Okay, so today I was on the phone talking to a co-worker who was helping me with some issues with my MS Office software, and we got on a discussion about boats. She used to work at the Marina and I asked her how the gas prices there compared to the ones here in town. She said they were very close, but the fuel at the marina has the oil additives needed for boat motors.<br /><br />This confused me. I have a sterndrive motor, Mercruiser Alpha One, and I check the oil in it before every trip. I fuel it up at the local gas station with regular unleaded fuel. Is there something I'm doing wrong here?