For a short term fix, I've drained the cooling system, pulled the bolt, cleaned the threads, applied thread sealer, installed the bolt, torqued it down, and re-torqued after one heat cycle. Worked fine until I had time to pull the head and resurfaced it prior to re-installing it. Resurfacing was probably overkill but I wanted to be sure that I hadn't messed something up with my quick fix.
"The probability of life originating from accident is comparable to the probability of the unabridged dictionary resulting from an explosion in a printing shop." Edwin Conklin, biologist