Take a look at the latest video footage of John and Fionn's epic voyage from Mallaig to Oban

On this, Leg 18 of The Great Motorboat Tour, John and Fionn encounter the worst conditions of the voyage so far.

Watch the story unfold as they battle against Force 5-6 headwinds and accompanying seas in their trusty Sealine S34, Shark Bay.

They eventually arrive in the relatively sheltered Oban Marina but things take a turn for the worse. Watch the video to see what happens or click here to watch all the previous videos.