How long is too long for oil change intervals? Ed Kollin, the creator of the oil additive CamGuard and an early researcher for the Exxon Elite oil blend, believes too many operators are stretching oil changes beyond the capabilities of even the best aviation oil. If you only fly between 25 and 100 hours per year, you could be in that camp. As a result, ASL CamGuard has been flight testing a new oil that might safely double oil change intervals. First, some background.
I dusted off several aircraft operating manuals on the bookshelf and found that some manufacturers suggest changing dispersant engine oil at 100 hours. Forget that—those manuals were written in the Reagan era. Aircraft engine manufacturers have since standardized the oil change interval to 50 hours on engines with spin-on oil filters and 25 hours on engines with filter screens. According to Kollin, he has done enough engine wear analysis to suggest there is zero scientific basis in these recommendations, with plenty of trashed cams, rings, spawled lifters and other toasted engine components as evidence. Where’s the smoking gun? There are several.