A young man was injured in the blaze and transferred to Fiona Stanley Hospital from Joondalup Health Campus on Friday morning.
It is understood the victim organised his own transport from Joondalup to Murdoch, with his injuries not believed to be serious.
It took four fire crews just under an hour-and-a-half to extinguish the blaze, which was reportedly ignited by a cigarette reacting with petrol fumes about 12.30am.
The vessel was estimated to be worth about $70,000.
A Fiona Stanley Hospital spokeswoman said on Friday the victim was in a stable condition.