Abstract: Apparatus and method for prelubricating newly built, overhauled or rebuilt, and repaired engines including a relatively compact and lightweight pressurized vessel containing a predetermined volume of a light grade prelubricant which may, preferably, be of a specialized or proprietary formulation. The vessel is pressurized with carbon dioxide which serves as the propellant to force the lubricant through an adjustable metering valve on the vessel, an interconnecting hose and, in turn, into an engine oil port wherein the pressurized prelubricant is distributed through existing engine oil passageways, channels, and galleys.