Abstract: Quick connect coupling adapters for facilitating simplified rapid oil change in an associated internal combustion engine, including a drain opening adapter having an integral body with a central throughbore and a branch throughbore angularly oriented thereto. The adapter includes appropriate means for attaching an end of the branch throughbore to the drain plug opening and means for sealingly attaching the drain plug to one end of the central throughbore. An oil conveying hose is attached to the other end of the central throughbore. The oil conveying hose includes a quick connect coupling releasably attachable to an external pump device. An additional oil fill adapter is positionable in a suitable engine opening such as the dipstick tube or oil fill opening in the valve cover. The oil fill adapter includes a central oil conveying body having an inlet and an outlet means for attaching the outlet in the engine opening, and a fill hose attached to the inlet.