Sailboat line clutches are one-way devices that when closed allow the line to be pulled in, but when tension is reversed they seize the line in tension. This allows sails to be set, then the winch can be used on other lines. As line clutches age the cam and base plate develop a smooth wear pattern, and the internal spring loses tension. Then when lines are replaced, especially if the new diameter is smaller, the new more slippery line is not secure in the clutch.

This is a real world example of a repair of a Spinlock XTS clutch manufactured before 2003. Even so, Spinlock came through with upgraded ceramic cams and base plates specifically designed for use with slippery high modulus lines, in this case Warpspeed II.

I am so impressed that Spinlock built on their winning design, not requiring any change in hole placement and continuing to offer replacement parts for over two decades beyond the sale date. I only wish auto manufacturers would follow the same ethical guidelines.

Information provided here is offered for free, but with no guarantee as to accuracy or safety. DIY repair in any form requires acceptance of risk, both from the perspective of the boat and personal injury. Do not proceed with any DIY repair unless you are comfortable accepting those risks. Any misadventure you encounter when attempting to repair your boat is on you.