Thanks for your input!

I sanded away the gelcoat careful to avoid damaging the plyester below and hoped that the crack was just in the gelcoat (gelcoat cracks before
the glassfibre) but as I said before, I was wrong.

I sanded away more gelcoat on each side, about 1 inch, until I started to see a more normal laminate with glasfibre in it (it changes colour and you cant see through it anymore). Then I sanded even more to get a good area to get the repair to bond with glasfibre.

I chipped away the polyster patch that was without glasfibre and filled the gap with epoxy mixed with west micro fibres and put xxx-fibres with epoxy on top of that so it also covered the area where there where glasfibre was. I finished with peel ply.

I read the post about epoxy not bonding to good with gelcoat, but on the other hand epoxy bonds better with old polyester than polyester. I will use spray gelcoat on top of that and hope that it attaches good enough and try to polish it in nicely.

This damage was at a high stress area but I couldn't see any damage on the deck forward of the pylon or and cracks on the other side of the pylon. I guess I need to thank the bullet proof design for this!

For this minor repair I choosed to fix it myself instead of messing around with the Hobie dealer and trying to get the warranty to cover it.

/hakan