Alternator not charging
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Cross-Country
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Alternator not charging
I’ve got a 1974 F250 with a 390FE and I have a few accessories that require an alternator above 65 Amps so I bought the same type, 1g, 4 wire, 100 amp. The first time I put it in it didn’t charge my battery which was odd, so I put the old 65 amp back in and that wouldn’t charge my battery either after it literally just did an hour before. It ended up being a bad voltage regulator so I replaced that with a 12v one from oreilys. Well I took the new 100 amp alternator to oreilys to get tested because I’ve put it in about 5 times and it still doesn’t charge, and it tested good, so I went home and put it back in today and reclocked the alternator to see if that would change anything and it didn’t.
Im so lost because my 65 amp alt charges it’s just not big enough so I need to get this 100 amp to work. No fusible links are blown, I actually converted them to regular fuses. Im just so lost I have no idea what to do. The ground wire is new and runs straight to my battery to see if that was the problem and it wasn’t.
If anyone can help, I would greatly appreciate it.
Im so lost because my 65 amp alt charges it’s just not big enough so I need to get this 100 amp to work. No fusible links are blown, I actually converted them to regular fuses. Im just so lost I have no idea what to do. The ground wire is new and runs straight to my battery to see if that was the problem and it wasn’t.
If anyone can help, I would greatly appreciate it.
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Cross-Country
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I’m not sure if this will help but here’s the new one I got.
https://www.summitracing.com/parts/s.../ford#overview
https://www.summitracing.com/parts/s.../ford#overview
Lead Driver
Joined: Nov 2006
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From: Pa.
I’m not sure if this will help but here’s the new one I got.
https://www.summitracing.com/parts/s.../ford#overview
https://www.summitracing.com/parts/s.../ford#overview
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From the description it says "no on 1 wire capable" and externally regulated. So It's definitely 1G. So from the 1G wiring diagram from above can you see any mistakrs in your current wiring set up ? Maybe tomorrow in the day light double check it. If still no joy post back and we'll go from there. A guy needs a 100 amps these days
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Make sure the voltage regulator is grounded good, after installing and removing the screws they get loose. It will blow the regulator if not, I went thru several before I was told to ground to the battery.
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However, I’ve got another question. With both the old and new alternator, there’s a 5th post on it with no writing next to it. With the 65 amp, the ground wire ran to that, leaving the post labeled “GRD” empty. With the new alternator, I moved the ground to the “GRD” post but it still didn’t change anything. What would be the reasoning behind that? Is that why the other posts on the alt aren’t getting power, because it’s not grounded properly?
Lead Driver
Joined: Nov 2006
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From: Pa.
The regulator has a good ground. The FLD post is still getting no power, and I checked the STA post and that’s not getting power either.
However, I’ve got another question. With both the old and new alternator, there’s a 5th post on it with no writing next to it. With the 65 amp, the ground wire ran to that, leaving the post labeled “GRD” empty. With the new alternator, I moved the ground to the “GRD” post but it still didn’t change anything. What would be the reasoning behind that? Is that why the other posts on the alt aren’t getting power, because it’s not grounded properly?
However, I’ve got another question. With both the old and new alternator, there’s a 5th post on it with no writing next to it. With the 65 amp, the ground wire ran to that, leaving the post labeled “GRD” empty. With the new alternator, I moved the ground to the “GRD” post but it still didn’t change anything. What would be the reasoning behind that? Is that why the other posts on the alt aren’t getting power, because it’s not grounded properly?
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Cross-Country
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This is the 65 amp but the 100 amp is identical. As you can see, the ground was not on the GRD post, but rather the empty post.
Lead Driver
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From: Pa.
This is the 65 amp but the 100 amp is identical. As you can see, the ground was not on the GRD post, but rather the empty post.
In the cab do you have a meter or a light for the charging system ?
Running ignition power to the "S" terminal of the regulator is the way the factory wired it when the truck had gauges and no dash light.
Dash warning light wiring =uses the "I" terminal and it must be hooked to a dash light and then key-on power. This brings the alternator online to charge.
The other way to hook it up leaves the "I" terminal blank, the "s" terminal on the alternator is blank, and the "s" terminal on the regulator goes to a key on power source. This brings the alternator "online" also to charge.
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I used to have the ammeter with my dash but now I have https://www.intellitronix.com/produc...placement-dash so its an electronic reading now.
So the main wire for the ammeter isn't hooked up. Could that be a potential problem?
So the main wire for the ammeter isn't hooked up. Could that be a potential problem?
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From: Pa.
I used to have the ammeter with my dash but now I have https://www.intellitronix.com/produc...placement-dash so its an electronic reading now.
So the main wire for the ammeter isn't hooked up. Could that be a potential problem?
So the main wire for the ammeter isn't hooked up. Could that be a potential problem?
Is it wired now where the gauge cluster is wired with the "I" blank, the "S" on the alternator blank, and the "S" on the reg wired to a key-on hot ?
Nice dash BTW !