Well, the cause and effect are now much clearer. About 12 years ago I had a tower on the boat and I forgot to put it down on the way home. I went under one of those single lane tunnels and tore the tope half of the tower off. The cracks developed directly in the middle of the attachment of the tower to the upper hull. I think that the boat flexed with that hit. At the time I thought I had been lucky that the hull attachment had held up, there was no damage where it attached. About 5 years later I notice the lower hull had cracked along the port lower rake, it looked like I had hit something. I took it to a boat repair shop and they told me the problem was the boat had rotten stringers and told me they recommended injecting a rigid foam and to fix the crack. I did not research this solution or I would have known the boat is all fiberglass. No way to rot.
Now, about 7 years later I have a crack on the starboard rake and on closer inspection the crack on the port side has also recurred. I went to the Malibu factory and talked to their repair man. Discussed if they had had any other boats come in with a similar problem before I fessed up with what had probably caused the issue. His recommendation was to open up the top, pull the foam out and epoxy from above the below. !!##### What a pain. After 2 days, multiple cut knuckles and my back may never be the same, I have put two layers in of epoxy/s2 glass. I will follow that up with a couple more layers on the inside after a day to cure. Then I work on the outside.
