Checking and Replacing: Keelbolts, Part 1
It is almost impossible to generalize about the longevity of keelbolts, since so many variables influence the life of a metal immersed in water.
The largest fasteners in any sailboat with outside ballast are likely to be the bolts holding the ballast keel to the hull. As a rule, designers specify keelbolts by a tremendous factor, on the order of ten to one or more. Nevertheless, this safety margin does not guarantee eternal life for keelbolts. Corrosion takes its toll, sometimes more quickly than you might think.