Inspecting the keel bolts isn't a terribly difficult process, but to do right does take some heavy
equipment. Basically you put the
boat on stands, take off the
mast, then unbolt the keel and move the
hull to a seperate set of stands while leaving the keel in place.
So it's just one more pick than a
mast off bottom job. One of the upsides to steel bolts is as soon as you
lift the
hull away from the keel you will know if they are bad. So long as they pass a visual
inspection then you can just drop the hull back on the keel and off you go. With stainless bolts you should have the bolts dye tested (or do it yourself) to check for cracks.
Replacing bad keel bolts has a massive range depending on what you do and the design of the keel.
If you have J bolts into lead then you have to melt the lead away and slide the keel bolts out, replace with new and remelt lead to fill the channels. Frankly I would just send a keel like this to MARS and let them fix it. The
shipping costs aren't so high I would trust a local shop to do as good of a job.
If the keel is held on by threaded rod (generally into cast iron or steel) then you just take the rod out and replace it. This is a pretty simple job anyone can do.