Is this the same Marvel Mystery Oil that you Northern hemisphere cousins use in your mix for model & hit miss engines?
If it is the same, what's the benefit over a good outboard oil?
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Certainly, the packaging looks like the same stuff. I think it is a fair amount lighter and more easily mixed in with various fuels, but I also think that I have heard that some have used it as two-cycle oil as well.
So, the real answer that I have for your question is ......... I don't know!