Can someone help? I need to drive my dart tomorrow

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I appreciate that but I will actually not be at work tomorrow. Taking the day to watch the kids and work on the car

pishta said:
bypass it and dont look back.

Catalog

Shaun, do you want me to drop off a squareback dual field alternator and electronic voltage regulator at your work tomorrow morning? between 7:30 and 8 AM.
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The part stores have a yellow butt connector that will shrink and seal with heat ( Bic lighter ). You could snip out all the burned and connect those 2 wires away from that gauge. Then add a volt gauge somewhere.
 
Ok guys a little information here. First thing i did today was check my battery voltage. 13.2 volts with the key off. 12.6 with the key on. Starting, it dropped to about 12 then right back up to 13.5 to 14 at idle. If I rev it it will get up to 17 volts. Sustaining a higher rpm it will keep the voltage over 15 volts. I believe on the highway yesterday I was probably around 17 volts


I took off all connections to alternator and regulator and battery. I cleaned everything and re attached. Same problem. Still over charging.

I removed both wires from the alternator. Did a continuity test on each post, the top post closest to the good did not make a noise when touching a ground point. The bottom connection for the green wire did show continuity however. I’m not sure what this means if anything

At this point I’m wondering if the voltage regulator should have been swapped once the car got electronic ignition? This is something that I read about

What are your thoughts at this point? I always tried another battery and the results were the same. When I remove just the green wire from the ALT, the battery does not charge anymore
 
Shaun65dart said:
Ok guys a little information here. First thing i did today was check my battery voltage. 13.2 volts with the key off. 12.6 with the key on. Starting, it dropped to about 12 then right back up to 13.5 to 14 at idle. If I rev it it will get up to 17 volts. Sustaining a higher rpm it will keep the voltage over 15 volts. I believe on the highway yesterday I was probably around 17 volts
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Relative to the battery's 13.2 or even 14, 17 Volts is high. Power is flowing from the 17 volts down to the 13.2 or 13.5-14 at the battery. Its related to the voltage regulator. All you have to do is determine if its the regulator's internals, or the voltage it's reading. My guess is internal, but this is easy to check.

The easy check is to clip the positive lead of your voltmeter to the the regulator connection, and negative lead to ground. It should be the same voltage as the battery positive and the alternator output. If it is, then the problem is in the regulator. If its lower, then the problem is in the wiring.

Regulator. If its points style, take the cover off and see if the points are stuck. If so, clean with some fine emery and that may be it. If its solid state, toss it in the trash and buy a new one. With solid state, I've had better than average luck with the Standard VR128 regulator. Original application is for Studebakers, so it looks and connects a little different. Its also what Mopar Performance used - except Standard's is better quality. For a solid state regulator that looks more original, do a search here; Slantsixdan seems to keep on top of which regulators have better odds of being a quality product. (I keep a spare VR in stock at all times.)

At this point I’m wondering if the voltage regulator should have been swapped once the car got electronic ignition? This is something that I read about
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That's something you need to find out from Pertronix. Mopar Performance wanted the electronic (solid state) regulator for their ECUs but that's a different animal. I think its a matter of how well they can ignore switching noise from the points.

When I remove just the green wire from the ALT, the battery does not charge anymore
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That's the field wire. Go to the bottom drawing on my Charging page. The bottom drawing is a more complete diagram that includes the regulator. Even though its for a '67 Barracuda, the circuitry is about the same as yours.

So here's how it works. Inside the alternator is an electo-magnet. It gets power from the regulator. The more power it gets, the stronger the magnetic field. Hence - the field wire. When this electromagnet spins, it induces potential current in the windings that surround it. That's the source of the power at the alternator's output terminal.

So you removed the field wire, and the electromagnetic wasn't very magnetic.
 
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Just connected positive lead to top terminal with black wire on alternator at idle. 16 volts

Bottom connection on alternator with green wire, 6.5 volts

Then checked both connections on voltage regulator, 6.5 volts

Voltage at battery is 14.8

All of these measurements are at idle
 
Therefore the voltage is dropping before it gets to the regulator. Start tracing back.

(Heavy post terminal is output, often marked 'BAT', but it feeds everything from the main splice)
 
Show where your Pertronix draws power and we can sketch up what you have.
 
Shaun65dart said:
So the voltage drop before it gets to the regulator is causing the over charging?
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Mattax said:
Another reason for a regulator to full field when it shouldn't is poor connections in its circuit - usually a bad terminal crimp or oxidation at the bulkhead. If the regulator see less the 14.5 ish Volts, its going to let more current through to the alternator's field. The regulator here is just doing its job. If its getting under 14.x volts, it thinks the alternator isn't putting out enough power.
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Mattax said:
The easy check is to clip the positive lead of your voltmeter to the the regulator connection, and negative lead to ground. It should be the same voltage as the battery positive and the alternator output. If it is, then the problem is in the regulator. If its lower, then the problem is in the wiring.

.
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I know what you are trying to say but this does not explain things well

If you check this RUNNING and the problem is a VR that is "full fielding" the alternator, this test is meaningless. This is PARTLY why I always tell guys to check this way:

Leave engine OFF turn key to RUN

Hook one voltmeter lead to the VR IGN terminal, the other to battery POS post. You are hoping for a very low voltage zero would be perfect. Any voltage at this point will be ADDED to a properly working VR, AKA let's say you measure 1.8V in this test, and IF the VR is working OK, this means the charging voltage is gonna be about 14 + 1.8 or 15.8V

The kind of voltage the OP is seeing is likely NOT a VR problem "except."

I would look for............

Badly grounded VR

Wiring problem at the alternator field connections, IE the VR green wire grounded as in say, broken missing insulators in the brush holders

Maybe a completely failed VR.....with engine running, unplug VR and see if it quits charging.

