Battery becoming very hot

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Eddie348

Eddie348

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Turned the Dart on today and after warm up Battery was very hot. exchanged the battery and the new battery also became hot. Changed the VR as well and still same issue. Any Advice what to try next? Thank you
 
You need to measure the charging voltage. Make sure connections are tight especially the grounds.
 
Thank you Mike. I have and also the Ammeter is jumping and the needle is buried to the C side at times.
 
sounds like an intermittent short to ground. When my Ram charger buried the Ammeter needle to 'C' , it was because the field wire melted where it goes over the heat riser crossover on the right side of the intake manifold. But if that is your case, it could be somewhere else.
 
Thank you Rusty. All wires were checked and I think Wire at the Bulkhead was loose. Going for a ride tomorrow will see what happens
 
A loose wire at the bulkhead can melt the bulkhead. Common problems. Search "MAD Bypass" for many, many posts.
 
Bill good evening. Will be working on it tomorrow. Thank you
 
Have you changed a regulator lately? Or painted the firewall?
 
Good evening. Changed the VR after the issue of the battery.
 
Eddie348 said:
Good evening. Changed the VR after the issue of the battery.
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I ask because the electronic regulators control the output through the case ground to the firewall. I replaced the old point type regulator with a new electronic one that was poorly grounded. I boiled the battery and blew out some bulbs. It could have been worse.
 
Mike thanks for the heads up I will check that the VR is grounded. Thanks for the heads up
 
Pull the VR connector off and see if it keeps on charging. The green wire brush may be grounded in the alternator. Neither brush with field wires disconnected should show continuity to ground.

THE VR MUST BE GROUNDED. Do not drive it this way.

TIME TO make some voltage checks We can step you through some of this.
 
Eddie348 said:
Thank you Mike. I have and also the Ammeter is jumping and the needle is buried to the C side at times.
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These are big clues!
The needle all the way over means over 30 or 40 amps is going to the battery. A battery only draws that type of current if it is drained or the system voltage (generated by the alternator) is well above 14.2 V, more like something over 15 V.

Jumping needle could mean several things. If it was moving up and down with engine rpm, then the voltage regulation is probably on full field, full time.
If it seems random; its almost certainly a loose connection that is making the voltage in the blue feed wire see low voltage or a ground short...

67Dart273 said:
Pull the VR connector off and see if it keeps on charging. The green wire brush may be grounded in the alternator. Neither brush with field wires disconnected should show continuity to ground.
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^^This is a great test^^ that can be done without a multimeter.

Note: Both the older style positive regulator and the newer style grounding regulator need good grounds!
 
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Reading Your Ammeter
The ammeter shows current to or from the battery, not including power to the starter.
  • It should show small steady discharge when starting.
  • It should show 15-20 amps charging at most after starting, quickly dropping to 5 amps or less.
  • After a few minutes of driving, the ammeter should show zero current.
If it ever pegs discharge, there is a dangerous short. Do not drive. Shut off all switched power. If the short is on an 'always hot' circuit, the fusible link will melt.

If it charges high due to discharged battery, try low rpms to reduce alternator power, turning on headlight and fan to divert some of the current from over charging the battery. Stop and allow battery (and wires) to cool off if charging rate does not come down. Use a slow charger if possible.

Understanding Charging Systems with Ammeter:
 
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Good afternoon. Update- all wires checked, grounded and needle is now between the middle and C. Put on the brakes, turn signals, headlights and needle starts bouncing. Any ideas? Thank you all for the great advise and direction. Next check voltage.
 
Amp gauge needles will move with the slightest current draw. You can watch the turn signals light with the needle. I wouldn't call it bouncing though. If it bounces to the stop on the charge side you have issues. A voltage check should be your first plan of attack followed by a complete battery load and hydrometer test.
 
The turn signals and hazzards will cause fluctuationin. See if it goes away with those off.
Yes go ahead with checking sytem voltage at idle. The battery stud , tbe alternator stud, field hot (blue) should all read the same,)
Increase rpm, and if voltage increases much above 14.8, problem its related to regulation or lack of it.
 
I bought a few of these for my old cars. I haven''t got them yet but volts/amps and 2 usb ports.
Capture.JPG
 
Check all the running insert-and-twist bulbs to make sure they are the correct bulbs in the correct sockets, and correctly installed. If you don't find an issue there, check the side markers. 194 type bulbs have been known to short if not carefully installed.
On bulbs with two filaments, check that they both light independently, at proper intensity; I have seen those shorted inside the envelope, one to the other, or a pool of melted metal in the bottom.
If the needle bounces around with the brake lights lit, check those first.
If everything turns out hunky-dory, start pulling fuses, the problem might be in the signal switch itself, which is a type of signal router. The cheap aftermarket ones are known to melt, and anything could happen.
 
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Good evening. Checking the lights now. Also can a loose alternator belt cause the issue? Thank you

Any steps on the volt checks?
 
Eddie348 said:
Good evening. Checking the lights now. Also can a loose alternator belt cause the issue? Thank you

Any steps on the volt checks?
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Gosh yes.
Very first thing.
Turn the lights on for 15 seconds or so if its just been running or on a charger.
^ This removes any surface charge which would show on a voltmeter but does not have power.
Measure the battery voltage with everything off. (The ammeter should be at zero)
If its 12.5 to 12.8 Volts, turn on the headlights and see what it drops to. It should still stay above 12 Volts.
^This is a very crude way to check battery condition, but it will show general battery condition.
If its less than 12.5 Volts with everything off, then one reason the ammeter is showing high charge is because the battery is discharged.

Next, Start the engine.
Measure the voltage from battery neg to battery positive.
Note the ammeter reading, and whether the engine is on slow idle or fast idle.
If its over 14.8 Volts or so, the regulator is probably reading low because there is resistance in the connections or wires.

If its on normal idle (650 rpm or so), use your hand to work the throttle lever at the carb to increase rpm. If the voltage increases with rpm, don't let it go over 15 Volts. Let it go back to idle. There's a problem with regulation, there is none.

That's enough for initial diagnose.

If voltage is following the rpms, you can do the test 67Dart273 suggested: Pull the connector off the voltage regulator. Ammeter should swing to discharge (because the ignition is running on battery, and voltage should drop to battery voltage, 12 something.)
 
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Overcharging is the real issue at hand. Loose alternator belt or lamps are not going to be causing that.
Overcharging is caused by the regulation not working or getting wrong information. There is a small possibility the battery is just drained and needs a slow charge.
 
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