Below a certain engine
size, outboards tended not to have a regulator
as the alternator
was considered too small to overcharge the battery
. I can't find data on the Hondas so I don't know about them. I'd be surprised though that an alternator
that small could drive a battery to that high of a voltage unless it was run a very long time.
Our club had chargers on small outboards, everyone was told never hook up the engine
without the battery, so of course it happened. I was wondering why several of the lights weren't working, and the bulbs all had a mirror coating. Without a battery in the circuit an alternater (without a regulator) will put out 50 or more volts. All the filaments had vaporized and redeposited on the glass. This happened enough years ago that the boats didn't have anything more sophisticated than light bulbs, now VHFs and knotmeters would hopefully blow fuses