Yup. It's a random thing. And yes, I have seen some 360s with wet head bolts, but not a 340 as of yet. So far, every 318 I've seen had wet head bolts.
I would pull them one at a time and seal them with red high temp RTV and put them back and re-torque them one at a time. You'll never have them leak again. However, you'll want to drain the coolant completely and blow dry each hole with compressed air first.
