check the bulb first! Mine was blown. Both Brake and Gen light should come on with the key.

The GEN light is a very simple circuit. It starts at the key switch, feeds the light bulb and continues to the 'ARM' lug on your voltage regulator. That bulb socket is NOT grounded and it has two wires in the back.

Better revisit your bulb again. It should come on with the key turned to the 'on' position and its purpose is to send current straight through your armature, through the brushes and out to ground. When the bulb shines, it IS flashing your armature, so no need to do it again. If the bulb is good and it does NOT shine, check your generator's brushes.

In vehicles and tractors with no GEN light, the voltage regulator resistors should pass enough current to energize the 'cutout relay'. Sometimes those resistors break because they are so brittle (and old) with lots of heat/cold cycles.

Notice that the 'voltage' and 'current' relay contacts are normally closed. They also need to be CLEAN. Run some fine sandpaper through the contacts to knock off any oxidation. It's best to do this without disturbing the mount. In other words, leave the VR on your fender apron so you don't touch the resistors in the back.

The VR needs a good ground and it should have a capacitor mounted to it. The cap is the same as your points condenser (.22-uf) and it 'cushions' the electrical noise created by the VR contacts. - Dave

It was a loose bulb in the socket.

Thanks!

Do yourself a favor, John. Replace with a new #57 bulb if that one is old. You see how important that little 'idiot light' really is. - Dave

I love it when a plan comes together