downunder

I was an engine fitter in our air force so I've been around Jet Oil II for many years. Unfortunately back then I didn't know how good it was in our fuels or I'd have had plenty although I used it as a lubricant in my drip feed Myford lathe . Actually I'd have had no hesitation in using oil that had been drained from an engine when an oil change was due because the oil was checked at regular intervals for any contamination. The acceptable levels of contamination were so small we had to use a special tool to punch holes in the cans to avoid tearing the metal. Civil aviation though may not have quite such high standards unless they use the same spectrometric analysis as we did (called a SOAP analysis).