A cowling for an outboard motor extends from port side to starboard side in a lateral direction. The cowling includes port and starboard inlets that direct flow of intake air into the cowling and face outwardly in the lateral direction. The cowling further comprises port and starboard duct systems. Each duct system is configured to receive and convey intake air from one of the port and starboard intake ports to an intake conduit for the outboard motor. Each duct system defines a first separation region that receives and conveys the intake air laterally outward to separate a first portion of water from the intake air. Each duct system further defines a second separation region that receives and conveys the intake air from the first separation region laterally inward to separate a second portion of water from the intake air.

An intake manifold which can ensure a pressure resistance strength, a mechanical strength, and the like and also reduce a passage resistance and an outboard motor which can be made smaller and thinner in a width direction. A resinous intake manifold made of a resin and configured to be applied to an engine of an outboard motor includes: a surge tank which forms a flat contour and includes an intake inlet; and a plurality of branch pipes which defines intake passages communicating with an internal space of the surge tank, wherein a contour wall of the surge tank includes a plurality of ridge portions which protrudes toward the internal space and is oriented toward the intake passage side.

An intake plenum is for a marine engine, the marine engine having first and second throttle devices for controlling flow of intake air to the marine engine. The intake plenum has an airbox providing an expansion volume, first and second inlets that convey the intake air in parallel to the expansion volume, first and second outlets that convey the intake air in parallel from the expansion volume to the first and second throttle devices, and first and second Helmholtz-style attenuator devices located at the first and second outlets, respectively. Together the first and second inlets, expansion volume, and first and second Helmholtz-style attenuator devices are configured to attenuate different frequencies of sound emanating from the marine engine via the first and second outlets.

A V-type multi-cylinder engine including a pair of banks, includes: an intake member forming an intake passage through which air is guided from outside; a pair of throttles each configured to regulate an amount of the air sucked into each of the pair of banks through the intake passage; and one single temperature sensor configured to detect a temperature of the air in the intake passage. The intake member includes a pair of openings downstream in a flowing direction of the air. Each the pair of throttles is connected to each of the pair of openings. The temperature sensor is disposed between the pair of openings.

An internal combustion may include a cylinder having a first combustion chamber at one end and a second combustion chamber at an opposing end, first and second cylinder heads located at an end of the first and second combustion chambers, respectively, and a double-faced piston slidably mounted therein. The piston may be configured to move in a first stroke that includes an expansion stroke portion and a non-expansion stroke portion. The engine may further include first and second piston rod portions extending from opposite faces of the piston. A recess in the piston rod portions may be configured to communicate gases between a combustion chamber and locations outside the cylinder. There may also be a chamber surrounding the first or second piston rod portion, the chamber configured to be supplied with gas and the chamber being isolated from the first combustion chamber and the second combustion chamber.

An off-road vehicle includes an air intake system that comprises an opening that, in operation, receives air, and an exhaust system that includes an exhaust stack positioned in the opening of the air intake system.

A breather device for an outboard motor engine, the outboard motor engine including a breather chamber formed in an engine main body, and an intake passage guiding air into the engine main body, in which an intake port of the intake passage is open inside an engine cover that covers the engine main body, the breather device includes a resonator chamber communicating with an upstream side of the intake passage, and a breather passage extending from the breather chamber and communicating with the resonator chamber.

A front structure of a saddle ride type vehicle includes a headlight unit, a front cowl, and a middle cowl. At a position outside the headlight unit in the vehicle width direction, an air intake portion opening to the front side of the vehicle is formed between the front cowl and the middle cowl. The front cowl includes a partition wall configured to divide the air intake portion into an upper region and a lower region. The lower region forms an inlet of an air intake path of an air cleaner. The upper region forms a first wind guide path configured to discharge a traveling wind to the rear side of the front cowl.

A system and method to selectively control intake air temperature of a dual fuel engine are provided. The dual fuel engine intake air temperature is automatically modified based on a determined fuel mode at which the dual fuel engine is operating or instructed to operate.

An outboard motor includes an engine to rotate a propeller and an engine cover that houses the engine. The engine cover includes two divided covers disposed above the engine and that directly face the engine. The two divided covers include two connections that are connected together and that overlap the engine in a plan view.