Overcharged Battery- 16v. Generator won’t start

[BeneG]

Hello All,

On a charter boat and trying to troubleshoot an issue. I know they have engineers to talk to, but they are now closed and I’d like to learn more about the issue to be better prepared in any similar situations in the future- and to know what to avoid had the fault been with me.

Sailed for a big part of the day out in the Caribbean and all was going smoothly until the end of the day when we anchored and went to turn on the generator( which we are using for our AC). I jumped down into the generator space, pushed the genset battery switch, it started up the digital screen and I started it as instructed. The generator stated as it had the past few times, but after about an hour, we got an alarm reading that a battery was at 16v. I quickly turned off the generator assuming that a battery was being overcharged by the generators alternator. We checked a few things and decided to turn on the generator again to see if it was went back to working normally, yet now the digital screen to start the generator would start, but as soon as I let go of the genset battery switch it shut off and the generator would not turn on.
I assume the generator starter battery had been overcharged and is now not working properly, but I wondering if it might be something else that is more easily fixed? The boat is newer and fitted with more high tech systems than I am accustomed to.

Let me know if you have any thoughts? Where I’ve landed is that it might be something with the alternator/ regulator?

Thanks in advance!
BeneG

[Lepke]

The start switch bypasses a safety circuit That usually includes oil pressure, coolant temp, exhaust temp, and apparently in your case the battery voltage or temp. While the switch is depressed, the sensors are offline. When you release, a low oil pressure, over temp, etc. will stop the generator.

A guess would be the regulator is bad. It's not your boat and any damage you'd have to pay for. So disconnecting the alternator could be bad advice. But disconnecting all the alternator wiring, the heavy, usually red wire, going to the battery and plugs or smaller connections should allow the alternator to run w/o harm and no longer charge. Keep the connection ends from touching anything metal.If it's a diesel engine it only needs minimal power for any gauges. A gas engine needs ignition and should last a long time, but if you run the battery all the way down you'll need to charge or jump it. You might be able to run several hours, shut down, hook everything back up and run until the battery is getting overcharged.