Catalina 320: Battery Voltage gauge showed the needle going past 16 volts

[Benny17441]

While the engine was running, I noticed that the battery-voltage gauge on the pod (measured in volts) showed the needle going past 16 volts. Does that mean I have a bad voltage regulator inside the alternator? Does that mean I'll have to replace the whole alternator? What are my options?

The engine is a Yanmar 3GM30F.

If you confirm that voltage reading reaching the batteries you definitely have a bad voltage regulator . Take the alternator to an automotive electric shop and you can get it fixed. Anything over 14.3 V would be suspect.