"relatively anemic producers "
Just to tag on to the previous post ... the "alternator" in an OB is designed to trickle charge back in the minimal amount of power it consumes when started. It doesn't (at least on my Honda 9.9) have the power generating capacity to bring back up a starting battery and a house battery that have been deeply discharged by, say, a weekend of sailing or hanging on a hook. AT LEAST VERY QUICKLY. Run the thing for a couple hours and you'll make some progress. If you run it for 10 minutes out and 10 minutes back in, your batteries will slowly drop down.Tom MonroeCarlyle Lake