A switchable valve train assembly including a carrier housing defining a hydraulic circuit, a supply assembly, a plurality of rocker shafts, a plurality of separators, and a plurality of rocker arm assemblies is provided. Each one of the plurality of separators divides the rocker shafts into (1) a first chamber extending between a first chamber axial end and the separator, and (2) a second chamber extending between a second chamber axial end and the separator. The plurality of separators each include an orifice defined between the first chamber and the second chamber that provides fluid connection between the first chamber and the second chamber. Locking assemblies of the rocker arm assemblies are selectively actuated based on the supply assembly. The separators ensure that hydraulic fluid within the hydraulic fluid is de-aerated and that the second chambers remain primed with hydraulic fluid for faster actuation of the locking assemblies.

A valvetrain conversion kit for an engine can comprises at least one timing idler rim gear configured to be meshed with at least one of a crank gear of the engine and a cam gear of the engine. The kit can include a first timing gear chamber member having a plurality of engine mounting locations corresponding to a plurality of corresponding cover mounting locations on an internal combustion engine body. The first timing gear chamber member can be configured to be rigidly attached to an engine body at the plurality of engine mounting locations. The first timing gear chamber member can also include a timing idler rim gear shaft supported by the interior surface, the timing idler rim gear shaft having an exterior shaft surface where the exterior shaft surface is configured for rotatably supporting the timing idler rim gear.

An engine is provided with a timing chain cover that covers a side where a timing chain is arranged in a spaced apart manner from the side of the engine. An oil jet extending in an output shaft direction is a hollow member including therein an oil passage. One end portion of the oil jet in the output shaft direction is supported in a hole formed in the engine, and the other end portion of the oil jet extends toward the timing chain cover but does not come into contact with the timing chain cover. A pressing part arranged in a spaced apart manner from the timing chain cover in the output shaft direction is located between the other end portion and the timing chain cover in the output shaft direction, and the pressing part is in contact with the other end portion.

A camshaft cover, a camshaft assembly, and a double-cylinder engine are provided. The camshaft cover has an integral structure, and includes a first shaft cover portion, a second shaft cover portion, a first connecting portion and a second connecting portion. The first connecting portion and the second connecting portion are connected between the first shaft cover portion and the second shaft cover portion, and spaced apart axially.

Provided is an internal combustion engine having an oil circulating structure wherein oil used to lubricate valve operating members in the cylinder head drops onto an oil pan, and the oil accumulated therein is drawn up to the cylinder head again. Each on corners of the squire bottom face inside the cylinder head of the internal combustion engine, an oil dropping hole is provided to allow the oil used to lubricate valve operating members to flow thereinto. Also provided is an oil channel communicating with one or more of the oil dropping hole at the bottom thereof to guide the oil toward the driving gear transmitting the driving force of the engine.

There is provided a lubricating structure for a power transmission mechanism in which a crankshaft is coupled to a piston disposed in a cylinder bore and in which power is transmitted from the crankshaft to a camshaft. The lubricating structure includes: an idler gear that is configured to transmit power from the crankshaft to the camshaft; and an idler gear shaft that supports the idler gear via a bearing. One end portion of the idler gear shaft protrudes into the cylinder bore, and an oil passage configured to guide oil from the cylinder bore to the bearing is formed in the idler gear shaft.

Systems and methods for an engine are provided. The engine includes a straight rocker shaft passing through each of a first rocker arm and a second rocker arm, the first rocker arm being shaped differently from the second rocker arm.

Systems and methods for intermittent supply of lubricating oil to a tip of a rocker arm assembly. In one embodiment, a lubricating oil may be selectively to a tip of a rocker arm via oil channels aligned only during opening of a valve coupled to the tip.

Provided is an internal combustion engine having an oil circulating structure wherein oil used to lubricate valve operating members in the cylinder head drops onto an oil pan, and the oil accumulated therein is drawn up to the cylinder head again. Each on corners of the squire bottom face inside the cylinder head of the internal combustion engine, an oil dropping hole is provided to allow the oil used to lubricate valve operating members to flow thereinto. Also provided is an oil channel communicating with one or more of the oil dropping hole at the bottom thereof to guide the oil toward the driving gear transmitting the driving force of the engine.

An electrically-actuated camshaft phaser used in an internal combustion engine including a camshaft sprocket, configured to receive rotational input from a crankshaft, that includes a sprocket ring gear having a plurality of radially-inwardly facing gear teeth and a radially extending sprocket side; a camshaft plate that includes a camshaft ring gear having a plurality of radially-inwardly facing gear teeth and a radially extending camshaft side; a plurality of planetary gears having radially-outwardly facing gear teeth, each gear with a first radial gear face and a second radial gear face, wherein the planetary gears engage the sprocket ring gear, the camshaft ring gear, or both the sprocket ring gear and the camshaft ring gear; and one or more fluid escapement channels formed in at least one of the camshaft sprocket, the camshaft plate, the first radial gear face, or the second radial gear face.