An engine will flood if there's too much fuel going in because of a stuck choke, a bad spark not igniting the fuel, failed temperature sensors, bad fuel regulator, timing...the list goes on.
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check for spark first by holding a plug lead end 1/4 inch away from an earth crank engine , you should feel and see a blue spark. if ok ,remove plugs.itll dry itseft out in half an hour. refit plugs...
usually floods cause a lot of water damage, because of the excess amount of water. this can be prevented by owning a life jacket, or a rather large canoe.