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The Real McCoy

Posted by Tom Herren on April 07, 2001

As a retiree from UNOCAL Science and Technology in Brea California, I worked in the Products Research Section, in paricular Technical Services. My understanding of the origin of "the Real McCoy", without documentation, is that it was an ex-slave named McCoy that had developed an oil for lubricating steam engines before the intoduction of automatic lubericators. The engineer had to stop every once in awhile and manually lubricated the pistons and associated machinery with lubricating oil. McCoy's apparently contained animal fat or lanolin to help the oil stick to the wet working parts. As you know, water and oil do not mix very well. Of course the engineer wanted to make shure he had the "real McCoy" oil that worked better that just plain oil. Steam Cylinder oils are still in use today.