It is designed so the pin, a bolt, goes through the centerboard housing from one side to the other with metal washers and then rubber washers (about 2 ½ inches in diameter) on each side of the housing. Those rubber washers tend to allow some water through.
A former Mariner owner suggested a design like this:

A= Centerboard Trunk
B= Swing Keel
C= Centerboard Pin
D= Threaded Pipe Nipple fiber glassed to side of the Centerboard Trunk
E= Cap screwed onto threaded end of Pipe
Does anyone have any comments or suggestions?
Does anyone know of any softer material for washers that may provide a better seal?
Thanks,
Sorry for the freehand drawing. One of these days I will find a free CAD drawing program and learn how to use it.
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