RedactedNarrative: The operator fueled up at Harbor Light Marina at approximately 1030 hours. After fueling up the vessel he left the marina at idle speed. The operator advised me that he cut his blower on after fueling up and cranking up the vessel. The blower was only on approximately 10-15 seconds before an explosion occurred. After the explosion the operator tried to extinguish the fire but was unable to do so. The operator jumped over board due to the flames getting higher. He was picked up by other boaters that had seen the incident. The vessel drifted towards the main body of the Lake with a fully involved fire and sunk as a result of the fire. The operator was not injured as a result of this incident.