Hello,
Try loctite 271, this will keep the stud from loosening. it must be clean and dry on both parts, carb cleaner and compressed air to blow out the head hole, use a rag around the nozzle so you don't get blow back,!
I assume your torquing it to some spec called out by ???????.
and the stud is shouldering on the C/B shoulder of the stud at the hex.
You will probably have to do all 16, I did this on my build.
Good luck,
Mark
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