All the previous posts are great suggestions for finding leaks
, and here's a last resort. I have a 32 year old Oday 25 which is my 9th and probably last boat, due to advancing age.
When all else fails:
Tape over every seam that will allow air to leave the hull
. All the lazarette seams that open to the interior
seams, and leave out one hatch
board section from the main hatch and replace with a plastic garbage bag taped in place. If you have a pop top seal the joint between the hull
and movable portion. Leave the anchor
locker open. Then insert the outlet side of a vacuum thru the garbage bag which replaced the one hatch board and seal around. Then cover the deck
with soapy water. Something that creates plenty of suds and turn on the vacuum. The hull will fill with pressurized air from the outlet side of the vacuum and the soap will bubble where ever there is a leaking air. Those are your entry points for water. All this will not take as long a you would think. On your boat two people can do this in under two hours.
After 4 years of tracking down leaks
one at a time, we now have a boat with dust in the bilge