amen....

AFO = Air Filter Oil

ARO = After Run Oil

They are two very different things.

Air filter oil can be a very low viscosity oil that turns very sticky/thready once rubbed together.

After run oil is something you put into the engine (about 3 drops through the glow plug hole) after you've run your engine.

If you are about to break in a new engine, I'd recommend a couple drops of ARO oil in your engine, wrap the head up in aluminium foil and heat it up with a hair dryer (or something better...like a heat gun) and then try to start it. Most new engines will come well lubricated from the factory.

Unless you are ABSOLTELY sure about the oil you have, I would go out and buy some ARO. Having said that...sewing machine oil MAY work ok, but ask yourself, do I want to risk it???

There are things to think about, like can the oil handle the RPM's of a nitro engine, can the oil mix well with the oil in nitro, what are the ingredients or composition of the oils...etc???

I'm not an expert on this, hence, I would go out and buy specific ARO made for nitro engines.

Good luck.