Ran through some salt water ( tide came in and cut me off from home) and the chain side adjusted must have rusted solid. Don't ask me why the other side didn't, i don't know. It sheared off almost flush so I had to grind it smooth and drill it out as best I could. Ended up with a 1/4-20 bolt replacing the original, looks odd but has served for thousands of miles. Learned to love anti-seize treatment.