Keel bolt problem...

[Guest]

The keel bolts in my C-22 are showing signs of corrosion. I had an inspection done and was told they will be okay for about the next two years if the bilge is kept dry. The man suggested a light coat of epoxy to help keep the water out. Has anyone done this? Any other preventative suggestions?Thanks.

 

[Ralph Johnstone]

Hard to believe .......................

....... that the bolts are not stainlness, but that being the case that they are lowly carbon steel, there is little that can be done. The corrosion that you can SEE is not the problem, it's the corrosion that you CAN'T see that may cause a problem in the future. The corrosion under and beneath the nuts on the bolts is where to expect problems. As the important corrosion points are hidden, I don't think there is much that can be done to reduce the rate of corrosion. If you are in salt water, coating them with epoxy may actually increase the problem due to concentration cells and other gremlins. However, if you are in fresh water, heating them to dry them and then coating them may help providing there is no leakage coming from the keel to hull seal.Best of luck,s/v Island Hunter

 

[Dave]

Keel Bolt Problems

The problem I'd worry about is what is called stress corrosion. At the root of the thread is a highly stressed notch in the presence of salt water. The high stress keeps the atoms in a high energy state making them more reactive and the salt water sitting in a crevice will become acidic and start to dissolve the metal. I would remove the nuts and washers, Chase the threads with a die, use a scotch brite pad to clean up the threads further. Dry everything out thoroughly!!! Then coat the whole mess with copious quantities of waterproof grease and torque the nuts down. Neverseize is another option to protect the threads. If they look really bad and you cant clean them up then you have a bigger repair job!!Best of luckDave