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2 stroke or four stroke motor oil

I have three gallons of a motor oil that has a bluish/green cast to it. I suspect it is two cycle engine oil for a Yamaha outboard motor, but wanted to know if there was any easy way to determine if it really is two stroke marine oil…other than just try it and see if it fouls the engine. Thanks in advance for any help

If you don’t know what it is (not in origional container) GET RID OF IT, before it damages one of your machines. Two cycle motor oil is designed to BURN with the fuel; it has very different additives, that may damage a 4 cycle engine. You can burn 4 cycle oil in a 2 cycle engine for a short ime, but not the other way around.

Most 2-stroke MARINE (TC-W) oil is “pre-diluted” so it will mix quickly and easily with gasoline. Therefore, it LOOKS very thin, like ATF, because it has a solvent in it. Why is your oil in unmarked containers?? Using unknown lubricants in expensive machinery is very risky…