Neck crack


Junior Member
My friend's acoustic got injured falling down from 4x12'' cabinet. When you hold the neck with one hand and push the headstock down with the other hand you can see on one side the fretboard goes apart from the neck and on the other side you can see a crack going diagonal from the point where nut,fretboard and neck wood meet  to the middle of the neck for about 2''. Don't have a picture - know this would help. Just a broken neck - not in two parts but a serious damage. My idea is to use a syringe to fill the crack and then clamp it untill it dries.
Two questions: is that a good way to repair that crack? What kind of glue would work best?