This outboard machine has: a V-type engine (engine) in which a plurality of cylinders are arranged in a V-shape when viewed in a plan view; and a cover that covers the engine. The engine has a plurality of intake ports that form pairs in a V-shape inside the plurality of cylinders in a plan view and a concave space is formed between the plurality of intake ports. The cover has therein an intake path that guides air to the intake port, and is also provided with, at a position that is adjacent to the intake path and enters the concave space, a silencer that attenuates the sound during intake.

This outboard machine has: a V-type engine (engine) in which a plurality of cylinders are arranged in a V-shape when viewed in a plan view; and a cover that covers the engine. The engine has a plurality of intake ports that form pairs in a V-shape inside the plurality of cylinders in a plan view and a concave space is formed between the plurality of intake ports. The cover has therein an intake path that guides air to the intake port, and is also provided with, at a position that is adjacent to the intake path and enters the concave space, a silencer that attenuates the sound during intake.

An internal combustion engine that includes a first fuel pump that sucks fuel through a fuel filter, and a second fuel pump that supplies the fuel to a fuel injection device. The internal combustion engine comprises: a first fuel pipe that interconnects the fuel filter, the first fuel pump, and the second fuel pump set to have a pressure higher than a pressure of the first fuel pump; and a second fuel pipe that connects the second fuel pump to the fuel injection device that injects fuel into a combustion chamber formed in a cylinder portion of the internal combustion engine, a shielding wall covering an outside of the cylinder portion is provided between at least a part of the second fuel pipe and the cylinder portion, and the shielding wall includes a holding portion that holds at least the first fuel pipe and the second fuel pipe.

An internal combustion engine that includes a first fuel pump that sucks fuel through a fuel filter, and a second fuel pump that supplies the fuel to a fuel injection device. The internal combustion engine comprises: a first fuel pipe that interconnects the fuel filter, the first fuel pump, and the second fuel pump set to have a pressure higher than a pressure of the first fuel pump; and a second fuel pipe that connects the second fuel pump to the fuel injection device that injects fuel into a combustion chamber formed in a cylinder portion of the internal combustion engine, a shielding wall covering an outside of the cylinder portion is provided between at least a part of the second fuel pipe and the cylinder portion, and the shielding wall includes a holding portion that holds at least the first fuel pipe and the second fuel pipe.

An outboard includes a plurality of first branched pipes connected to a plurality of first exhaust ports and a plurality of second branched pipes connected to a plurality of second exhaust ports, respectively, wherein the plurality of first branched pipes are connected to a first collecting pipe and the plurality of second branched pipes are connected to a second collecting pipe. A connector connects the first collecting pipe and the second collecting pipe. The plurality of first branched pipes extend in a direction away from the connector in a plan view, and each includes a first exhaust pathway located farther away from the connector than the first collecting pipe is in the plan view. The plurality of second branched pipes extend in a direction away from the connector in a plan view, and each includes a second exhaust pathway located farther away from the connector than the second collecting pipe.

An outboard includes a plurality of first branched pipes connected to a plurality of first exhaust ports and a plurality of second branched pipes connected to a plurality of second exhaust ports, respectively, wherein the plurality of first branched pipes are connected to a first collecting pipe and the plurality of second branched pipes are connected to a second collecting pipe. A connector connects the first collecting pipe and the second collecting pipe. The plurality of first branched pipes extend in a direction away from the connector in a plan view, and each includes a first exhaust pathway located farther away from the connector than the first collecting pipe is in the plan view. The plurality of second branched pipes extend in a direction away from the connector in a plan view, and each includes a second exhaust pathway located farther away from the connector than the second collecting pipe.

The invention provides an internal combustion engine system (1) comprising—at least one combustor (3), and—a first expander (4) arranged to receive exhaust gases from at least one of the at least one combustor (3), and to expand and extract energy from the exhaust gases —characterized in that the system comprises a second expander (5) arranged to receive exhaust gases from the first expander (4), and to expand and extract energy from the exhaust gases.

Methods and systems are provided for balancing a plurality of fuel injectors via a diagnostic. In one example, a method may include adjusting a fuel injection pattern to increase an occurrence of a fuel injection being preceded by a same-cylinder bank fuel injection. The method may further include skipping fuel injections resulting in the fuel injection being preceded by an opposite-cylinder bank fuel injection.

Methods and systems are provided for balancing a plurality of fuel injectors via a diagnostic. In one example, a method may include adjusting a fuel injection pattern to increase an occurrence of a fuel injection being preceded by a same-cylinder bank fuel injection. The method may further include skipping fuel injections resulting in the fuel injection being preceded by an opposite-cylinder bank fuel injection.

An intake structure of the present invention is applied to a multi-cylinder engine including an electrically controlled throttle integrally including a throttle valve configured to adjust an amount of air to be supplied to the engine and an electronic control unit configured to control the throttle valve. The engine intake structure includes: an air cleaner configured to purify the air; and an intake manifold configured to distribute the air purified by the air cleaner to an intake port of each cylinder of the multi-cylinder engine. The electrically controlled throttle is attached to the intake manifold such that the electronic control unit is separated outward in a radial direction of an engine rotation shaft.