How i do i write this as briefly as possible? I wish i knew.
My alternator simply refuses to charge. It'll keep the battery around 12.6 volts with no accessories on :/
The original alternator if i recall right did at one time output around 13.7 volts back it was being driven heavily in summer 2016.
Well, that was back when i didnt lose the only set of keys like a moron and didn't have to hotwire it,which it now is...
Fast forward to 2018 and the battery doesn't charge as stated before, 12.6 volts when running. I can unplug the battery and charge it overnight with an external battery charger, itll test to around 12.8v, and as soon i try running the car she starts to drain.
In November 2016 the alternator belt had snapped, but was replaced in February 2017 i'll add.
I don't believe its my hotwiring job,nor the belt because prior to it being towed to my new place in August 2017, it was able to drive down the alleyway ok. Now she barely wants to move and runs hella sluggish, in fact when i put her in drive she struggles more.
Heres what I've done so far for diagnosing:
1.Checked with a meter battery voltages when off and running (never goes past 12 volts)
2. Checked alternator with a meter when running, still reads an output that the battery does, 12ish volts.
3. Replaced the original alternator with 2 different ones, same no charging results.
4. Used original wire connector for alternator with same results.
5. Hacked off original wire connector and wired on the ones that came plugged in the replacement alternators, same result.
6. Removed neg bat cable while running after 1st alt replacement- car doesnt die but lights were VERY dim in dash. Meter measured 7 volts.
I should mention with the original alternator and 1st replacement, my charge light would normally turn on as normal when accesories
were applied, and turn off after the engine was running. However, the 2nd alternator which i tried installing today, it now keeps the charging light CONSTANTLY illuminated even when running now, with occasional flickering of the charge light. Giving the engine a good rev doesnt help.
Voltage regulators are internal on the 12si alternator, so i dont see externally a problem there.
And both of the 2 alternator swaps yielded same voltages (however the 2nd swap now gives me a charge light when running too now, the other original and 1st swap only did when it wasn't),. Both are original Delco Remy parts pulled from cutlasses...
Could it be a partially burned fusible link? I can put my meter on the alt and itll match the battery voltage wise.
Could it be a bad fuse in the fuse box? I don't recall having an alternator fuse....
I will mention i wired up an aftermarket stereo as well, but i have the unit unplugged at the moment for testing.
I'm REALLY tempted to just directly wire the battery to the alternator and skip the wiring harness, but it needs to be fused and i have no idea how to begin with that.
If i gotta replace the alternator a 3rd time, i'm sure the junkyard will do one more warranty replacement, but i'm hoping someone can tell me how to test the alternator so i know its good this time before i spend the day to cross the city and take it on the train home....
Hopefully someone can give me some insight here, cheers!
-Chris
My alternator simply refuses to charge. It'll keep the battery around 12.6 volts with no accessories on :/
The original alternator if i recall right did at one time output around 13.7 volts back it was being driven heavily in summer 2016.
Well, that was back when i didnt lose the only set of keys like a moron and didn't have to hotwire it,which it now is...
Fast forward to 2018 and the battery doesn't charge as stated before, 12.6 volts when running. I can unplug the battery and charge it overnight with an external battery charger, itll test to around 12.8v, and as soon i try running the car she starts to drain.
In November 2016 the alternator belt had snapped, but was replaced in February 2017 i'll add.
I don't believe its my hotwiring job,nor the belt because prior to it being towed to my new place in August 2017, it was able to drive down the alleyway ok. Now she barely wants to move and runs hella sluggish, in fact when i put her in drive she struggles more.
Heres what I've done so far for diagnosing:
1.Checked with a meter battery voltages when off and running (never goes past 12 volts)
2. Checked alternator with a meter when running, still reads an output that the battery does, 12ish volts.
3. Replaced the original alternator with 2 different ones, same no charging results.
4. Used original wire connector for alternator with same results.
5. Hacked off original wire connector and wired on the ones that came plugged in the replacement alternators, same result.
6. Removed neg bat cable while running after 1st alt replacement- car doesnt die but lights were VERY dim in dash. Meter measured 7 volts.
I should mention with the original alternator and 1st replacement, my charge light would normally turn on as normal when accesories
were applied, and turn off after the engine was running. However, the 2nd alternator which i tried installing today, it now keeps the charging light CONSTANTLY illuminated even when running now, with occasional flickering of the charge light. Giving the engine a good rev doesnt help.
Voltage regulators are internal on the 12si alternator, so i dont see externally a problem there.
And both of the 2 alternator swaps yielded same voltages (however the 2nd swap now gives me a charge light when running too now, the other original and 1st swap only did when it wasn't),. Both are original Delco Remy parts pulled from cutlasses...
Could it be a partially burned fusible link? I can put my meter on the alt and itll match the battery voltage wise.
Could it be a bad fuse in the fuse box? I don't recall having an alternator fuse....
I will mention i wired up an aftermarket stereo as well, but i have the unit unplugged at the moment for testing.
I'm REALLY tempted to just directly wire the battery to the alternator and skip the wiring harness, but it needs to be fused and i have no idea how to begin with that.
If i gotta replace the alternator a 3rd time, i'm sure the junkyard will do one more warranty replacement, but i'm hoping someone can tell me how to test the alternator so i know its good this time before i spend the day to cross the city and take it on the train home....
Hopefully someone can give me some insight here, cheers!
-Chris
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