Keel rebed notes
http://www.ericsonyachts.org/infoexchange/showthread.php?t=295&referrerid=28
And, here is another thread. There is much keel-related discussion on this site. Once you put the word Keel or Keel Bolt in to the "search" function, you need to further sort out the replies... and spend a bit of time reading.
On any boat with an external metal keel I would reccommend that it be dropped and rebedded every 15 or 20 years. It is ultimately the only way to be sure that corrosion is not affecting the strength of those large SS threaded rods we call "keel bolts."
Another way of looking at this is that any boat built before 1987 is due... now.
Budget wise, I would put this work partly in to the "insurance" part of my boat expenses, like replacing the standing rigging on a scheduled basis.
(Or, like changing the oil in by car every 3500 miles, even if the engine has not shown signs of seizing up yet!)
After our keel was removed at the yard and the mating surfaces were cleaned off (!) it was torqued on again with 5200 sealant. The previous seepage around one of the bolts ceased and the bilge remains dusty dry.
As Steve (or was it Sean?) once noted, boat ownership is not an inexpensive pastime, but the rewards are truly sublime. (I do not remember exact quotes, and must ask their forbearance.)
Loren
ps: when we are out on the water under sail, headed for nowhere in particular, it all seems worthwhile...