Battery not charging

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pnajera01

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So I was having some problems with my truck. It started off as an engine surge went from 0-1000 rpm then shut off. i took the battery in to Oreillys and they said it was bad so i bought a new battery, everything ran great for a few days then the truck just died and wasnt cranking anymore. i took the battery back in and had it charged up then i had them test my alternator they said that was bad too. i bought a new alternator and guess what it happened yet again a couple days later. The batt is only receiving 12.4 volts when on. Could it be the voltage regulator gone bad?
 

crazzywolfie

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it could be a bad voltage regulator. before replacing the battery or alternator i would have checked the voltage regulator. most of the time that is really the issue. it is pretty rare that the alternators on these things ever go bad. could possibly be a bad ground connection to the alternator. i am fighting with that issue on my 81. i am too lazy to take it all apart so i currently got jumper cables grounding the alternator
 
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pnajera01

pnajera01

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I replaced the voltage regulator and the batt is still not charging. I also ran a ground wire straight from the ground post on the alt to the neg batt terminal to see if that was the issue and still no charge to the battery. Dont know what else it could be.
 

crazzywolfie

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have you check to see if there is power being put out at the alternator? does the voltage regulator have a good ground? you may also want to check voltage reading to the voltage regulator and alternator. the 1 wire should be getting 12V
 
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pnajera01

pnajera01

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Finally had some time to do some more digging. I checked the grounds on the v/r and its good. I even went to the extend to ground it to the alternator itself. Ran through all the grounds sanded and cleaned them, they all check good. I turned the truck on and was checking the voltage reading coming out of the alt but before the battery. It said 1.9v. Im not sure if thats what its supposed to be, i assumed it would be 14v since essentially that wire that I was checking is running to the battery.
 

crazzywolfie

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were you checking at on the largest wire at the alternator? if so then yes that should have the same voltage as the battery. you should also see the same battery voltage at one of the smaller wires that hooks to the alternator but you may need to disconnect the wires to see the 12v.
 
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pnajera01

pnajera01

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Yeah it was the largest wire leaving the alt and running to the battery. About halfway on the wire it disconnects and that is where i checked it. Whth the truck on, and the wire disconnected i checked the connecting wire to the alt it was reading 1.9v, but on the end that was connected to the battery it was reading 12v. When the wire is connected and the truck turned off it read 12v all the way to the termial on the alt. No clue what the problem would be.
 

crazzywolfie

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it is possible that you have a bad or broken fusible link. they are on the driver side fender. you could probably get away with running a temporary power wire from the battery to alternator to test to see if that is your issue. if the main power wire is your issue a temporary wire from the alternator output to the battery should have the battery charging.
 
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pnajera01

pnajera01

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Finally had time to figure out the problem! Turns out that along with the alternator going bad, and a bad battery the connector that plugs into the V/r was faulty. When i would put a multimeter to it, it would be getting power but once it was plugged in nothing would happen. So i spliced a plug i had laying around and replaced the v/r yet again, i think oreillys gave me a bad part. So pretty much after damn near replacing the entire charging system it all worked.
 
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