I had water in cylinders on my marine power 454 on   2 trips in a row. I got some advice to increase my idle speed to 1000 from member GT. I set it to 1100 and had a trouble free weekend at lake Mojave. Time will tell if my troubles are over but lt sure seems better. I appreciate the advice. I have a 427 corvette that runs great at 650 idle but it just goes to show that sometimes you just don't know what you don't know. Thanks again to GT and others that responded to my message.