Cracked hull

[fishstu]

I have found a 6 in wide crack on the outside of my SC20MA hull. The crack runs outward from just off the center spar (port side) approx 3 ½ ft forward of transom. Tapping using a hammer, forward of the crack sounded very solid and stiff, abruptly right at the crack and farther back the hull sounded different and not so solid. To me it looks like a “hinge” stress crack caused by an abrupt change in hull stiffness in the wrong place.
My next step is to take off the seat post fitting and look in.
I have a feeling that I am going to have to open up the deck to properly fix this.

Has anybody else seen a similar crack, have ideas of the cause suggestions for the fix?, Also how to open up a good deck to do a similar fix

All advice is extremely appreciated
Fishstu

Many thanks Bryan

http://i56.photobucket.com/albums/g1...ll002Small.jpg

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