I have had the SAME PROBLEM every year since my 1999 Four Winns I/O was new--it will start up just fine and run great for two or three runs. We stop to eat lunch for an hour, and it won't start--it cranks but won't fire. Changed the fuel filter, added gas, checked the wiring, checked the kill switch. It won't go. We let it sit overnight and it still won't start today. Of course we're on vacation and have company at the lake, so it's the absolute worst time! Any ideas? The guy at the local marina was guessing it might be the fuel pump. I even tried starting it with the throttle down but it just won't fire.