Alternator overcharging

[Apewalski440]

Hi everyone !

Here my specs :
1970 Challenger
Engine is a 73 440.
MSD 6AL
Sniper EFI (1)
Dual Sync distributor.

My alternator is overcharging, it's a Powermaster 7019, when I start the engine the battery go up to 16 at 1200 RPM. I installed a new Mopar Performance voltage regulator, new ballast ignition. Chargewire is 6 gauges for 7 ft. I cleaned the alternator brackets for the ground, cleaned the back of the voltage regulator and the firewall, added a wire from the voltage regulator directly to the engine for a better ground.
The ammerter is not connected to the alternator (read it can cause dammage with a more powerfull alternator), instead there is the chargewire, install directly to battery (next to the Sniper EFI).
Everything look okay, but still overcharging.
I show you picture of my install, maybe you can see if something is wrong.

Thanks a lot.

 

[72RoadRunnerGTX]

First thing would be to verify the regulator has control of the alternator output voltage, disconnect the regulator, see if all charging stops while running. Looks like a full field voltage level. If it stops, next verify there is no voltage drop issue at the regulator ignition 1 wire. Curious where you read about your wiring mods, there are some serious concerns about that direct battery to alternator wire run. Especially without any circuit protection as pictured.

 

[Apewalski440]

Thanks for the video 72RoadRunnerGTX, I will check that.
Before I install the charge wire, the battery didn't charge, it was stuck around 12/12.5.

Here the instructions for the Powermaster alternator and for the charge wire :

 

[pschlosser]

Focus on the voltage regulator, because that's it's job, to regulate the voltage. From the 1970 (for example) FSM

Looking over your images, I don't see anything obviously wrong. I see "wrap around" loom tape on your wiring harnesses. Someone took some time to make everything look neat. But this also means your wiring, and/or how things are connected, could be non-standard and may deviate from the factory wiring arrangement.

Most of us have experience with, and base our comments upon, the presumed wiring of YOUR engine. Can you give us an idea how YOUR system is currently wired? If you're unsure, and you cannot find the problem, I would make it high on my list to confirm how much your wiring adheres or deviates from the factory wiring diagram (found in the FSM)

Generally, the B(attery) output of the alternator (externally regulated by the voltage regulator) runs into the passenger compartment (bulkhead #18) and through the Ammeter gauge and back out to the engine compartment (bulkhead #16) through the fusible link (important !) and on to the battery positive.

It looks like in your case, you bypass the fusible link (not recommended) and ammeter.

 

[72RoadRunnerGTX]

Here the instructions for the Powermaster alternator and for the charge wire :

That’s why I don’t recommend Powermaster, it’s more complicated than that for Chrysler products from this time.

 

[Apewalski440]

Focus on the voltage regulator, because that's it's job, to regulate the voltage. From the 1970 (for example) FSM
View attachment 145315


Looking over your images, I don't see anything obviously wrong. I see "wrap around" loom tape on your wiring harnesses. Someone took some time to make everything look neat. But this also means your wiring, and/or how things are connected, could be non-standard and may deviate from the factory wiring arrangement.

Most of us have experience with, and base our comments upon, the presumed wiring of YOUR engine. Can you give us an idea how YOUR system is currently wired? If you're unsure, and you cannot find the problem, I would make it high on my list to confirm how much your wiring adheres or deviates from the factory wiring diagram (found in the FSM)

Generally, the B(attery) output of the alternator (externally regulated by the voltage regulator) runs into the passenger compartment (bulkhead #18) and through the Ammeter gauge and back out to the engine compartment (bulkhead #16) through the fusible link (important !) and on to the battery positive.

It looks like in your case, you bypass the fusible link (not recommended) and ammeter.

Yes I can tell you how the car is wired, I wired it myself ten years ago, all the harness are from YearOne

(here the engine harness : https://www.yearone.com/Product/Challenger-Cuda/HU107E (1000-10) - 1970-1970)

Yes I bypass the Ammeter, I read more powerfull alternator can burn Ammeter.

I will try to list the differences with the factory wiring :

- The coil is directly wired to the MSD6AL (and the MSD6AL is connected to the factory + of the coil)
- The Sniper EFI control timing, so the distributor is connected directly to the Sniper.

