"Break-in" periods for new or overhauled aircraft engines are highly recommended to increase the efficiency and performance of these machines. It is recommended to run specific types of oils through the engine to rid its walls of any pitting or roughness. When the engine is ran at high power, the piston ring is capable of piercing the oil film and causing minor wear on the newly machined, rough surfaces of the cylinder. This allows the mating metal surfaces to "seat" properly. This process must be closely monitored so as not to cause too much wear. If done correctly, this process can greatly improve performance, safety, and efficiency.
The metal-to-metal contact that occurs is otherwise not desirable and will eventually lead to the collection of floating metal particles within the fluid - as such, it is recommended to drain your oil during this break-in process several times, so as not to cause excess, unwanted wear.
Multi-Viscosity Grade Mineral Oils are typically used for the break-in of aviation engines in which an all-mineral type oil is recommended. The multigrade formulation prevents the unwanted cylinder "glazing" during the break-in process, which could lead to inadequate smoothing and cleaning of the new engine. These oils are formulated to break-in a new or overhauled engine in 25 hours or less. If you need help determining which oil may best suit your aircraft's engine, please call us at 1-855-899-7467.