Marine: Boating, Sailing, PWC, GPS and Navigation - Fiberglass repair help needed

I recently purchased an old glass fishing boat, and it is taking on water. I filled the hull with water while on the trailer, and found the leak is coming from previous object impact damage a the bottom of the arc made from the bow to the area where the bottom flattens out. I presume from hitting logs or rocks. Anyway, the leak is apparently about the diameter of a ball point pen. I was thinking I could lay up glass epoxy and glass tape for about 18 inches to fully cover the area leaking. If this will work, how many layers would be recommended. I assume I should first sand the area to insure a good bond. Any step by step hints would be greatly appreciated. I've never done this type of repair before.
Thanks,
John H.

I would grind the dammaged area about half way through and then perform the repair with a fibreglass repair kit, then I would move to the inside repeating the same procedure, gel coat the repair. Also apply a keel shield which will help with protecting against any further dammage.