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I am still confused why I show the generator producing 10 AMPS charging on the ammeter yet the battery is not charging and the voltage is only rising a few tenths of a volt while the charging rate goes from 0 to 10 AMPs charging.

I wouldn't discount the battery as being the source of the problem. Earlier I advised to substitute a known good battery and re-evaluate the situation. I have no personal experience with gel batteries like Optima, I have had nothing but great success with the large lead/acid batteries like the NAPA 7212 or Delco 4HD6V in senior Packards with underseat or fender-mounted batteries. Friends that use gel batteries have had experiences with them ranging from euphoric to problematic.

I had similar experience with a 12v optima that bit the dust. The charger stayed on all night, said it was charging but next day battery still did not have the oomph to crank very slowly for more than a few seconds.

I don't think the battery is the problem as putting a charger on it for a few hours and it was good. Also charging the battery with a jumper cable work fine. What appears not to be working is the battery is not charging via the generator.

Also sometimes if the battery is totally discharged, the battery charger won't detect a voltage and won't charge. I had that happen recently wit a newer car. I first jumped the battery with cables. Then I put the charger on it and it charged.

What appears not to be working is the battery is not charging via the generator.

That's not consistent with your observation that it is receiving a 10 amp charge. Again, the 10 amp charge is consistent with the 3rd brush at its minimum setting. Set the 3rd brush to a higher charging rate. IIRC correctly turning the fillister-head screw clockwise increases the charge rate.

What happened to the charge rate when you grounded the field wire?

When I asked before I believe you said your generator was a "1002"; no such Dyneto generator that I know of. Want to look again - it should be a Cl-1005?

How sure are you of the amp meter? Ten amps may not be 10. If you have another good meter then I would suggest putting it in line with the existing meter.

The easiest way to do that is to put a meter in series with the battery. Make sure you have a meter that reads in the range you are looking for in this case 10a. I used one that had a first reading of 35a which was almost useless

Still waiting to hear what happened when you temporarily grounded the field wire. And here's two other thoughts to think about.

(1) Unless you have an extreme diet of short 2 or 3 mile drives between starts or constantly use a vintage vacuum tube radio which draws large amount of current, a 10 amp charging rate is more than adequate for daytime driving to keep a battery fully charged. I keep my 34 rate at about 7 amps for daytime driving and increase it via the 3rd brush if I'm driving at night. The only time I use a battery charger is after winter layup.

(2) Yes, using a 2nd ammeter to validate the reading of the car's ammeter is a good idea. But not in series with the battery cable!! Those Dyneto starter motors can draw 250-500 amps so if you use a meter with that +/- range, you won't be able to differentiate 10 from 20 amps and if you use a meter with a smaller range you cook it to toast. Either put a +/- 30 amp meter in series with the existing dash meter, or in series with the main body/chassis feed which is taken from the starter relay, or better yet, right at the generator output from the regulator. In addition to ammeters with direct connections on the back, there are also meters which simply lay across the wire and use the magnetic flux to indicate current direction and amperage.

I just decided to pull the generator. It hadn't been touched since I owned the car so I wanted to get it serviced. Plus it looked like it needed it.

I'm pretty confident of the ammeter as it was restored about 5 years ago by a reputable instrumentation person.

The generator is model 1005. I was trying to read it before with a mirror. Easier to read now that the generator is out.

I'll let you know what the results are once I get the generator back and installed.