RedactedNarrative: On August 20, 2013, I (CPO) was notified of a boat fire on Fox Lake in the area of Columbia Bay approximately 600 yards west/north west of Electric Harbor in Lake Villa.  I contacted Electric Harbor and told them I would meet them along with the vessel involved at their boat ramp.  I was informed that the boat fire was extiguished by Fox Lake Fire Department and no one was injured, the operator was able to board another boat driven by a good samaritan.
  
  At approximately 4:32 PM I arrived at Electric Harbor as their tow boat was bringing vessel 1 to shore.  I could see vessel 1 was burned almost to the waterline, and was totaled.  After vessel 1 was brought to shore and put on a trailer, I took several photos (Attached), and could see it was burned beyond repair.  I spoke to (Operator) and asked what happened.  Operator said he was a mechanic for vessel 1 and was driving vessel 1 to troubleshoot a problem.  Operator said he had been out for less than 10 minutes and was cruising at approximately 35 miles per hour when the motor backfired.  Operator slowed down to idle and looked to the stern of vessel 1.  When Operator looked back, he saw flames coming out of the engine cover.  Operator looked for a fire extinguisher, but in his haste, he could not find it.  Operator climbed to the bow of vessel 1 to excape the flames and smoke that was overwhelming him.   A good samaritan pulled their boat close enough for Operator to jump aboard and escape without injury.  Fox Lake Fire Department along with McHenry County Marine unit arrived on scene shortly after and put the fire out.  
  
  I asked Operator about the working order of the boat and if the ventilation system for the engine compartment was turned on, and if vessel 1 was equiped with a spark arresting air cleaner.  Operator said the ventilation system was on, and there indeed was a spark arrestor on the carburetor.  The fire was so hot and vessel 1 was in such disrepair, most items were unrecognizable.  I saw the lower portion of the spark arrestor on the carburetor, that had become detached from the intake manifold.  All the wire casings had been melted, and the valve covers along with some of the upper valve train had been melted, along with mostly all of the engine accesories.  
  
  Per my investigation, the fire was caused by ignition of gasoline vapors that had been collecting in the engine compartment, the backfire was the ignition source.  Due to the intensity of the fire, I am unable to determine if the ventilation system malfunctioned prior to the fire.
  
  The owner as well as the insurance company  has been contacted.  No enforcement was taken against Operator, or any other person(s).
NameOfBodyOfWater: Fox Lake
NearestCityTown: Lake Villa