Abstract: A system for prelubricating an engine wherein lubricating oil is delivered to relatively movable parts of the engine during starting in the form of an atomized mist generated by an atomizing spray nozzle operating under an extremely high pressure in the order of 250 to 10,000 psi, so that not only is the mist extremely fine but the oil particles thereof are projected from the nozzle at a high velocity that causes the mist to penetrate into every interstice between relatively movable parts and over every set of relatively movable surfaces so as to coat all parts of the engine which would be subjected to frictional wear were it not for the presence of the oil particles. Moreover, in such system, and particularly in a system employing parts that experience relative rotation at very high speeds such, for instance, as the journals and bearings of a turbocharger, the instant prelubricating system furnishes lubricating oil, e.g.