I have twin 350 1990 mercruiser engines. I winterized both last year darined all water from everything hoses, block, risers manifolds anyway one engine is ok the other has about 1/2 quart of water in the oil pan. I drained it out with a suction tube. I left my boat in the water all winter and the marina bubbles the water when the temp drops. Where the heck did this water come from? and what should I do now? One Last thing. when I fogged that engine and had my wife turn the key off and the engine spit a sputtered for about 5 seconds. I heard that can cause water to be sucked back up in somewhere. Just wanted to let you know that.