I have a 48 8N with a 3 brush generator, positive ground, A-circuit.
Here's the short version:
I rewired the electrical system, installed a new regulator, and had the generator checked. After all this, the battery (less than 1 year old) charged perfectly. Fast forward two weeks and I notice that the ammeter stays at zero. Sure enough, it's not charging.
I have done the following troubleshooting:
1. Disconnected the generator and measured the output. It's around 20 Vdc.
2. Shorted the field to ground. This causes the Generator to produce current in proportion to the RPM.
3. Removed the regulator cap to observe relays. I found that the field relay (not sure if this is the cutout relay) I noticed that the when the contact is made, the system charges. As RPMs build, the magnetic field in that coil strengthens and opens the contacts. This causes all charging to stop.
Remember, this is a brand new regulator. At this point, I'm not sure what I'm looking for. I am researching the function of the second relay.
I just done want to throw in another regulator without understanding what is causing this one to act up.