2017 Mercury Foursteoke 150

by Lane
(Fayetteville, NC )

I have a 2017 Mercury Fourstroke 150 and have had a problem with the alternator charging. It would run the battery down and then wouldnt start. I was getting 12 volts at the battery and at the post on the alternator while the engine was running. I have read some threads where people were haveing trouble with the alternator on these motors, so I replaced the alternator. I tested and was getting 21 volts at the alternator while running. Took the boat to the lake and had the same issue. By the end of the day, my Garmin was saying 11.3 volts. Engine would turn over twice and die. I cant find any info on why this would happen. I also noticed that my voltage guage never reads more than 12 volts. Any help would be greatly appreciated. I now have a new battery and new alternator, but still have an issue