Put a good bar oil on your fingers, put the thumb and pointer finger together and pull them apart slowly. A good bar oil will be stringy and tacky. Hydro oil will not do this. That tackiness is what keeps it on longer to do a good job. Posted via Mobile Device
My grandfather used to use my used motor oil on his chain saws. He did use to have cheap crappy electric chainsaws so he didnt really care. Plus they didnt have built in oilers, he just poured some on the bar between cuts. He would run it through a fine strainer to get any metal out (but I change by oil and filters often do there was really metal in it). But I bought him a nice makita electric chainsaw and he uses regular fresh bar oil in that. If you are wondering why he uses electric, he processes all of his wood inside so he uses an electric saw and splitter.
I dont think it is something I would recommend doing. Espeically in saws with a built in oil pump. I have a feeling it would be to thin and could clog the lines easily if there is anything in it.
YOU WANT TO DO WHAT? No. Dear god no. That's a terrible idea, and is sacrelidge from this longtime tree cutter. Hydralic oil could have stuff in it that could really screw up you oiler, bar & chain. And, it's not tacky as bar oil should be, so you'll run out of it quickly.