A cooling system is for a marine engine. The cooling system has a cooling fluid conduit that is configured to convey cooling fluid for cooling at least one component of the marine engine; a strainer disposed in the cooling fluid conduit and configured to strain the cooling fluid; and a quick connector that is manually operable to connect and disconnect the strainer from the cooling fluid conduit.

An outboard motor includes an internal combustion engine. The internal combustion engine includes a cylinder head including a fuel injector including an injection portion, and an ignition including an ignition portion that provides ignition within a combustion chamber. The ignition portion is deviated in an upward-downward direction, in which a valve actuating shaft extends, with respect to the injection portion in a central region of the combustion chamber. The ignition is mounted in the cylinder head.

An outboard motor includes an engine, an engine cover with which the engine is covered, an intake pipe disposed between an outer surface of the engine and an inner surface of the engine cover, and a battery. The engine includes a piston that reciprocates rectilinearly and a crankshaft that rotates around a crankshaft axis extending in an up-down direction. The intake pipe is connected to a first outer surface of the engine along the crankshaft axis, and supplies air to the engine. The battery is disposed between a second outer surface of the engine, which is different than the first outer surface, and the inner surface of the engine cover.

Combustion air intake ports are provided on left and right side faces of an upper part of an engine cover. An outer louver is disposed to confront the combustion air intake port, and an inner louver is disposed inward of the outer louver at a predetermined interval to face the outer louver. The combustion air received from the combustion air intake port passes through the outer louver and the inner louver and is guided to the engine unit from the guide hole. In this case, a splash of water is dispersed in the outer louver, and a large-sized water droplet falls down due to its self-weight before the combustion air reaches the inner louver, so that a small-sized water droplet can be collected and removed using inertial impaction at the inner louver. Therefore, it is possible to effectively separate water.

A fan is suitable for an air-guiding system of an outboard motor including an internal combustion engine and a covering hood bounding an engine interior space. The engine drives the fan, which is connected to an upright shaft journal projecting beyond an upper side of a housing of the engine. The covering hood has air flow openings, and the fan influences the air flows in the covering hood interior space. A flywheel, fixedly attached to the upright shaft journal, carries a fan wheel of the fan. The fan wheel is set in place from above, and the flywheel carries the fan wheel for conjoint rotation. Airflows enter the interior space via an inlet opening and a first conducting device, and the airflows, under the action of the fan, act upon at least parts of surfaces of the internal combustion engine and the auxiliary units to cool the internal combustion engine.

An outboard motor engine has a cylinder block including vertically stacked cylinders divided into two cylinder banks arranged in a V-shape. Two cylinder heads define intake passages, each intake passage corresponding to a respective cylinder. Air intake manifolds include air intake runners that extend from an opposite end of the engine, around outer sides of the cylinder block, and respectively connect to the intake passages. Two vertically extending fuel rails are respectively located between the first cylinder head and the first air intake manifold and between the second cylinder head and the second air intake manifold. The fuel rails are integral with either the respective cylinder heads, or the respective air intake manifolds. Fuel injectors are coupled to the fuel rails and vertically spaced from one another with respect to each fuel rail such that each fuel injector is associated with a respective cylinder.

A draining arrangement of a propulsion unit of a marine vessel. The propulsion unit includes a shell structure. The shell structure limiting at least one bottom section configured to receive liquids. The draining arrangement including a pneumatically operated drainage arrangement including an intermediate tank within the shell structure, a pressurizing arrangement functionally connected to the intermediate tank and configured to selectively provide a vacuum in the intermediate tank or an excess pressure in the intermediate tank, a first liquid line that is provided between the intermediate tank and said at least one bottom section, and a second liquid to line that is provided between the intermediate tank and a collector arrangement within the hull of the marine vessel.

A display device for an outboard motor includes a storage device storing unique information of the outboard motor. The display device for the outboard motor has a gauge mode and a service tool mode as display modes. By mounting the display device for the outboard motor to a specific boat, both an operating state of the outboard motor and the unique information of the outboard motor are displayable in the gauge mode. Only the unique information of the outboard motor is displayable in the service tool mode. The display modes are configured to be switched between the gauge mode and the service tool mode.

An outboard motor including an internal combustion engine for propelling a ship is equipped with an air-guiding system using a covering hood surrounding surfaces of the internal combustion engine and auxiliary units. The covering hood is provided with airflow inlet and outlet openings in its interior, and a fan driven by the internal combustion engine influences airflows in the covering hood. An air-guiding system includes channeling devices for partial air flows. First partial air flows are fed as intake air to an engine intake system, and second partial air flows act, with the aid of the fan, on surfaces of the internal combustion engine and the auxiliary units heated by operation of the internal combustion engine. The heated airflows are conveyed by the fan and a third channeling device as exhaust air via an outlet opening in the covering hood outside of the covering hood or into the atmosphere.

A breather apparatus for an engine includes a breather chamber, one side portion and other side portion of the breather chamber, and a bottom face of the other side portion. The breather chamber is formed, along substantially half a circumference of a cylinder bore, in a cylinder block. The one side portion of the breather chamber is provided with a blow-by gas introduction hole leading blow-by gas in the crank chamber to the breather chamber and a one-way valve opening and closing the blow-by gas introduction hole. The other side portion of the breather chamber has a pipe connection hole connecting a breather pipe to the breather chamber and with a breather oil return passage. The bottom face of the other side portion projects into the crank chamber to a level lower than a bottom face of the one side portion.