F4A Won't Start

[Jonboy F]

I have a 2004 F4A as a back up to my main F30. I went to start it yesterday and pulled the start cord and it jams - or so I thought. I took the casing off and realise that the black flywheel (which the cord should grip and spin) just seems to be locked in position and won't turn....any ideas?

[boats.net]

Pull spark plug to see if cylinder is full of oil.