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Got a hot alternator like really hot, smelled it cooking. Looked at a few topic on here, started tracing wires. I previously rebuilt the whole harness-check all wires and re sheathed, tape, etc. My dumb a$$ forgot one wire the ground on the fuse box. Attached pic is what I missed. Is this wire straight to ground/frame? If it is I know which wire I need to use...

Additionally could this mistake cause the hot alternator? Both alternator and batteries are old... alternator I assume to be original, batteries around 5-6 years. Batteries took trickle charge and started truck up fine. 

Thank you. 

20200715_113125.jpg

Edited by Stanley
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That is NOT A GROUND terminal! DO NOT ground that it will blow the alternator fuse there. This is the alternator charge stud. No longer used if you did the W-T ground wire mod.

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2 hours ago, Stanley said:

Ok, I knew I had something connected there, can even see where the terminal was. I cant find it?! ?

I didnt do the w-t mod yet. 

Where does the wire from there go? Would that explain the scalding alternator?

 

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If the W-T ground wire mod was done which is typically why there is nothing to hook up. The wire from the back of the alternator goes to the passenger battery. The charge lead is typically removed from the front loom and the re-wired to the passenger side battery. Now the ECM ground and VP44 ground is shortened and hooked to the gear case near the VP44.

 

So even on my truck that stud is now empty. 

 

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I guess I'm confused on what I'm missing at the fuse box. If I can find what I did or didnt hook up to that location I can go from there. After that missing link is found I can then proceed with possibly doing the w-t mod. If that makes sense. Thanks. 

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Make sure neither of your batteries have an internal shorted cell. That is what caused my alternator to get smokin hot. I changed the batteries and the alternator at the same time and all is well. Most of these paralleled two battery systems, the batteries last longer than 5-6 yrs if taken care of and  were never over discharged or never allowed to sit for very long in a discharged state.

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Batteries did sit for awhile, I think batteries and alternator is to blame. I ohm the main cable from alternator over to battery. Should it go to pos. neg. or the missing terminal place. Here is a Video of everything I took real quick. Hope the link works. 

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Posted (edited)
57 minutes ago, Mopar1973Man said:

Should never start a engine with a weak battery or tired batteries this will create massive heat in the batteries and alternator to make up for the loss.

 

I agree, however the batteries were charged on a trickle charger prior to and motor rolled over rather quickly. I dont doubt that the batteries could still be bad though.. 

If you by chance had time to watch that video, that main wire should go where?

 

Is that the one that goes to the fuse box, and you suggested to route it directly to the passenger side pos. battery?

Edited by Stanley
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Posted (edited)

ECM and VP44 grounds go to the gear case next to the VP44. 5 wires Black and Tan...

 

Alternator charge lead goes from the alternator to a 150A circuit breaker or 150 Amp fuse then to the passenger battery POSITIVE.

Edited by Mopar1973Man
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4 hours ago, Stanley said:

I ohm the main cable from alternator over to battery

 

There is little value in using an ohmmeter to check for continuity on high amperage circuits.  Even if only one strand of wire in the circuit makes a connection, the ohmmeter will read zero resistance, indicating the circuit is okay.  The best method for testing high amperage circuits is to perform a voltage drop test on the circuit while the circuit is under a load. 

 

- John

Edited by Tractorman
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1 minute ago, Tractorman said:

 

There is no value in using an ohmmeter to check for continuity on high amperage circuits.  Even if only one strand of wire in the circuit makes a connection, the ohmmeter will read zero resistance, indicating the circuit is okay.  The best method for testing high amperage circuits is to perform a voltage drop test on the circuit while the circuit is under a load. 

 

- John

 

 

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@Tractorman I guess I should have stated checking continuity/ohms lol in that wire just to make sure I had the same wire end to end.

 

Now that I found the end of the alt cable I have forgotten where it goes, hence the video etc. Which kinda explains it all. I can make another one to help clarify if that helps. Where does it go? 

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Posted (edited)
3 hours ago, Stanley said:

@Tractorman I guess I should have stated checking continuity/ohms lol in that wire just to make sure I had the same wire end to end.

 

Now that I found the end of the alt cable I have forgotten where it goes, hence the video etc. Which kinda explains it all. I can make another one to help clarify if that helps. Where does it go? 

The main charge wire off the Alternator gets pulled out of the wire harness going across the front. Gets cut shorter to go the passenger battery positive post. You will need to solder a new ring terminal.

 

Very important to complete all the items to the W-T modifications at the same time.

 

Your truck looks clean, nice :thumbup2:

Edited by JAG1
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If you have not done WT's ground mod, the charge wire would go to the terminal that is missing a wire on the PDC in your 1st picture. That is the factory set up.. That all changes when you do the ground mod. I am assuming you have not done the ground mod by WT as of yet.

 

Where do you have the charge wire landed now?

Edited by dripley
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17 hours ago, Mopar1973Man said:

Should never start a engine with a weak battery or tired batteries this will create massive heat in the batteries and alternator to make up for the loss.

 

I get massive heat from MoparMan when he's trying to make up a loss and don't donate to the site. :lol:

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Thank yall so much, now I'm tracking on what I need to do. Thanks for the kinds words JAG1 just finished alot of work on the entire drive train engine, trans, and t case was completely gutted and redone and rebuilt minus engine internals. Alot of other stuff too. Rocking on 2 years of work to this dang thing. This last little hiccup threw me for a loop. Gonna replace alternator just cause its prolly toast by now? And batteries are pretty old. 

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