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1982 civic 1500 Head gasket fails after about 4,000 miles. Head was milled, pressure tested. Always fails in same spot betwee 3 and 4 cylinders in exact same spot . I have been meticulous about cleaning bolt threads, torqueing pattern, purging air from cooling system, etc. Torque to 43 lbs. I tried retorqing one time after in ran awhile and cooled, but all bolts were still at 43 lbs.
I put a straight edge on the block and it seems to be straight. How likely is it that it could be the block, if it is much harder and tougher metal than the head? I'm getting tired of replacing the head gasket with every oil change!