I'm thinking water getting into r/h bank of the block.  Cracked block, head gasket leak, cracked head.  There is no water in crankcase, water level in radiator tank does not seem to go down.  I haven't torn into it yet. I'll remove spark plugs, put my camera scope in each cylinder on r/h bank.  Could it even be intake manifold?  What are your thoughts that I haven't thought of?   Thanks