Is it my alternator?

RSchanz

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My neighborhood mechanic told me today that if the battery light on the dash doesn't turn on when I turn the key on it won't charge. He said he's seen people replace the batteries, regulator and alternator and it was just a 50cent bulb. Apparently it needs this in order to excite the regulator. He said, check this first and if it doesn't light up take the dash off and put a new bulb in. Any thoughts? I dont think there is even a battery light on the dash for this model.
 
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Nero

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Maybe on some cars, but not the 1G alternator.
 

RSchanz

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I removed F and used a test wire going straight to positive and got nothing then went to ground and still got nothing. Pretty certain it's the alternator at this point then, right? In the case that I don't have someone rebuild it are there any good aftermarket alternator recommendations?
 

typ4

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Sounds like alt, bat to f is the test. I would do a 3g conversion, Or quick and easy get a reman from auto parts,
 

RSchanz

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Sounds like alt, bat to f is the test. I would do a 3g conversion, Or quick and easy get a reman from auto parts,
Was just re-reading and re-watching swap videos. Seems very easy, only downside is that I'm just going to buy one on amazon or something and not go pick around a junk yard.
 

typ4

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Wire is not missing, it would be a white stator wire and isnt needed if you have an "amp" gauge,


But first,,, make sure your green w red stripe has voltage from ign circuit. and that there is batt voltage at the bat term of alt. Fuse link could be bad.
 

Cubey

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I know on the gasser there is a wire from the alternator to the electric choke, I don't remember which terminal on the alternator though. It could be the one everyone thinks is missing.

James

Nah it's supposed to have another wire. Both IDIs I've had with 1g had 2 wires.

and based on the diagram I posted just above, vans got the same wire colors.

My current 89 that someone switched to 3g. The now unused orange and white-black stripe wires are taped off.

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typ4

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They dont all have the stator wire. 99% do.
 

RSchanz

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Wire is not missing, it would be a white stator wire and isnt needed if you have an "amp" gauge,


But first,,, make sure your green w red stripe has voltage from ign circuit. and that there is batt voltage at the bat term of alt. Fuse link could be bad.
Wouldnt this not matter since I already jumped "F" (green/red) straight to battery positive and ground and got no charge? Guess now that I'm thinking about it I didn't accelerate the truck while touching the test wire but it should the volts should still jump up either way once the alternator fires up right?

Tested with voltmeter red on bat term on the alternator and black on ground. It works but the volts were low like 8 something and jumping around not a great connection. If I recall correctly I can turn the ignition to "ON" and put a test light in "F" (green/red) and it should light up, right?

EDIT: I turned the ignition on and grounded the test light and put it into the "F" wire in the connector on the alternator and it lit up so it's confirmed that this wire is getting power. I think this is probably redundant since I jumped this with the test wire and the alternator still didn't do anything.
 
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RSchanz

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I just want to drop this here too because I was having electrical issues almost a year ago related to the regulator and alternator and @Nero you and I went back a forth a little about this isolator that someone installed. I'm pretty sure this is not a normal thing right? I want to do the 3G swap but I'm concerned that this will complicate things and also I don't know why I even have it...
 

typ4

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Wouldnt this not matter since I already jumped "F" (green/red) straight to battery positive and ground and got no charge? Guess now that I'm thinking about it I didn't accelerate the truck while touching the test wire but it should the volts should still jump up either way once the alternator fires up right?

Tested with voltmeter red on bat term on the alternator and black on ground. It works but the volts were low like 8 something and jumping around not a great connection. If I recall correctly I can turn the ignition to "ON" and put a test light in "F" (green/red) and it should light up, right?

EDIT: I turned the ignition on and grounded the test light and put it into the "F" wire in the connector on the alternator and it lit up so it's confirmed that this wire is getting power. I think this is probably redundant since I jumped this with the test wire and the alternator still didn't do anything.
Regard less of the way you go the green red needs to have voltage on it to make the alt charge . the 3G will not complicate anything.
 

Nero

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The isolator is used for charging batteries on a camper or trailer.

The 3g alternator conversion is really simple to do.
 

RSchanz

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The alternator is off the truck. It was so rusty on the inside and when I took it apart this metal holding these springs in was broken also. Maybe that was part of the problem.

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Just going to swap for 3G following this video:
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MtnHaul

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3G is pretty easy as I recall. Well worth it to simplify the wiring and increase capacity. I think I used 2 gauge for the charging wires and a MegaFuse & holder with rubber cap. Zero problems and seems to put out enough voltage to keep my AGM batteries happy 4+ years now.
 

RSchanz

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I watched this guys video above a couple times and read some things here and there and I'm sort of confused about what happens to the other wires running from the voltage regulator particularly the wire that runs to the tach sensor. Will it still work if I just cap this wire off? What am I supposed to do with that?
 
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