DO NOT DRIVE the car with this situation. You will ruin or explode the battery, and burn up other parts like lights and electronics
 
Sorry to ask this type of question but how should I check to see if the VR is grounded?
 
Shaun65dart said:
Sorry to ask this type of question but how should I check to see if the VR is grounded?
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With an ohmmeter, batt Neg. post to the regulator base, should be .5 or less. The problem You're having has burned many nice Mopars to the ground. Do what Pish said,
bypass that whole set-up, right now all of the cars current draw is going through that gauge. The jumping around could be an internal short/open, and the terminal is
getting hot for that reason, causing it to degrade as You see it. Don't F*#K around with this, it can & has burned up many cars, even pristine examples.....................
 
67Dart273,
I appreciate that your method of checking for voltage drop is safer and more direct. However, Shawn has alread tested with the engine running. We know the VR IGN is not seeing Alternator output voltage, or Battery Voltage. See post 31,
He now needs to find out where the resistance is.
(also, please see post 29, Alternator output voltage is following RPM - the field is getting power all the time)

Killer6,
Yes it is worth checking for ground. However there is voltage drop between the Alternator's output and the Voltage Regulator's Input (aka Ign). See post 31
The ammeter has nothing to do with that. Furthermore, Shawn presumable has bypassed the ammeter either by joining the ring terminals or by doing as Redfish posted.

Shaun,
You've got to tells us where the pertronix ecu is pulling power. Without that, we don't have a full understanding of the power distribution with the key on.

edit: corrected spelling :)
 
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Mattax said:
67Dart273,
I appreciate that your method of checking for voltage drop is safer and more direct. However, Shawn has alread tested with the engine running. We know the VR IGN is not seeing Alternator output voltage, or Battery Voltage. See post 31,
.
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What I'm saying here is, resistance in that circuit is VERY UNLIKELY to cause such severe over charging. A 3? volt drop or more in the ignition feed to the VR would likely never start the engine. Therefore there must be something else wrong as I "guessed" above.

To put it still another way, he may have at least TWO problems........harness voltage drop AND something causing severe over voltage. 17V sounds more like something causing "full field" situation.

Checking with the engine OFF as I detailed will show that this is a harness problem, and if he "let's say" only shows 1 or 2 volts drop with that test, then that will NOT cause the 17V situation

OP: The VR should be normally NOMINAL 14V. So whatever drop you show with the engine off test will be added to that 14V. If you only show .5V drop, then the battery will charge at 14.5. If you show 2V drop, then the battery would charge at 16. But with 2 or more V drop, you are getting to the point where "when cranking" it is unlikely the engine will fire, as you'll only have ?? 7V or so to the ignition to start.
 
Excess resistance between the alternator and the VR would have no effect on starting. Slow down and review from the begining. You're missing a lot that has already been dealt with.
 
The red wire for the Petronix is spliced into a blue wire that goes to what looks like some sort of distribution block on the firewall
 
One lead to positive battery post and one lead to voltage regulator with ignition in run position give me a fluctuating number of about 6 volts
 
Checking to see if VR is grounded. I believe this number would mean that it is?

8CD5F8D5-3632-45A6-B896-5C74950D0394.jpeg
 
With key in run position, the battery says 12.4

The top post with black wire on alternator says 11.1

The green wire on alternator says 5.7

The red wire for petronix says 6.1

Voltage regulator says 5.7

Positive side of coil has 10.5

I do have a brown wire that runs along the valve cover that is not hooked up to anything. That has 6.1 volts
 
Bottom terminal getting 6, top terminal getting 10.5. Bottom terminal goes to the voltage regulator I believe and also an aftermarket tachometer

71760470-2882-4F01-8128-026B45DD8445.jpeg
 
Tested with engine running

Without regulator hooked up the engine stayed running. Numbers as follows with regulator unhooked

Battery 13.1

Regulator wire 12.1

Alternator black wire top post 12.2

Green wire bottom post 0.0
 
Here's what I would do:

- Take off voltage regulator from the firewall and sand away any paint around the boltholes to bare metal. Clean up the back of the screws too. This insures a good ground for the VR and might fix the fluctuating charge-voltage.

- With the ballast resistor, temporary take off the connectors and lightly sand off any of the 'black' of the resistor's male-connectors down to brass color again. Try to clean up the female connectors as well.

- Permanently remove the thick wires off from the ALT-gauge. Clean/sand the wire O-rings to bare metal and bolt them together tightly with a small bolt and nut. Then tape it off real good with no metal protruding, to prevent contacting any other metal parts nearby. Maybe even tie it away from anything else.
 
Shaun,
Just got in and have to run out again but I'll be back in little bit.
Shaun65dart said:
The red wire for the Petronix is spliced into a blue wire that goes to what looks like some sort of distribution block on the firewall
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Does the blue wire go to the ballast resistor? If so, its the "run" wire from the ignition switch.
Is this "distribution block" the one in the photograph earlier in this thread? If so, its the bulkhead connectors.

Shaun65dart said:
Checking to see if VR is grounded. I believe this number would mean that it is?
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Yes. If no ground it would show infinate resistance. You have it on the 200 kOhm scale, and from the LCD so I take it as 0.2 kOhms, if so, that 200 Ohms. Put it on the 200 Ohm scale and see what it shows.

Shaun65dart said:
Bottom terminal getting 6, top terminal getting 10.5. Bottom terminal goes to the voltage regulator I believe and also an aftermarket tachometer
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10.5 is low relative to your supply - This top connection ought to be the RUN and be joined with the wire to the voltage regulator. The 6 volts on the other side of the resistor ought to be the power to the coil positive.
 
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