Operator of Vsl #1 explained that the boat had been winterized by a Marina and the day before did the "breakout", preparing the boat for use. Operator painted the boat, bought new rope and then launched it, started the motor without incident.  When Operator was driving away from the launch he heard an explosion from the motor compartment.  He lifted the lid, flames came out of the compartment and he heard a second explosion from beneath the floor.  Operator got the fire extinguisher and realized that he would not be able to control the fire.  The then exited the boat (with PFD on) and was towed back to the launch by another boater.  
Operator was without injury.  Vessel was total loss.  Portage Township Fire Department put out the fire.  Insurance Company paid for salvaging the boat.
Portage Township              