Quote Originally Posted by angrybear View Post

Compressed air is just that it is atmospheric air compressed, and the atmosphere is 78% Nitrogen & less than 21% Oxygen, so the inert N2 acts as a "damper" to the O2 content.
Doesn't stop internal combustion engines from working does it? They only get their oxygen from the atmosphere. I'd say it's unlikely you'd end up with the right oil and compressed air mix for it to combust, but there must be a small chance that you could, surely? Worth avoiding the wrong oil for that reason I would think.