So I decided, that a strip of emery paper pulled back and forth around the camshaft would have to do.
This is the before picture:
|Ready to go|
|Strange glow or what?|
Clearly visible is the word 'STEAM' stamped on the end of the camshaft. This differentiates it from the exhaust camshaft on the other side of the engine. It also looks as if there may be a manufacturing date of some time in April 1946. I had previously not been aware that the camshafts had ever been replaced.