I wasted several billion electrons with a long reply to this thread, and the internet gremlin ate it when I hit "Post"! Before you do anything else- - - -polarize the generator. Use a short jumper wire to connect the BAT and ARM terminals of the regulator together momentarily. You'll get a pretty good flash, which is normal. 1/2 second or so is plenty. That wakes up the residual magnetism in the generator housing and makes it capable of flowing current in the field coil windings. Even a brand new generator won't charge unless it's polarized first. Engine running or stopped doesn't matter. Then measure the battery terminal voltage with the engine running at fast idle. Look up the tutorial I wrote several years ago in the Tech Tips area "6 Volt DC Charging systems". Most of that info also applies to 12V systems. No, I never got around to finishing the series of articles I had planned to do!

www.stovebolt.com/techtips/6v_charge_system/index.htm

Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!