Ricardo, you can find the voids by turning the hull over at night and waiting for the morning dew (get up early and mark them!). (A Sam Devlin trick.) The voids will show up as either wet or dry oval spots (I do not recall which) on the hull. It will prolong the life of your boat if you drill into them and use a syringe to inject epoxy into them. The hole only needs to be big enough for the syringe to reach in. Otherwise, osmosis will pull water into the unfilled voids, even through epoxy and cloth and they will be a source of rot from the inside.
I think you can also tap-tap-tap for the hollow sounding places.
[ 09-17-2002, 05:00 PM: Message edited by: meerkat ]
If you don't think for yourself, someone else will do it for you!