After some filling on the big holes in the cowl, I noticed that the oil door was cracked. It seems that the tension around the latches cracked the fiberglass (the light colored patch on the right).



So I decided to make an aluminium door and use some oher latches. the picture shows the two doors side-by-side, but I will have to make a third door as the lacthes don't have enough grip and the door might open in flight.