New alternator, not charging

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Blackhatguy

Blackhatguy

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About a year ago the original alternator finally had the bearings let go, so I got a remanufactured one from advance Auto parts. It was working just fine, no problems with charging until the week before New Year's it's fried itself in spectacular fashion spitting pieces of copper all over my engine bay. Got the warranty replacement for it, and now I'm not getting any charge at all.

I am very much not good with electronics so I'm not sure where to look next, but I am wondering if the alternator going boom might have hurt anything else in line?
 
Blackhatguy said:
About a year ago the original alternator finally had the bearings let go, so I got a remanufactured one from advance Auto parts. It was working just fine, no problems with charging until the week before New Year's it's fried itself in spectacular fashion spitting pieces of copper all over my engine bay. Got the warranty replacement for it, and now I'm not getting any charge at all.

I am very much not good with electronics so I'm not sure where to look next, but I am wondering if the alternator going boom might have hurt anything else in line?
Click to expand...
Can you give us year make and model? Engine? If it's an early one, you were likely given a dual field alternator and one of the field spades needs to be grounded. More info would be helpful here.
 
It is a 1964 dart, originally slant and swapped for a 360. All accessories and alternator was from 1965 273 dart.
 
Generally I changed the voltage regulator something catastrophic happening with the alternator can take it out... Also it's only two bolts and a couple wires you can take it back out and most parts stores can bench test them...
 
As suggested, likely burned the VR OR THE wiring.

Disconnect field wires. Measure from big output post to ground. Should be "battery."

With alligator clip wires, or temporary ones with flag terminals crimped, connect to the field terminals. Hook one wire to battery and ground the other repeatedly while watching in subdued light. You should see (and maybe hear) a small spark. In any case, start engine with temp wires connected and see if it charges. If not try again monitoring output stud. If voltage rises way high, there's a problem in the charge path to the battery. If voltages stays "same as battery" the "new" alternator is bad

IF IT DOES charge

Now connect the blue field wire and with the remaining field terminal still grounded, it should now charge as well

If so.......disconnect VR connector and reconnect green field wire at alternator. Devise a way to ground the green terminal in the VR connector. Alternator should charge.

Make certain that WITH KEY ON "in run" that the blue at the VR connector has 12V If so replace VR.
 
Weather should be halfway decent tomorrow, assuming I can find my multimeter I'll give it a try after work and report back.
 
Blackhatguy said:
It is a 1964 dart, originally slant and swapped for a 360. All accessories and alternator was from 1965 273 dart.
Click to expand...
That doesn't matter. A LOT of these box stores will give you the dual field for a single field. If you have the big red hot wire and TWO additional spade plugs, that's what's happened. I would double check and make sure which alternator you have first and proceed from there, as Del described above. But doing all the tests in the world won't make that alternator charge if it is a dual field. The "other" spade terminal that's not being used has to be grounded.
 
Assuming your wiring is correct for a 65, you have a 1 field wire voltage regulator.
It should look like this.

Screenshot_20220215-222807.png


Your alternator origionally would have looked like this.

Screenshot_20220215-223045.png


The parts store replacement would have looked like this (most likely). Note the connector (blue arrow) is cut off. It is grounded to the frame of the alternator.

Screenshot_20220215-223357.png


If you were given an alternator that looks like this ( note both connectors are intact)
You might have the wrong alternator

Screenshot_20220215-223712.png


With an ohm meter you can test to see if the alternator you were given was an isolated field (2 field wires) or non isolated field (1 field wire) alternator

My bet though is the catastrophic failure of the alternator killed the voltage regulator
 
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In which case, I definitely have the correct alternator. When I find my multimeter I will do the tests that were mentioned, and inspect the voltage regulator

Dana67Dart said:
Assuming your wiring is correct for a 65, you have a 1 field wire voltage regulator.
It should look like this.

View attachment 1715870849

Your alternator origionally would have looked like this.

View attachment 1715870850

The parts store replacement would have looked like this (most likely) note the connector (blue arrow) is cut off. It is grounded to the frame of the alternator.

