch and not a solution.

Fix the real problem and, unless you need the high output alternator to run non-standard cooling fans, stick with the wiring ChryCo designed for the vehicle.

Not following, what does a one-wire alternator have to do with the shunt wire bypass discussion here? Where would all the current come from that supposedly would kill (open) the ammeter when a one-wire alternator is installed? Ammeters are not measuring alternator output, should only be monitoring battery charge/discharge current, nothing to do with alternator output capacity.

 

[72RoadrunnerGTX]

The stock path is a trash can as designed from the start.

And yet seemingly countless Chrysler products came and went running this same basic charging system for a couple of decades. The vast majority had no issues at all when left alone, well maintained, no misplaced loading, and otherwise operated within its design limits. It served its original purpose. No fibbing.

 

[ynst]

The one wire between the alternator and the battery is nothing but a shunt around the ammeter.

That’s why Powermaster says it’s just fine.

It ain’t “just fine”. It’s a work-around for keeping the battery charged but it does nothing to remedy bad bulkhead connections and those marginal connections in your bulkhead connectors are where the voltage goes INTO the fuse box, headlight switch, ignition switch, etc.

 

[ynst]

Not following, what does a one-wire alternator have to do with the shunt wire bypass discussion here? Where would all the current come from that supposedly would kill (open) the ammeter when a one-wire alternator is installed? Ammeters are not measuring alternator output, should only be monitoring battery charge/discharge current, nothing to do with alternator output capacity.

If you connect a high output alternator to the factory wiring, you’ll blow out the ammeter so Powermaster bypasses the factory system with a shunt ( their one-wire) that STILL doesn’t address the real issue of bad firewall connections.

 

[ynst]

If you connect a high output alternator to the factory wiring, you’ll blow out the ammeter so Powermaster bypasses the factory system with a shunt ( their one-wire) that STILL doesn’t address the real issue of bad firewall connections.

And THAT’S why they say that there’s nothing wrong with a shunt.

 

[BLK 68 R/T]

And yet seemingly countless Chrysler products came and went running this same basic charging system for a couple of decades. The vast majority had no issues at all when left alone, well maintained, no misplaced loading, and otherwise operated within its design limits. It served its original purpose. No fibbing.

When left alone and well maintained…therein lies the problem that a lot of people have. 50+year old wiring harnesses with unknown corroded or partially broken wires coupled with aftermarket stereos, amplifiers, electric fans, fuel pumps, and the list goes on… The more loads placed on the factory system with a compromised (corroded) bulkhead connector or partially broken wires leads to higher resistance. Higher resistance leads to heat and heat is not good in this specific situation.

 

[72RoadrunnerGTX]

The one wire between the alternator and the battery is nothing but a shunt around the ammeter.

That’s why Powermaster says it’s just fine.

It ain’t “just fine”. It’s a work-around for keeping the battery charged but it does nothing to remedy bad bulkhead connections and those marginal connections in your bulkhead connectors are where the voltage goes INTO the fuse box, headlight switch, ignition switch, etc.

OK, it appears you are referring to the discussed “shunt wire” bypass as a “one wire alternator bypass”? A bit confusing with a one-wire alternator. However, it not only bypasses the ammeter, it bypasses the entire stock charge path, disables the intended function of the ammeter, and most significantly, it circumvents the circuit protection for the entire stock unfused wiring, exposes all stock wiring to very high battery sourced current levels in the event of a short anywhere.

 

[72RoadrunnerGTX]

If you connect a high output alternator to the factory wiring, you’ll blow out the ammeter so Powermaster bypasses the factory system with a shunt ( their one-wire) that STILL doesn’t address the real issue of bad firewall connections.

Just to be clear, simply swapping in a high output alternator in place of the stock rated alternator on an all-stock charging system, no changes to loading, isn’t going to blow out the ammeter. There will be no increase in current flowing through ammeter just because the alternator capacity increases.

 

[ynst]

The Powermaster alternator is a shunt system with a (recommended) fusible link.

It bypasses the factory charging system altogether, however, it does not eliminate the factory fusible link on the starter relay from where the power to the inside of the vehicle is derived so the factory protection is still there.

THIS is why Powermaster says that there's nothing wrong with a "shunt" wire. Theirs is a shunt system, therefore, there's no problem with a shunt. That's NOT the case in any situations except with their one-wire alternator systems.

This is also NOT the case with a ChryCo charging system, however UNLESS you make the a fore-mentioned modifications to the ammeter but it's only a patch to help maintain proper voltage levels at the battery.

