First off, I was underway and cruising at approx 4500rpm when the motor lost power and slowed to a stop then cut off immediately. I then let it set for 10 minutes and tried to start and as I turned the key all of the gauges/fish finder/gps would cut out and motor would not turn over. Maybe a coincidence but I turned battery switch to all and then it started. Motor sounded fine but as I got on plane and cruised at 3000rpm for 10 minutes it started to make a rattling noise and I slowed it to idle speed and limped back to dock. Anyone have any suggestions on where to begin? I haven't tried to start it for the last couple of days but was going to inspect spark plugs then do a compression check. Could it have been a dead battery while underway? Any info will be appreciated. Thanks