gaffcat wrote:
I am building a boat and recently started my new Yamaha outboard for
the first time. While the engine was running I measured the voltage at
the battery and the reading was 15.5 volts. I have a 100 amp hour AGM
starting battery and the battery manufacturer reccommends a bulk
charge voltage of between 14.1 and 14.5 volts. Is there a way to
reduce the outboards charging voltage? Will this damage the battery?
I think the outboard puts out about 10 amps.

fritz

The voltage would probably drop as the battery became fully charged.