INTERNAL COMBUSTION ENGINE FOR SMALL PLANING BOAT

摘要

To provide an internal combustion engine for a small planing boat that makes it possible to prevent supercooling of the internal combustion engine before warm-up while enabling efficient cooling of the internal combustion engine after warm-up. An internal combustion engine for a small planing boat includes: a first cooling water path B through which cooling water introduced from a jet propulsion pump flows toward an internal combustion engine main body via an exhaust manifold; a second cooling water path C through which cooling water introduced from the jet propulsion pump flows toward an exhaust pipe via an oil cooler; and a bypass cooling water path D for branching a part of cooling water in the second cooling water path C which flows out from the oil cooler, so as to merge into cooling water in the first Cooling water path B which flows into the internal combustion engine main body.