72 Swinger not charging battery

scudzuki said

The blue wire goes to the VR. It is switched 12V so it is not directly from the battery. It is not full battery voltage due to resistance in the wiring. I did read your full post. I may be wrong about the 8V, it could be higher than that, but it was not the same as the battery voltage, I'm sure of that. If it's lower than the actual battery voltage, the field would be excited more by the VR, so with a working VR, the charging voltage should be even higher. I've been on and off this thing between working my real job. Thanks for your contribution and enjoy your 4th

Click to expand...

You still have it wrong. First I never said the blue came from the battery. I actually SAID it was switched 12V. I know ALL ABOUT harness drop, and all I can do is go by what you said, which is 8V

THE VR DOES NOT EXCITE THE FIELD. It merely controls the field current from the source, AKA the blue from the switch.

WHAT CAUSES OVER VOLTAGE from the VR circuit is the voltage drop in the blue "run" circuit as seen AT THE VR. That is because the voltage drop makes the VR "think" that voltage is low, so it ramps up field current. This problem is NOT caused by the field circuit. It is caused completely by voltage drop in the ammeter, the bulkhead, and the "ignition run" feed circuit, and culminates AT THE VR ign/ power terminal

One way to address this drop is to cut the blue ign "run" lead coming out of the bulkhead, electrically. Run the bulkhead end to trigger a relay, and connect the engine bay end to the switched contact. Feed the power contact from say, the start relay with no12 and a fuse or breaker.