Coolant weep around head nut

[Synchro909]

The head stud holes are blind until some ham fisted person screws a stud in too tight and breaks it out. I've even found a chunk of CI in the water jacket from this. This leak is caused by such a break. When I find a hole that goes right through into the water jacket, I seal that stud thread when I put it in to avoid this happening.
I woke up to what was happening when I had exactly this same thing happen. Some radiator sealer fixed it for years till I rebuilt the engine, then I sealed the thread with some Permatex #2.