Hi Charlie,
In answer to your questions: Yes, keel bolts can be tightened while the boat is in the water or on a cradle. Intuitively, many have suggested that the boat needs to be on a cradle with the keel supported so the keel is not "hanging". However, a calculation of loads and forces indicates that the difference in bolt force between in the water and out is on the order of 5% -- doesn't really matter all that much. The total bolt pretension (summing all bolt forces due to the torque) is on the order of 80,000 to 100,000 lbs (depending on bolt sizes of course). The idea that the 5000 lb. keel is "hanging" is misleading. Purpose of the pretensioning is to close the joint and keep it closed under load (boat heeling). Over torquing, as you note, could cause any number of problems -- pullout of bolts from keel, thread damage, crushing of fiberglass, or overstressing of the bolt (yielding). Fracture, if the bolt is not compromised by corrosion, would be very unlikely -- too much torque required, as well as a large bolt elongation. Depending on the rate of leak, decide whether to wait or do it now. If you have the tools, tighten now. I see no need to ground the boat for this -- you really only gain about 5% reduction in the torque for all that risk. The margin of error in the determination of the torque is much larger than 5%. Jeff Laman 1981 C&C34 "Harmony" Ludington, MI
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