It just gets "curiouser and curiouser"... This is a follow-up to my previous posting:
https://www.fordbarn.com/forum/showthread.php?t=330390
O.K. I finally got some free time, so I spent the last 1 1/2 hours switching generators and cutouts around in an effort to find the cause of the no-charging issue in this rebuilt generator. Briefly, I checked this generator and a known good generator with four cutouts: three Nu-Rex electronic positive ground cutouts (numbered 1-3 for my tests) and one original points cutout (numbered #4). The known good generator showed a charge with all four cutouts, which is the good news. The issue is therefore not cutout related. That's a relief.
I put the generator in question back on the engine and tried all three electronic cutouts. No charge. Putting on #4 original cutout, the ammeter registered a charge. I then took the generator apart, looking for frayed wires or bare wires touching the steel case. Nothing. Re-assembling it, I tried #4 cutout again and the generator charged, as before. But NONE of the electronic cutouts charged, although all three worked on the other generator. Strike three.
Then something curious happened. I took the fan belt off the generator pulley and ran jumper cables from the battery to test for "motoring". The generator motored very well, but it spun in the wrong direction! I removed the cables and hooked them up to the known good generator. Viola! It turned in the correct direction. And then something even more curious happened. I connected the jumper cables to the questionable generator again (still on the engine) to double-check the spin direction. Still the wrong way. But...as I removed the hot lead and momentarily left the ground cable attached to the generator case, the armature continued to motor, albeit slower. What the heck is going on here??? It should not motor at all with only one jumper cable connected, especially the ground jumper cable, not the hot lead.
The package containing the new field coils was clearly marked for a six-volt system and when the generator was tested with my six-volt battery, it turned over rather quickly for a generator compared to a starter. So, I'm confident that the field coils are not 12-volt. Same with the armature. But what would make the armature turn in the wrong direction with all new parts and why would an original cutout produce a charge in this condition, but not the electronic ones? I can only assume that the flow of current is going in the wrong direction to make the electronic cutouts kick in, but the original points cutout doesn't care one way or another.
So, why does this generator motor in the wrong direction? That has got to be the cause of this generator's non-charging issue with electronic cutouts. I am not an electrical guru enough yet to figure this one out on my own and the Model A generator-starter booklet does not give a cause for this in the trouble-shooting section.
Ideas???
Marshall, the Electrically-Challenged One