Yes, it is called a voltage regulator. They go bad from time to time. Tend
to be more of a problem on OMC than Merc or Yamaha. You need to replace it
before you burn up another battery.

--
Tony
My boats and autos - http://t.thomas.home.mchsi.com



"Jack Goff" wrote in message
m...
1999 Johnson 150 carb outboard. Put in a new battery last summer.
Voltmeter normally shows 14-16 volts and has since new. Couple weeks ago
I
went for a short run (it stays in the water year-round), and I noticed the
voltmeter was showing nearly 18 volts. Turned on the running and dock
lights, but it stayed there at about 3k rpm. Not until I got back to the
no-wake did it drop back to 14 or so. It cranked up just fine, no
dragging
like the battery is going bad again.

I've read all about the terrible charging circuits outboards have in them.
There doesn't seem to be much of a regulator in there, but 18 volts is way
too much, and a change from what I'm used to seeing. Any ideas? Is this
a
known fault that outboards, or Johnsons develop?

Thanks...

Jack