Two of my jobs when we return to the dock are to: 1-close the engine through hull and 2-put the engine battery key away. When we were getting ready to leave the dock yesterday to anchor overnight I turned the engine through hull handle to open it but I couldn’t find the engine battery key. Huh. It was still in its keyhole from our brief daysail the day before. We finished getting ready and left the dock. About 100 feet away from the dock I noticed that the engine didn’t sound right. It occurred to me that instead of opening the through hull I had closed it. I put the throttle in neutral, asked George to take the helm, and rushed down to the cabin to check. Sure enough, the through hull was closed. I opened it, we carried on, and the engine was soon spitting out engine cooling water as it should. Phew. Crisis averted, we hoped. The engine through hull allows seawater to be drawn into the engine to cool it. Without it the engine overheats. As it overheats the impeller, the little rubber ...