Systems and methods are described for reducing friction within a transmission and an internal combustion engine including a PCV system. A gaseous fuel source is fluidly coupled to the transmission via a flow control valve and the transmission, in turn, is fluidly coupled to an air inflow line of the PCV system. The flow control valve is configured to control a flow of gaseous fuel into the transmission and there on into the PCV system and crankcase.

The invention provides an internal combustion engine comprising a piston mounted for reciprocating linear motion within a cylinder along a cylinder axis. The piston is coupled to an output shaft by a power transfer assembly arranged to convert linear motion of the piston to rotary motion of the output shaft. The piston has a first head moveable within a first chamber and a second head opposite the first head and moveable within a second chamber. The power transfer assembly has a lubrication system for lubricating moving components of the power transfer assembly. The lubrication system is sealed from the first chamber and the second chamber to prevent the passage of fluid from the lubrication system into the first chamber and the second chamber.

The invention provides an internal combustion engine comprising a piston mounted for reciprocating linear motion within a cylinder along a cylinder axis. The piston is coupled to an output shaft by a power transfer assembly arranged to convert linear motion of the piston to rotary motion of the output shaft. The piston has a first head moveable within a first chamber and a second head opposite the first head and moveable within a second chamber. The power transfer assembly has a lubrication system for lubricating moving components of the power transfer assembly. The lubrication system is sealed from the first chamber and the second chamber to prevent the passage of fluid from the lubrication system into the first chamber and the second chamber.

A breather device includes: a breather chamber into which oil mist in a crank chamber of a combustion engine is introduced; and a breather passage configured to guide oil mist from a crank chamber into the breather chamber. The breather chamber has formed therein a labyrinth structure in which gas-liquid separation of the oil mist is performed. An introduction pipe forming a part of the breather passage is communicated with an upper portion of the crank chamber, and projects upward from an upper end portion of the crank case.

A blow-by heater includes a metal pipe for flowing a blow-by gas therethrough. The metal pipe includes a flat portion on one side along an axis direction and a curved portion on a side opposite to the flat portion and is formed of a metal plate with a joining portion abutting against each other at edges of the metal plate at the curved portion. The blow-by gas heater further includes a resin molded over the metal pipe, and a heating source provided inside resin and directly contacting the flat portion.

An engine includes an air filter assembly having a filter element and a case. A base of the case includes multiple clips, multiple pins, and a catch. The clips are configured to engage a bottom wall of the filter element. A cover of the case includes multiple hinge wings, a hook, and a guide structure. Each of the hinge wings is coupled with a corresponding pin of the base to allow the cover to rotate about the pins. The hook is configured to fasten to the catch of the base for securing the case in a closed configuration. The guide is configured to facilitate placement of the hook and prevent lateral slipping of the hook from the catch of the base. The base and the cover define an interior volume of the air filter assembly sized to receive the filter element.

A blow-by heater includes a tube member allowing a blow-by gas to flow through, and opening in a downstream side, and the tube member is formed such that a thickness of the downstream side decreases toward an opening end.

Methods and systems are provided for a turbocharger of an engine. In one example, a method may include balancing a pressure differential between compressor wheels of the turbocharger.

An intake tube has an inner and outer curved surface adjacent a turbocharger. A crankcase hose connects to the inner curved surface at a hose opening. Upstream ends of first and second struts straddle the hose opening and extend between and connect to the inner and outer curved walls. The struts have an oval-shaped cross section with a larger upstream end that forces air between the two struts and between each strut and the adjacent tube wall to create a low pressure at the hose opening to draw gases from the hose into the intake and turbocharger.

An internal combustion engine using a two stroke cycle includes a pair of opposing cylinder units, each of which are located on opposing sides of a crankcase. In each cylinder unit is a cylinder with a piston disposed in the cylinder. Each piston is coupled to a piston rod that is aligned along an axis that passes through the center of each cylinder bore. The piston rods pass through the crankcase wall into the crankcase chamber, and are further coupled to a yoke. Each cylinder unit has an intake channel from the crankcase chamber to a cylinder intake port in the cylinder. As the piston traverses its upstroke in its cylinder, it creates a vacuum under the piston. At the top of its stroke a piston intake port becomes aligned with the cylinder intake port, allow fuel to be drawn into the cylinder under the piston. As a result, a continuous vacuum is experienced in the crankcase without the need for mechanical valving arrangements.