You need a 2 items to find the leak.
1)high volume low presuere pump like the ones you fill air beds or floatable kid toys with.
2)a Spray bottle with a mixture of dish soap and water.
put a few pumps of air in the drain plug of the leaky hull and start spraying it with the soap/water mixture. You will soon find the leak. REMEMBER. YOU DO NOT NEED MUCH PRESSURE AT ALL!!!!!
I found several area where the deck lip had separated. Probably from 1) tie downs or 2) being rolled over on its side for one reason or the other.