RedactedNarrative: THIS IS A 1 VESSEL ACCIDENT. OPERATOR & PASSENGER WERE ATTEMPTING TO GET THE PWC BACK TO BOAT RAMP AT WATERFRONT MARINA. THE VESSEL KEPT CUTTING OFF. THEY WERE USING A BATTERY BOX TO "BUMP START" THE VESSEL BECAUSE THE BATTERY DID NOT HAVE ENOUGH CHARGE TO CRANK. AFTER SEVERAL ATTEMPTS TO START THE VESSEL THE ENGINE BACK FIRED CAUSING A FIRE IN THE ENGINE COMPARTMENT. VESSEL OCCUPANTS WERE ABLE TO GET OFF THE VESSEL WITHOUT INJURY. SOMEONE CAME ALONG BESIDE THE PWC AND EXTINGUISHED THE FIRE. THE LOCAL FIRE DEPARTMENT ALSO CAME ON THE SCENE.