"Carl" wrote in news:1151090387.562299.34550
@u72g2000cwu.googlegroups.com:

Thanks for all the replies which collectively are very helpful. I
didn't make it clear in my original posting that the outboard does have
an electric start so I suppose that it does act as an "earth" - but
presumably only whilst it is in the water. When sailing or at the dock
the outboard is raised. My problem is getting my head around the
concept of grounding connections on a boat (as opposed to land-based
earth connections or vehicle grounds) - but, if I read your replies
correctly, it seems that it is not that important.
Thanks again, everyone.




The outboard's starting battery isn't connected, or shouldn't be connected
to the AC charger for the house batteries....so there's no reason at all to
"ground" it to the AC line, opening it up to awful electrolysis currents
from all the crap on the docks. I'd want to insure it was fully isolated,
myself. I hate changing zincs.