- On the alternator field, like you can see on the picture, I have 2 blue wires on one field, but when I look the wiring diagram, I just see one blue wire, is that normal ?

And an other thing, the Ammeter is wired (before the bypass) in an other way than the wiring diagram : in the wiring diagram, black wire is on the left, red on the right, my Ammeter work with the red on the left (so on the C side of the gauge) and black wire on the right (D side of the gauge). On the back side of the cluster, the is RED write on the left (so C side of the gauge), that's why I thought I was good. It's not a 70' cluster, it's later, the button to reset the miles is on the right size of the speedometer, not in the center.

 

[Apewalski440]

That’s why I don’t recommend Powermaster, it’s more complicated than that for Chrysler products from this time.

Okay, I did not try to connect the Ammeter because it's in the same place as the charge wire, I'm not an electrical expert, so I didn't want to wire together a black and a red (positif) wire on the same place, but do you think I can try ?

Because I see with your video, without the Ammeter connected, I bypass the ignition, and without the ignition ballast the voltage regulator could not work ?

 

[sixpactogo]

I too suspect the regulator. I believe the alternator wants to put out around 17 volts constantly. The battery only want about 14 volts. The regulator's job is to do just that. Regulate. Some are adjustable some are not. If your connections are proper as it seems they are, I would try a different regulator to see if that makes a difference.

 

[Apewalski440]

I too suspect the regulator. I believe the alternator wants to put out around 17 volts constantly. The battery only want about 14 volts. The regulator's job is to do just that. Regulate. Some are adjustable some are not. If your connections are proper as it seems they are, I would try a different regulator to see if that makes a difference.

AI tried with 3 different regulator, with a tuff stuff (7545), with the regulator that was in the car when I bought it, and a Mopar Performance, I think I must have made a mistake with the connection.

 

[pschlosser]

- On the alternator field, like you can see on the picture, I have 2 blue wires on one field, but when I look the wiring diagram, I just see one blue wire, is that normal ?

It is normal, if it feeds power up to the carburetor. The factory 1970 440 HP, for example, had an idle speed solenoid at the carburetor, and a blue wire FROM the alternator feeds power to that when the engine/ignition is in run position.

Since you're using a reproduction of a factory harness, if it's for an engine-year that comes with a solenoid, it is likely that is where the wire is supposed to go. It usually terminates to a bullet connector.

 

[pschlosser]

I think I must have made a mistake with the connection.

If the voltage regulator were regulating, then you would not see 16V at the battery. If you believe one or more of your regulators are in proper working order, it seems the only thing left is a wiring issue.

You may need to go validate how things are currently wired. And if you want to make it easier on us and others to help you, showing the mods to the factory wiring will be VERY helpful. By showing, I mean posting a schematic of how you have things wired. This will minimize the guess-work.

edit: if you wired this up 10 years ago, has it been broken and making 16V all that time? If not, what has changed since the time you felt it worked properly and its present condition?

 

[Chryco Psycho]

Powermaster is not a good brand often they will only last a few hours I would have it tested by a rebuilder locally .

 

[Apewalski440]

If the voltage regulator were regulating, then you would not see 16V at the battery. If you believe one or more of your regulators are in proper working order, it seems the only thing left is a wiring issue.

You may need to go validate how things are currently wired. And if you want to make it easier on us and others to help you, showing the mods to the factory wiring will be VERY helpful. By showing, I mean posting a schematic of how you have things wired. This will minimize the guess-work.

edit: if you wired this up 10 years ago, has it been broken and making 16V all that time? If not, what has changed since the time you felt it worked properly and its present conditio

I think it never worked good, changed the alternator in 2017 (I don't remember why), wired it like the old one. Never have low battery problem. Install the Sniper EFI some years ago, guys on the Holley forum seen my voltage was too low in my datalog, so I changed the voltage regulator (for a Tuff Stuff), started the engine, go up to 13. Don't notice before, but some weeks ago I seen my voltage was still low, had some hard hot starts. I did some resarch and seen the Powermaster needed a charge wire, but with the charge wire it's overcharging.

I will try to put back the Ammeter on the alternator, in the same place as the charge wire, just for see a few seconds.

Powermaster is not a good brand often they will only last a few hours I would have it tested by a rebuilder locally .

and maybe try with the old alternator...

