Patent ID: 8479691

Claim:
A method for cooling an engine of a marine propulsion system, the method comprising: pumping water from a body of water in which the marine propulsion system is operating; pumping the water through the engine and then back to the body of water; directing the water through a cooling jacket of an exhaust manifold of the engine, through a head of the engine, and then through a block of the engine; directing the water through the head of the engine via an exhaust port cooling jacket disposed in thermal communication with a plurality of exhaust ports in the head of the engine; and directing the water into an upper portion of the head of the engine and then downwardly in the exhaust port cooling jacket so as to sequentially cool the exhaust ports in the plurality as the water moves downwardly in the exhaust port cooling jacket; directing the water from the exhaust port cooling jacket into an intake port cooling jacket that is separated from the exhaust port cooling jacket by a wall and disposed in thermal communication with a plurality of intake ports in the head of the engine; and directing the water into a lower portion of the head of the engine and then reversely directing the water upwardly in the intake port cooling jacket to thereby sequentially cool the intake ports in the plurality as the water moves upwardly in the intake port cooling jacket.