Leaky Hull!!

[Sean]

With out fail ever trip last season by the end the bilge would start turn on for a bit, and @ the ramp a little more water then I'd like would pore out when I removed the plug. :o
Today a pressure washed most of the paint of the hull and I think I found the leak. To be sure it is the only leak/crack I was advised to wait for the hull to be bone dry, and then fill the entire bottom of the hull with water!! In theory the leak/crack will become moist and start dripping. The concept sounds like it would work, but the idea of filling my hull like a bath tub is not so appealing...
Once the crack/leak is located what is the best/easiest way to patch, MarineTex?
Any better ideas before I turn my V into a coy pound!
As always, thanks for your help/advise ;D