Thanks everyone.

 

[Chryco Psycho]

I installed a brand new Powermaster alt that literally did not last 1 day

 

[pschlosser]

I have hope ( for @Apewalski440 ) that the Powermaster alternator is not the issue, and that he would see overvoltage of even an OEM alternator, were is connected the same way.

But I agree with @Chryco Psycho that the higher power output of the Powermaster forces one to wire it differently, and as such, may confound even the best of us to solve.

Bad Powermaster reputation aside, if going back to an OEM alternator is an option, at least for testing, it seems possible with the OEM alternator, once the problem is found, you may be able to swap the Powermaster back in without issue.

The Powermaster specs (90A+) are pretty nice. But they DO seem overkill, especially in our modern era of LED headlights. On most cases, the 440 came with a 40A alternator. And I've heard and seen many upgrades to (an OEM) 60A in an effort to improve lower RPM output (so the lights dim less at idle and stop lights).

60-amp isn't enough in most cases to cook the factory wiring.

When it comes to Mopars (and most other vehicles) when a mod creates (or seems to create) a problem, I've had the best results putting things back to the factory setup, one step at a time, testing as I go. In nearly every case I can recall, I eventually found the issue.

Once found, one can better decide if they want to go forward with the mod.

 

[Challenger RTA]

Let me put it a different way.
In short.: Disconnect the regulator, see if it stops charging when running.

 

[Challenger RTA]

Mopar charging system

Mopar charging, Voltage regulator. This is for stock Mopar charging system. 1:With the key in the off position. Should have at the alternator output post battery voltage. 2:The field wires should both read zero we should have no voltage. 3: If there is voltage at the field wires with the...

www.forebodiesonly.com

Mopar charging, Voltage regulator.

This is for stock Mopar charging system.

1:With the key in the off position. Should have at the alternator output post battery voltage.

2:The field wires should both read zero, should have no voltage.

3: If there is voltage at the field wires with the key off, there is a wiring problem.

4: If no voltage here at the alternator output with the key off then we likely have either a dead battery or we have a wiring problem or blown fusible link.

5: With the key in the on position. there will be voltage at the alternator output, it's going to be lower than what it was with the key off, because the entire vehicle is energized. The voltage drop is going to be more you can still you can see it go from
12 and a half down to 11.7. Still going to have near battery voltage.

6: What's important. With the key on. The field wires should have voltage. It won't be full battery voltage but it's has power coming to the alternator and it will be a lot less on one side and one side is high. That's the inlet so that's power going into the field windings.
The other one, the one that's low is the output from the field windings.
The output from the field winding is what goes back to the voltage regulator.
The voltage regulator on this is simply a switch ( Remember it needs a good ground to function.) all it's going to do is connect this field terminal here to ground and when it connects it to ground electricity then flows through the field windings energizing it and causing the alternator to charge.

7: Run test: This is for stock Mopar charging system.
Before doing the run test you're going to want to connect directly to the field output terminal on the alternator, with some sort of a jumper wire. You can remove the existing field wire if it helps you to get to it. Use a jumper wire that comes back to the battery and it's not connected to anything right now. Have the voltage meter connected to the battery. Just checking battery voltage 12.3 volts there abouts. By touching the jumper wire to the negative terminal.
Just grounding it you can hear the engine load up because it's pulling a load and the voltage runs up to 14V. That tells you that when the field in the alternator is energized it's charging. The alternator is good. Now you know that it's not an alternator problem at this point. If it's not charging you have a no charge scenario but this passes then you know it's the voltage regulator or some wire up to it. it's most likely the voltage regulator and that's all it takes to diagnose the charging system on one of these.
Here again If the any ground is bad or loose. it won't charge correctly or reliability. They become phantom grounds that just keep haunting you! That being the Voltage regulator ground, chassis ground, engine ground, Bolts, bolt holes, nuts and mounting brackets. 99% of the time there overlooked. The whole car is a ground.
That's all I have to say about that!

 

[72RoadRunnerGTX]

In short.: Disconnect the regulator, see if all charging stops while running.

Second that, but that sounds awfully familiar. Post #2.

 

[Challenger RTA]

Second that, but that sounds awfully familiar. Post #2.

Great minds think alike!

 

[Apewalski440]

Thanks for your help, keep you informed.