Marine engines often do not provide access to the crankcase drain plug. A conduit is screwed into the crankcase oil filter port to replace the standard oil filter to execute an oil change. The conduit is shaped like an oil filter and has a large orifice exit port on the bottom which receives a garden hose. The engine is cold cranked to push the oil out the crankcase oil filter port. Then the conduit is replaced with a new oil filter. An alternate embodiment incorporates the orifice and valve into the bottom of a standard oil filter.