Cable Hum
My owner's book says that you should lower the keel all the way down, and then take off an extra turn on the winch to allow the cable to go slack. It does sometimes work for me. On the lake where I usually sail there are numerous shallow areas, so I rarely have the keel all the way down. I've grown used to the humming sound. Its a matter of experimentation really. Thumping and banging noise can usually be cured by using the lock-down bolt. But this is a matter of some debate as well. I usually snug the bolt up, to quiet the banging, but never over tighen it. I've known of one that was bent when the keel struck an object under the water. Which, of course, means that the keel could be retracted until the bolt is removed. Why does the keel hum?Because it doesn't know the words.Have fun.