If you try and bypass a factory MoPar alternator in the same fashion, the same original fusible link on the starter relay will protect the body harness but the alternator output will NOT be protected unless you add an additional fusible link in your shunt wire but that's still not going to cure your problem.

The reference voltage for your voltage regulator comes off the ignition circuit and if you have faulty bulkhead connections, that reference voltage will be incorrect and your charging system will STILL be screwed up.

The fix, as has been mentioned before, is to repair/replace the bulkhead connections, not a kludge shunt bypass, and THAT will solve your problems, .

 

[ynst]

Just to be clear, simply swapping in a high output alternator in place of the stock rated alternator on an all-stock charging system, no changes to loading, isn’t going to blow out the ammeter. There will be no increase in current flowing through ammeter just because the alternator capacity increases.

UNLESS the battery's flat and the engine's running at high idle after start-up which will put the alternator output close to maximum as it tries to charge the dead battery. It WILL fry the factory ammeter.

 

[72RoadrunnerGTX]

UNLESS the battery's flat and the engine's running at high idle after start-up which will put the alternator output close to maximum as it tries to charge the dead battery. It WILL fry the factory ammeter.

How much current do you believe will open one of these ammeters? If the battery is flat, how do you get it started?

 

[72RoadrunnerGTX]

The Powermaster alternator is a shunt system with a (recommended) fusible link.

It bypasses the factory charging system altogether, however, it does not eliminate the factory fusible link on the starter relay from where the power to the inside of the vehicle is derived so the factory protection is still there.

THIS is why Powermaster says that there's nothing wrong with a "shunt" wire. Theirs is a shunt system, therefore, there's no problem with a shunt. That's NOT the case in any situations except with their one-wire alternator systems.

This is also NOT the case with a ChryCo charging system, however UNLESS you make the a fore-mentioned modifications to the ammeter but it's only a patch to help maintain proper voltage levels at the battery.

If you try and bypass a factory MoPar alternator in the same fashion, the same original fusible link on the starter relay will protect the body harness but the alternator output will NOT be protected unless you add an additional fusible link in your shunt wire but that's still not going to cure your problem.

The reference voltage for your voltage regulator comes off the ignition circuit and if you have faulty bulkhead connections, that reference voltage will be incorrect and your charging system will STILL be screwed up.

The fix, as has been mentioned before, is to repair/replace the bulkhead connections, not a kludge shunt bypass, and THAT will solve your problems, .

Let me get this straight, you are talking about an added parallel wire run (shunt wire) from the alternator output stud to the battery(or the battery terminal on the starter relay), with or without its own circuit protection(optional apparently), overlaying (shunting) the original intact (or somewhat intact) charge path wiring and components, you say this will not alter the stock circuit protection for all the unfused stock wiring in any way? If so, I would refer you back to post #32 of this thread for further info on that. This shunt wire bypass will indeed negatively alter the stock circuit protection to the point being useless in the event of a short, Kirchhoff's current divider rule, no way around it. May have to break out the fixture once more for another video and demonstrate to total failure, stay tuned.

 

[Crackedback]

AC car, running headlights and blower motor on high = never a balanced system at idle on a muscle era mopar.
Same ol stuff with a boatload of qualifiers. The system itself, in a factory car, has never caused a problem, so some say, and that is just NOT TRUE. Jump starting a dead car and having the bulkhead go hot, lovely. Off to ignore, had enough of that.

The stock system is a dumpster fire with the packards which aren't even rated to carry the base alternator 37ish max load... that is a POORLY designed system from the GO. A well designed system should be able to carry the max load limits without failure creeping into the environment. Mopar missed the mark BADLY here. Put a SS hemi in front of a 3 clutch pack 904 and when it fails, don't be surprised. Same here, engineering or bean counters screwed the pooch.

Denial just isn't a river in Africa.

The Shunt wire with a fusible link will provide protection but it raises the failure point very high. The stock fusible link has allowed MANY cars to roast the instrument cluster/dash harnesses in these cars... they aren't the panacea of protection either.

 

[Should be playing golf]

Per Powermaster: Bypass your ammeter; repair/replace old packard connectors; install a voltmeter; run 8 or 6 ga. shunt wire directly to + battery from alt. output; can even install a 120-125 amp Mega fuse or breaker (depending on what alt. output is) in the shunt line to protect everything should the alt freak out. Give them a call if you are confused.