The Expert’s Advice for Engine Break-In Aug 25, 2017 · Proper oil use and levels are critical. Continental Motors recommends mineral oil for engine break-in for all of its engines.Whereas, Lycoming Engines recommends Mineral oil only for it Aug 25, 2017 · Proper oil use and levels are critical. Continental Motors recommends mineral oil for engine break-in for all of its engines.Whereas, Lycoming Engines recommends Mineral oil only for its normally aspirated models.Mineral oil allows for the internal engine parts to wear into each other and seat properly instead of the desired …