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Old Aug 22, 2023 | 11:09 PM
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Battery draining

Guy's,

The battery in my '41 ton and a half with the V8 keeps completely draining. I've never had a charging problem with this truck, until now. Pretty disappointing since this truck has been extremely reliable. Even in the cold! I could start this thing any day of the year without issue.

So, I have some questions. First, how many volts should the 6V generator be putting out? A little more than 6, correct? Similar to the 13+ volts of a 12v system? I'm pretty sure it's charging okay but I will check again.

If I do have a drain somewhere, is there a place, or device, that I should look at first because its prone to trouble? What has your experience been with any drains you found? How did you find it? Just trying to come up with a plan of attack here. Not sure where to start after the generator.

Thanks in advance for any advice on this!

Steve
 
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Old Aug 23, 2023 | 09:20 AM
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I would start by looking at the voltage regulator. It may be there is a stuck or corroded set of contacts that is causing the issue. Good luck!
 
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Old Aug 24, 2023 | 01:23 PM
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I will look at that. I hope it's something simple! Thanks.

Steve
 
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Old Aug 24, 2023 | 08:13 PM
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How many contacts does a regulator have? I ask because my truck has a retro-fitted generator on it with a Delco-Remy regulator on top of it. (This truck is a former fire truck, it had a non-original style generator on it to start with and the previous owner installed the current one.)

I see one contactor, at the top of a small coil, and it is going up and down, not making contact until the rpm's come up and then releasing at idle. The meter indicates a charge when the rpm's are increased. So, it appears to be charging correctly. Is there another contactor I missed on this regulator that could be my problem?

Assuming the regulator is not the cause of the drain, what should I check next?

Steve
 
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Old Aug 26, 2023 | 05:49 AM
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maybe your ignition switch stays on , remove battery post and touch it lightly to battery check for a spark . if theres a spark theres a electrical draw ,its better to be in a shaded area. you can test by removing or unpluging stuff ( generator radio light heater coil etc ) one at a time until spark is gone . then you know which circuit is doing your problem. you can install a master switch too .
 
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Old Aug 31, 2023 | 02:24 PM
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Originally Posted by bernette
maybe your ignition switch stays on , remove battery post and touch it lightly to battery check for a spark . if theres a spark theres a electrical draw ,its better to be in a shaded area. you can test by removing or unpluging stuff ( generator radio light heater coil etc ) one at a time until spark is gone . then you know which circuit is doing your problem. you can install a master switch too .
A better way to check for a battery drain is start with a fully charged battery, THAT IS A MUST!

Battery disconnected and a test light, in your case a 6 volt light would be better than a 12 volt as a 12 volt might be too dim to see.
Hook up the test light between battery post and the cable.
With everything turned off the test light should be off. Dose the truck have lights inside that come on with doors open?
This dome light on with door open will light up the test light. The brighter the test light the larger the drain.

As said start disconnecting / unplugging stuff.
On newer stuff I would start on removing 1 fuse at a time, leave them out, till the test light goes out.
What that fuse supplies is the area you need to look for the drain.

Now if all the fuses are out and still have a drain remove the wires from the ALT GEN and see if it goes out.
Test light still on tape up the wires and remove the wires on the regulator and check light.
You have to get to a point that all loads and no longer on the battery and the light is off.

BTW have you tried charging the battery and letting it sit a day and see if it holds a charge?
Battery could be bad and you would be going after your tail LOL
Dave ----
 
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