Battery becoming very hot

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Eddie348 said:
Thank you. Battery and VR are brand new
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LOL. Hopefully that means they are good. But, your testing will verify they are good; and if so, it will narrow down the reasons why its overcharging.

It's LOL because so much stuff is sold these days that for various reasons is not up to snuff. We've all been burned by new parts that don't work. Its pretty frustrating of course.
 
Good evening. Understood, back to the drawing board tomorrow after work. Will do all the checks and see what transpires. Thank you
 
Good evening all. Finally had some time to perform the voltage tests. Battery off 12v. Turn on car Volts 14.3 at Battery and 14.17 at Alternator. Disconnected VR ammeter went to the center. Checked all the grounds and cable to block ground as well. All paint taken off the firewall as well. Ammeter still half way to the C side. Lights turned on brakes pressed needle goes to the C. Still a mystery but I know soon it will be resolved. Thanks
 
Eddie348 said:
Ammeter still half way to the C side. Lights turned on brakes pressed needle goes to the C.
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Let me be sure I got this right.
Engine Running after start:
Ammeter shows 1/2 way between 0 and C. 14.3 Volts at Alternator and 14.2 at Battery. 0.1 V drop for 20 amps isn't terrible.
Then
Turn on Headlights and apply brakes and the ammeter swings to the C.
Is that right???

Is this is completely stock 1970?
No modifications or additions?

As far as 20 amps charging. That's not surprising if the battery was only 12.0 Volts with everything off.
 
This is correct. 69 340 - small cam, headers, powemaster alternator and a ld 340 with 625 holley. No accessories at all. Checked the pigtail from the VR and it looked in good shape. Thanks
 
Its impossible for the headlights to cause the ammeter to show more charging unless something was modified.
'69 is a little different than '70 that's why I asked.
Post some pictures if you can. Battery and starter relay is where people often wrongly add circuits.

Also, you didn't say what the idle speed was when you checked and whether the voltage changed with rpm.
 
Voltage did not change with RPM.
900 idle speed. Will post photos tomorrow.

I did notice as I was checking all the switches that when I accidentally pressed the wiper switch car wanted to turn off. Like a starter kill. Thanks
 
Eddie348 said:
Voltage did not change with RPM.
900 idle speed. Will post photos tomorrow.

I did notice as I was checking all the switches that when I accidentally pressed the wiper switch car wanted to turn off. Like a starter kill. Thanks
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So far, from what you've posted, the charging is normal for a low battery. I like to see 12.5 to 12.8 V when the engine is off.

A hidden kill switch, eh. Maybe you have some James Bond stuff in there. LOL.
Yea something is up with that
 
Battery is no longer getting hot . Car was on for 1 hour
 
This is the main circuit (supplies power from either the battery or the alternator).
Solid circle or square represents a spliced junction. Open circle or square represents a connector.
Notice where the ammeter is in the line.
Also notice that even with key switch off, all of the lines attached to the battery up to the key switch are still hot. They all will show battery voltage but no current is flowing.

Charging-diagram6x.png
 
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Here is the same circuit with orange arrows representing current flow.
With the engine turning 900 rpm, the alternator was suppling all of the power at 14.3 Volts or so. Therefore,
current flows from the alternator to everything that demands it.
Charging-diagram6x-chargingplus.png

The battery is drawing the most, 20 to 25 amps, because its low.
Points ignition and alternator field, say 4 amps. Notice this flows from the junction up through the key switch.
Lights, about 12 amps. It too flows from the main junction; headlight current goes directly to the headlight switch, there's a circuit breaker inside. Parking and Brake light current goes through the fusebox.

As the battery gets recharged, the current through the ammeter should go to zero.
Hopefully this also makes clear why we were puzzled that lights on would show increased charging.
 
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Good afternoon all. Please see photos of the wiring under the hood.
IMG_20181027_164906.jpg
IMG_20181027_164858.jpg
IMG_20181027_164826.jpg
IMG_20181027_164755.jpg
IMG_20181027_164749.jpg
IMG_20181027_164741.jpg
 
Lights off Idle
IMG_20181027_171948.jpg

Lights on @ idle
IMG_20181027_171943.jpg


Voltage w/ lights on

IMG_20181027_171954.jpg
 
I would have started with a fully charged battery.
Thats why battery was heating up. Was low.

I have seen brand new dud regulators,alternators,starters and batteries.
 
Tooljunkie said:
I would have started with a fully charged battery.
Thats why battery was heating up. Was low.

I have seen brand new dud regulators,alternators,starters and batteries.
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Agree very much!
 
Keep in mind,an alternator is not a battery charger. Its better for a low battery to be trickle charged.
Always better-2 amps for 24 hours.

My seasonal batteries all get a rotating charge- 2 amp automatic charger.
 
Tooljunkie said:
Keep in mind,an alternator is not a battery charger. Its better for a low battery to be trickle charged.
Always better-2 amps for 24 hours.

My seasonal batteries all get a rotating charge- 2 amp automatic charger.
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Agreed!
 
Yes battery was and is fully charged. No longer heating up. Question now why does ammeter not go in center and bounces when breaks are depressed and lights are turned on. Thanks
 
Eddie348 said:
Question now why does ammeter not go in center and bounces when breaks are depressed and lights are turned on. Thanks
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Well, the pictures show the wiring under the hood has been modified. So we need to figure out what modification was done wrong. Don't worry, it shouldn't be that hard. We just need to follow the wires.
Can you follow the diagrams in post 36 & 37?
If so, do you see how the headlights couldn't effect the ammeter in the original layout?

If you have trouble reading or following the diagram, just ask whatever doesn't make sense.
 
Eddie348 said:
Yes battery was and is fully charged. No longer heating up. Question now why does ammeter not go in center and bounces when breaks are depressed and lights are turned on. Thanks
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Agreed that's not right for a healthy system. Good to see the ammeter. Bad connections somewhere. Possibly bulkhead connector but I don't know exactly how and where to test. Hopefully someone will chime in.
 
toolmanmike said:
Agreed that's not right for a healthy system. Good to see the ammeter. Bad connections somewhere. Possibly bulkhead connector but I don't know exactly how and where to test. Hopefully someone will chime in.
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Right here Mike. :) Refresh the page.
Working my way through the photos and waiting for Eddie to check back in.
An 70 up voltage regulator and Mopar performance chrome box were spliced in. Neither of those should cause this. I suspect something else was done at the same time but we'll need to follow the wires...
 
I would consider a 1/2 smoked ammeter above anything else.
 
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