I have a 1986 Regal Sebring with a Mercruiser 170hp motor. My gauge for my battery is just a tick above complete 0. I can run the boat fine with no issues for approxiametly 6 uses. I noticed that when i push the button for the trim the battery gauge dips even lower. After the 6 uses the battery usually dies. I replaced the battery with a new one and still the same results. I then put an ohm meter on the battery while the boat was running and it displayed a lower then optimum reading. I looked to see if I could see an alternator on my boat but it appears I do not have an alternator. I believe it is a magneto of sorts. Any help or suggestions would be appreciated.