[T3] I don't know why yet for some reason my 73 T3 charging system seems off.

[Sean Bartnik]

Very simply, the generator doesn't do much at idle. It can't produce a lot of current at idle speed. So the electrical draw of the car outstrips the generator's ability to keep up and the battery begins draining - which is the slow voltage dropping that you see. 

If your battery is coming down to 12.6v after the surface charge dissipates, it is fully charged. 

-Sean

> On Jun 29, 2017, at 4:17 PM, William J <catnine09 at dslextreme.com> wrote:
> 
>  What I just can't get is why will idling in drive at 800 engine RPM why does the voltage drop from 14.1 to 13.5 then 12.45 volts ?