View attachment 1715870851

If you were given an alternator that looks like this ( note both connectors are intact)
You might have the wrong alternator

View attachment 1715870853

With an ohm meter you can test to see if the alternator you were given was an isolated field (2 field wires) or non isolated field (1 field wire) alternator

My bet though is the catastrophic failure of the alternator killed the voltage regulator
Click to expand...
 
Blackhatguy said:
In which case, I definitely have the correct alternator. When I find my multimeter I will do the tests that were mentioned, and inspect the voltage regulator
Click to expand...
In that case, I would proceed like Del outlined in post #7.
 
I actually replaced the one on my 64 Valiant with the dual field alternator on purpose. They normally charge better at idle, and it does. Sounds like you have other issues though.
 
Also on an original voltage regulator there are two fusible links. Take the cover off and look.
 
To Matt's point...
One or both of the two wires will fry if shorted to ground.
16450224409108801904817791611019.jpg
 
Blackhatguy said:
It is a 1964 dart, originally slant and swapped for a 360. All accessories and alternator was from 1965 273 dart.
Click to expand...

Well I see THIS has completely morphed, which is why it is very important to mention these little tidbits..............

As others have said..............
Simply disconnect the alternator and alligator clip------jump battery to the field connector. If it does not charge..........Look to see if there is a SECOND field connector on the alternator--------you must ground that

BUT BE CAREFUL If they gave you an alternator with two field connectors, which is for 70/ later, you must ground one of them, BUT BE CAREFUL!! Check that one is not already grounded!!! You don't want to connect to the terminal which is already grounded.

Once you get that problem solved, reconnect your green wire and see if it charges. If not, you have likely damaged the VR

SUMMARY:
1...The new alternator can be defective
2....The VR can be defective
3....Some sort of wiring problem
4.....The new alternator may be "isolated field" incorrectly called "dual field"
5.....The new alternator, if isolated field, may be grounded, and if you connected field to grounded terminal, you have now damaged VR
6......The new alternator may NOT have one field terminal grounded, so which you need to ground it
 
I verified the alternator is correct single field, everything is hooked up correctly. Also it turns out that the voltage regulator is an electronic version, looks just like the original from the outside but when I pop the cover off it has a chip board full of little transistor looking things. I do not have a test light or a multimeter right now to do the tests y'all gave me, but I have ordered one and some wire and alligator clips to make jumpers. I will update after that.
 
OK I missed that.

You can do some intelligent guessing. Jumper the two wires that connect to the VR together. This will put "full battery" onto the field from the blue IGN wire. Start, run, see if it charges and it will OVER charge if you rev it up. If it does that---tells you the alternator and field wiring--and the charge wire path--are all OK, and that likely you need a VR. Make CERTAIN the VR is grounded
 
Blackhatguy said:
Also it turns out that the voltage regulator is an electronic version
Click to expand...
Electronic versions of single wire field VR can / will fry if shorted to ground.

Do as 67dart273 said to prove out the wiring and alternator is good.
 
I want to thank everybody deeply for the help, I am not an electrician by any stretch of the imagination so it was extremely helpful to have the diagram and step by step tests to run. That being said, everything upstream and downstream of the voltage regulator is working exactly as it should, so it's just the electronic voltage regulator itself appears to be fried.

Any suggestions on a quality replacement?
 
Blackhatguy said:
Any suggestions on a quality replacement
Click to expand...
They make old style electromechanical and electronic that look like the old style.

You will know the difference by the underside, old style will have the resisters under it.
 
Dana67Dart said:
They make old style electromechanical and electronic that look like the old style.

You will know the difference by the underside, old style will have the resisters under it.
Click to expand...
At almost every turn I prefer the idea of mechanical over electronic, but I have heard that the new ones aren't built as well. Unless you have one you trust?
 
I'm 73 so I'm well acquainted with mechanical regulators, both DC generator and alternators. A well made solid state VR is eons more reliable than a mechanical. Bear in mind that if you were to find a "modern" made mechanical, it would very likely suffer the same quality control issues of the electronic ones.

Only suggestion I can make is look for a "new old stock" on ebay, either Standard/ Blue Streak, Echlin, or the Chrysler "blue" regulator (So called "race", constant voltage, Mopar Performance, etc)
 
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