I had a problem where the striker seemed to be jammed. With much help from Morlock on here I got it sorted.
The cog in the base had become de-soldered from the flint wheel pinion shaft. Difficult to describe without photos, but strip everything down as far as possible, then stick a screwdriver in where the striker goes, and the entire base assembley should lever off. Might take a bit of force, If you are still stuck tomorrow I will take some pics to demonstrate.