One a dual field alternator, would it still function the same if the two wires were swapped on the field connections?
Alternator field wires
- Thread starter MoparMike1974
- Start date
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Stanley Blake
Well-Known Member
Don’t no if will will work, but the green wire connects at the 11 o’clock position and the blue wire connects at the 9 o’clock position.
Ok, im having an over-charging issue and wanted to make sure this couldnt be the problem.
67Dart273
Well-Known Member
OK, do a "few things." Ground one field terminal with a clip wire, then connect the blue. This should cause the alternator to charge full output. Make certain with the key on, that you are getting battery to the blue wire, and that the field is actually drawing current. One easy way is to turn key to run, and in subdued light, connect/ disconnect the blue field. You should see a small spark when doing so. Alternatively you can measure current with a meter. The field should draw +/- 4A or so
If that is ok and it does not charge, measure at the alternator output stud while running fast idle. If that terminal is way high, and the battery is low, then you have an open in the charge wire/ path to the battery
If that is ok and it does not charge, measure at the alternator output stud while running fast idle. If that terminal is way high, and the battery is low, then you have an open in the charge wire/ path to the battery
Its charging just fine. The problem is its over-charging. Its pegging the amp meter, going full charge. The blue field wire has full battery voltage when the key is on. Its within a tenth or two of a volt compared to the battery. I added a ground wire to the votage regulator today but have not tested yet.
67Dart273
Well-Known Member
Sorry "the old man" misread. OK first unhook the green wire at the alternator and see if it stops charging. If not, that field terminal is grounded. Then reconnect it and unhook the VR plug. It should of course not charge. This will tell you if the green wire is shorted/ grounded, which is rare but does happen
Then make DARN sure the VR is grounded. Clean around the bolt holes, etc and remount. "Work" the connector in/out several times to scrub clean.
If that does not get anywhere, I'd guess the VR is bad
Then make DARN sure the VR is grounded. Clean around the bolt holes, etc and remount. "Work" the connector in/out several times to scrub clean.
If that does not get anywhere, I'd guess the VR is bad
Test as 67Dart273 said.
The blue wire is the sense wire for the regulator. The vltage there determines what the regulator does.
It also is the feed wire for the field circuit.
Since you have a multimeter, check the voltage while running.
Check it at the battery, the blue wire, and at the alternator output stud. Note the rpm (fast idle or slow). Then shut it off!
PS. There is only one field. It's the magnetic field generated by the current through the rotor.
The reason for two terminals is the way the regulator works.
Earlier regulators controlled the feed current so the second brush was just grounded to the alternator housing.
The newer regulators work like this.
The reason for two terminals is the way the regulator works.
Earlier regulators controlled the feed current so the second brush was just grounded to the alternator housing.
The newer regulators work like this.
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I swapped out two other regulators and grounded them directly to the battery. It stops charging when you disconnect the VR plug. I have not checked the running voltage on the blue field yet.
Engine harness is all new but has been modified. I removed the ballast resistor, and original ecu wiring. Integrated in my MSD fuel injection and MSD 6AL wiring. Run 1 & 2 are tied together and feed the blue field. So im thinking maybe the load on the run wire is too great. Its only switching on the 6AL and Atomic EFI which both have large gauge wires going straight to the battery so they should be on relays internally.
Engine harness is all new but has been modified. I removed the ballast resistor, and original ecu wiring. Integrated in my MSD fuel injection and MSD 6AL wiring. Run 1 & 2 are tied together and feed the blue field. So im thinking maybe the load on the run wire is too great. Its only switching on the 6AL and Atomic EFI which both have large gauge wires going straight to the battery so they should be on relays internally.
here's why I suggested that in addition to 67Dart273's test.
One reason the battery could be drawing over 40 amps is the alternator is producing power at a voltage above 15V.
The other reason could be that the battery is very low on charge and the alternator is producing power between 13 and 15 V.
see posts 11-13 in this thread about how a battery draws
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Because its an open circuit.
Look at the above diagram.
While idling at 800 rpm I have 12.2v at the battery and 11.8v at the blue field on alt. I jumped 12v from the battery directly to the blue field and it continued to charge full steam. Swapped out a couple other used voltage regulators (unknown condition) and it did stop charging and after running a while it started charging again but again at full rate pegging the needle. When it was kinda working it was not charging at all. I turned on the blower motor on high and the amp meter needle dropped way down and no charge.
I had a big pile of used regulators from parts car but the potting melted and turned them into a big blob of crap. So I only have three to work with and one is confirmed bad. I have a brand new one around here somewhere but have not been able to locate it yet. Getting ready to start testing these used ones on my other dart to weed out the good and bad for sure.
I had a big pile of used regulators from parts car but the potting melted and turned them into a big blob of crap. So I only have three to work with and one is confirmed bad. I have a brand new one around here somewhere but have not been able to locate it yet. Getting ready to start testing these used ones on my other dart to weed out the good and bad for sure.
You're making us read between the lines here.
If doing so correctly..
Test 1.
Engine running 800 rpm
12.2 V at Battery
11.8 V at Blue wire on field terminal
ammeter showing 40 amps charge ???????
If so this would indicate a dead battery or equipment wired to the battery.
Test 2.
Engine running 800 rpm
??? V at Battery
??? V at Blue wire on field terminal
Ammeter showing 40 amps charge
I'm guessing this was a test to eliminate possible voltage drops.
It halfway did that.
There still could be drop between the alternator and the main splice.
Better to three test points suggested in my earlier post. That plus the ammeter reading should reveal the issue.
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Aw sh*t. How much is the EFI drawing? The 6AL is 1 amp/1000 rpm so that's nothing assuming its working right.
If you want to use an ammeter with EFI and electric fuel pumps, connect them on the alternator feed.
The way you have it, with the EFI and MSD connected at the battery the ammeter is showing the current to charge the battery and those additional items.
At best, the battery can supply power at 12.8 V.
As soon as the alternator is producing power at a voltage higher than that, it becomes the source of power. Power always flows from the highest voltage source. the ammeter shows that current flow.
You got this.
the meter shows flow through to everything to the left of it.
For the ammeter to show only battery charging, the additional stuff has to be wired somewhere on the alternator side. Like this
That also keeps those additonal loads off the bulkhead connector, except when starting or if the alternator dies.
The way you have it, with the EFI and MSD connected at the battery the ammeter is showing the current to charge the battery and those additional items.
At best, the battery can supply power at 12.8 V.
As soon as the alternator is producing power at a voltage higher than that, it becomes the source of power. Power always flows from the highest voltage source. the ammeter shows that current flow.
You got this.
the meter shows flow through to everything to the left of it.
For the ammeter to show only battery charging, the additional stuff has to be wired somewhere on the alternator side. Like this
That also keeps those additonal loads off the bulkhead connector, except when starting or if the alternator dies.
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Once you solve the problem, consider doing like was done by Chrysler for 60 amp and other higher output alternators.
One version is something like this
and another something like this
One version is something like this
and another something like this
Hey guys, its going to be a bit before I can get back on this issue. Had a tree fall yesterday and knocked out my power. Second one in a month. Also going to be real buy at work for several days so back burner for this one. In the mean time I went ahead and ordered a couple new voltage regulators to have on hand. Had a new one here but damn if I can find it.
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