The oil does a couple things: Lubes where the chain touches the bar. Lubes the rivets, when the chain curves around the sprocket, and around the tip.

The bar oil that's made for that is a bit sticky, so it stays on better. I've heard that new motor oil is acceptable if needed. Used crank case oil will wear out the bar and chain, it's full of abrasive metal pieces.

Eco friendly is good. Be sure to use an oil that has come out of the ground, as it's going back into the ground.
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Christopher A. Young
Learn more about Jesus
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"Ralph Mowery" wrote in message ...

Most any kind of oil can be used. As it goes into the enviroment, you
really should use some that is biodegradable ( or what ever the buzz word
is ). It should not harm the enviroment.