The 1150 head has two kinds of washers and bolts. cylinders 1&4 have copper washers and acorn style nuts on the cyinder studs. cylinders 2&3 have steel washers and nuts that arn't acorn style. I had an oil leak where the oil was going under the metal washer on cylinder 2 and traveling down the stud. I changed cylinder 2 and 3 over to copper washers and re- tourqed them. The leak has dissapeared so far ( i only have 50 miles since doing it) but my question is this.................... why do they have two kinds of washers and nuts? ( they all have the same tourque value) can I do any harm by changing the metal washers over to copper like the other cylinders? ...........thanks..........................................skip