Urethane foam is a potential problem in marine use as it is not closed cell
and therefore will, over time, absorb liquids. It is popular because of its
resistance to acetone and other like solvents. Unfortunately, there is no
way, other than mechanical removal, to get rid of it. As your boat is small,
I suggest using a sawsall or a large flex disc, remove the entire deck. Turn
it upside down and remove the inner liner and foam to destruction. Repair
the offending water leaks, which caused the problem in the first place. Then
refoam upside down leaving the deck margin clear for rebonding to the hull.
After the foam is sanded straight to the original dimensions, then layup the
new inner hull liner on top. Rebond the deck to hull margin, patch the bond
space at the deck margin with additional foam and reglass the hull liner on
top in the previous manner. The job will take 60 days part-time.
Steve
PS I have done this on a 21' trihedral hull on the entire port side and it
was very successful. It is not as difficult as it sounds. Keep in mind that
the deck shape will distort under gravity upside down when the foam and
inner liner is removed. So it is important that the deck is fully supported
by shims and wedges before this process begins. In that way, its shape will
be retained.


"don" wrote in message
ups.com...
Have a 21', center console, fiberglass sport fisher, made in 1972.
Another post mentioned a chemical way of removing foam, and others
mention cutting out the old foam. Cutting doesn't seem practical, the
entire deck would have to have access holes cut all over. Anyone know
what chemical method is available, if any? Many thanks, don.