Abstract: An engine flushing system that utilizes any fresh water source with a hose, and a quick-connect/disconnect device that when mated with it's mating piece, locks and allows the water to flow through the system. The free flowing valve becomes air tight when locked together with its mating piece thereby allowing the water to circulate through the system, which is connected to the water intake hose of each outboard motor. When the fresh water source fitting is not inserted in the quick-connect valve piece, the suction created by the outboard motors causes the valve to make an air tight seal and to block the flush systems canal thereby allowing water to circumnavigate and flow through the water cooled hoses in the outboard thus allowing multiple outboard motors to be flushed simultaneously in one single operation.