The chine should have an insert of hardwood, from about 6 ft
from the stem to the transom.
I would suggest you first consider a temp repair till the end
of season, but if you have time and the leak is serious then maybe do the
thing properly first off.
As a temp repair, scrape out the crack to a depth of half an
inch with a bradawl or similar sharp tool. If the wood is wet, as I suspect
it will be, wash it out with fresh water to remove salt, then allow to dry
for a day or two. Hopefully the timber will be sound. To dry the crack
further, use metholated spirit and wash it into the crack, the meths will
absorb any water and evaporate it off. Then use an epoxy putty and press it
into the gap. You can get epoxy now that will work under water, that will
cope with any residue of water.
This aught to see the season out, maybe longer!
In severe cases I have cut out the wooden batten and used a
grinder to ensure that all wet, soft wood was removed then thoroughly dried
it over a month or two. A new batten was cut to size coated in epoxy, the
gap painted with runny epoxy and then an epoxy putty made up and forced into
all joints, with batten of Iroko on top, really forcing glue in, no leaks
The difficult thing is often the leak on the inside not being
in line with the hole outside! It can travel all along the chine before
finding a way in.
One last thing, there were a few boats I have heard of that
had a mixture of white lead and grease in the joints. A misguided idea. If
you find this you might have to spend more time getting all this out, as it
will not glue if greasy. Meths helps here too! Don't get high on it
Hope this helps.