Leak

If you have inspection hatches, they like to leak. Reconditioning the seals may help.

What year and type of boat. How much water are we talking about? Could it be condensation?

New Tiger (3 months). Two cup of water for a day of sailing. What really puzzle me is that the hull is airtight. It also happen only on the port hull, I had a bad collision and a repair done one month ago.

Perhaps your leaking area is functioning like a valve - will hold the pressure inside but not a vacuum. A hull can create a vacuum when it's hot on land and then is put in cool water.

Jake,

Good point! I made a hull test kit awhile ago that works great. I use an inspection port cover that has a tube in it that I attach to a shop vac. attached to the tube is a nipple (air hose attachment) that I connect a low pressure vac gauge to.

I seal the hull (put in the plugs, bolts and test cover use the shop vac to draw out the air (takes a few seconds ---- be careful not to draw too much) I take it down to about 8 lbs neg. pressure. then wait for a leak.

NOTE: The tube has a one way plunger valve on it to keep the seal(vac).

Finding the leak is a process of elimination. Bolts first, then ports, then plugs. Usually the ports leak first. But I have caught a bad seal in a daggar well (not fun to fix either). If you can't draw a vac. check the ports first then the daggar wells everything else is too small to fight the shop vac's power.

I have never had a delam problem so I can't tell you how it would react or if it would at all. Well, come to think of it a delam would probably show by caving in under the pressure. 8lbs is not alot but the sounds of the air rushing in past the valve makes you think twice.

You can also revers the process by capping the valve and inducing air to 5-10 positive airpressure and soap testing the hull after the fix.

Good hunting

Steve