You'll need at least 13 volts, minimum, even with the accessories on. The normal regulated voltage against a fully-charged battery will be about 14.5 or slightly more. Anything below 13 at as fast idle probably means you're running off the battery, not the generator. Did you try cleaning the regulator points as I suggested, using a piece of file card or something similar?
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
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