Mast Ball, to Socket
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Mast Ball to socket
The Hobie Cat factory recommends upgrading to the one piece design. $17.00 each. Part #53640001. The current welded ball is known to fail during a tack when the mast rotator line is pulled. This is a direct replace part, same size thread, overall length and diameter ball.
To install, knock off the socket, unscrew the welded ball, assemble the ball and socket in bench vise, put lock washer on threads, apply silicone sealant to threads and tighten with vise grip. Wipe excess sealant around teeth marks from vise grip to prevent a rust stain.
Pictured below is the current and the new design.

