No battery charging with 6v generator

Tractor is a Ford 881 gas with 6 volt generator. There has been no charging at the battery via the generator for quite a while. The indicator on the dash stays lit while the engine is running showing no charging, which I further confirm with a volt meter at the battery (6.2 volts).
Today I polarized the generator and the light went out after starting suggesting it was now charging. I left tractor with it running for a few minutes and came back to find the indicator light back on. No charge at the battery with the meter. I shutdown and restarted the engine and the light stayed on. So I tried polarizing again. This time the light went out when restarting. It was running at about 1000 rpm for a few minutes. I reduced the engine speed to about 500 rpm, and the light came on. No charge at the battery (6.2 volts). I increased the engine speed back to 1000 rpm and higher, but the light just stayed on.
The battery was on a charger before this and so it should have been fully charged. It was 6.2 volts at the battery whether the indicator light was off or on.
I removed the generator and had it tested at a shop and it is working as it should.
Would a bad voltage regulator be causing this? It is a new regulator but been having this problem consistently.

THanks
 
How did you 'polarize' the VR? Did you get the battery tested at a trusty shop? Battery must meet specific gravity and maintain a full charge under load. Simply connecting a trickle charger won't do it. Did you motor test the GEN? The I&T F0-20 manual has a chapter on that. Or take the GEN and battery both to a trusty local shop to be tested -usually they don't charge for that. Get out you MPC and wiring diagrams and go thru entire electrical system. FINALLY, don't start replacing parts until old are proven defective.

Tim Daley(MI)
 
The charge indicator light is connected across the cut-out contacts. If it is lit, this tells you that the cut-out contacts are not closed & thus the generator armature (output) is not connected to the battery. Use a jumper to tie the ARM to BATT terminals together on the regulator, while engine is running at speed. Light will go out & at this point, measure battery voltage to see if it is rising.
 
JMOR,
When jumping the Bat to Arm on the regulator, the indicator light went out as you said. There was no change in the voltage reading at the battery; stayed at 6.2 volts. Wiring looks okay; couldn't find anything disconnected, loose, or broken.
 
(quoted from post at 17:30:31 03/08/22) JMOR,
When jumping the Bat to Arm on the regulator, the indicator light went out as you said. There was no change in the voltage reading at the battery; stayed at 6.2 volts. Wiring looks okay; couldn't find anything disconnected, loose, or broken.
ou can take one more step and jumper all 3 together (ARM, FIELD, BATTERY), then you will have forced cut out connection of ARM to BATT and full-fielded the generator. Only do while running & remove jumpers if stop engine.
 
JMOR,
I took your next step and jumped all 3 terminals at the regulator with the engine running. The voltage at the battery jumped to 7.4 volts, and continued to climb quickly. I disconnected when it got to about 8.5 volts, which it reached within about 30 seconds. The voltage did not stop climbing at that point, I just stopped the test there.
 
JMOR,
I took your next step and jumped all 3 terminals at the regulator with the engine running. The voltage at the battery jumped to 7.4 volts, and continued to climb quickly. I disconnected when it got to about 8.5 volts, which it reached within about 30 seconds. The voltage did not stop climbing at that point, I just stopped the test there.
 
That pretty well nails the regulator as the problem! It is good that you stopped, as under those conditions, there is no voltage or current control and if run like that for a long periods, the gen will overheat and battery could be harmed as well. Just good for a short diagnostic test.
 
JMOR,

This is fantastic help! A lot of the electrical comments on this forum can be confusing, especially to an electronics-handicapped person such as myself. This is the clearest and easiest description of what to do that I've seen.

Thanks a bunch!
Blair
 
(quoted from post at 18:16:51 03/08/22) JMOR,

This is fantastic help! A lot of the electrical comments on this forum can be confusing, especially to an electronics-handicapped person such as myself. This is the clearest and easiest description of what to do that I've seen.

Thanks a bunch!
Blair
lad to be of help.
 

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