Pyke ,that's the area I was talking about, there are 6 head bolts 4 that come from the case up through the jug and head ,but 2 go from the head down through the jug (short studs )in the center front and back ,that's where your leak may be coming from .Ohiomoto ,could be correct the head plug could be leaking and running across the fins then flying off .You need to clean the motor off,and refire it to find out where the leak starts.(blown head gaskets aren't the norm on these low compression motors)