Charging troubles: Ammeter bad? 1964 Chrysler

[Padre4art]

Good day gents (ladies too!)

I am experiencing charging troubles on my low miles 1964 Chrysler Newport.

It's max rate of charge, per the ammeter, reads just above the center (neutral) line.

If I turn on the blinkers, push on the brakes, or turn on the headlights, the ammeter plummets well below the centerline.

I have heard that ammeters on these models can fail. I don't know if that affects charging.

I am afraid to drive it any distance for fear that the battery will go dead.

I have replaced both the alternator with one professionally rebuilt by one of our trusted members, and also have installed an NOS regulator. No difference whatsoever in how the ammeter shows charging.

Car has been well stored, is not rusty, wires are in good shape.

Thanks

Art

 

[413]

Does it stay low if you raise the engine RPM. Alternator test should not be done at idle. Need to raise RPM to 1200 for testing.

Here is a test. Disconnect green field wire from regulator. With car running at 1200 RPM and a volt meter across the battery you can read, or a helper inside to read the amp meter. Put 12 volts to that green field white at the regulator. Only do this for a few seconds, do not leave it this way it can damage alternator or wiring. It should show the volts around 16 and the amp meter should for to full charge. If it does this the alternator, amp gauge and wiring are good.

 

[Mopars & Missiles]

It's not your ammeter, you stated a slight charge and a substantial discharge in your first post. That shows that the ammeter is working. Too many are scared shitless of an ammeter, mostly because they don't know how electrons work or how an ammeter works. Overall, the Chrysler ammeter is quite reliable.

 

[Gerald Morris]

Good day gents (ladies too!)

I am experiencing charging troubles on my low miles 1964 Chrysler Newport.

It's max rate of charge, per the ammeter, reads just above the center (neutral) line.

If I turn on the blinkers, push on the brakes, or turn on the headlights, the ammeter plummets well below the centerline.

I have heard that ammeters on these models can fail. I don't know if that affects charging.

I am afraid to drive it any distance for fear that the battery will go dead.

I have replaced both the alternator with one professionally rebuilt by one of our trusted members, and also have installed an NOS regulator. No difference whatsoever in how the ammeter shows charging.

Car has been well stored, is not rusty, wires are in good shape.

Thanks

Art

I suspect either a short circuit in your lighting circuits or the headlight switch itself. You mention seeing a significant current draw when you use these lights.

For a 1964 car, you probably should have a fairly low ampacity alternator and charging circuit, given that high current alternators were not common then. The fact that your ammeter shows the draw indicates IT works. If you like, check the wires going into it. 1 comes straight from the alternator, the other from the starter relay.

Try this; disconnect the alternator charging lead altogether, AT the charge stud of the alternator. Then start you engine, let it idle, and try the sundry lights aforementioned. See if the ammeter does anything. Without anything coming in from the alternator, it shouldn't. That's your sanity check.

Now, attach a VOLT meter to your + battery terminal, idle the engine, turn on a suspect light, note the VOLTAGE drop. Is it reasonable? Headlights will draw enough current to drop system voltage a good volt or so, at idle. Then, run your idle up to 1200 rpm, the engine angular velocity at which Mopar alternators should ALL be in FULL charge mode. Note the initial charging voltage, then, turn on your headlights again. Note that voltage.

Now, did system voltage drop the SAME when charging as when not? It should. If not, then something is amiss in your charging loop.

Note the voltage drops for each of the suspect light circuits, comparing them to system voltage at idle, then, at high, charging idle. If the brake lights drop your voltage as much, or more than the headlamps, then go short hunting!

BTW, that's a LOVELY engine compartment! Enviably SIMPLE and CLEAN. New paint looks nice also.

Make a spreadsheet table of your voltages. You can even estimate your current draw, and table that also.

You may have nothing more than a small alternator, say, 27 or 35 amperes. Still, I suspect the headlight switch first, then the brake light conductor, usually pink, and possibly the turn signal leads going through the bulkhead connector as all likely places for poor contacts, short circuits and such.

Yes, you have electrical bugs.

 

[John Reddie]

Just a thought here. How old is the battery. I ask because I had a problem with my "67 Fury once where the ammeter would show just a whisker on the discharge side at night with the heater and headlights on. With all the accessories turned off and the engine sped up, the ammeter would peg as high as it would go indicating that the charging system was trying to put electricity back into the battery. I replaced the alternator, regulator, and checked out all the connections with no improvement.
The battery was an Interstate and 11 months old then. It had caps on the top and when I checked it with a hydrometer, the cells read normal. After experiencing a no start episode, I borrowed another battery and the problem was solved. At 15 MPH and accessories on, it was charging perfectly. I bought a Diehard battery from Sears and things were back to normal.
Good luck to you.
John

 

[Torky]

Good day gents (ladies too!)

I am experiencing charging troubles on my low miles 1964 Chrysler Newport.

It's max rate of charge, per the ammeter, reads just above the center (neutral) line.

If I turn on the blinkers, push on the brakes, or turn on the headlights, the ammeter plummets well below the centerline.

I have heard that ammeters on these models can fail. I don't know if that affects charging.

I am afraid to drive it any distance for fear that the battery will go dead.

I have replaced both the alternator with one professionally rebuilt by one of our trusted members, and also have installed an NOS regulator. No difference whatsoever in how the ammeter shows charging.

Car has been well stored, is not rusty, wires are in good shape. View attachment 745954

Thanks

Art

Nice sanitary view under the hood. The Ammeter in this car is calibrated to read only the current flow in to the battery (charging) or the amount flowing from the battery (alternator not operating or not operating properly). Most auto supply stores will give your system a quick check. You can use an analog (not a digital) to check Voltage at the battery when the engine is running. With everything operating properly, the Voltage at the battery should be 14 Volts +/- 0.5 V. Could be a weak battery or a malfunctioning Voltage regulator. I see a lot of other comments. Probably not the Ammeter. It's just trying to tell you of some other problem or problems. Best wishes. Let us know what you find.