I had a choice of bringing the Battery that I bought in September last year for a "load test". Or, buying a tester myself.
Or, buying another battery.
I decided to just try another battery.
It is getting the exact...and I mean exact, same result.
The engine groans a 1/4 turn and then stops.
As for voltage....
6.37v at Battery.
6.37v on one side of the (also new) starter switch.
4.51v on the other side of the switch when engaged. And ...
4.51v at the starter.
I'm at a loss.
This used to start better than my car.