Abstract: A rocker assembly including a rocker shaft having an outer surface, main oil passage, a first radial passage and a second radial and a rocker arm having a first end and an inner cylindrical surface defining a bore, wherein the rocker shaft is received in the bore to pivotably mount the rocker arm onto the rocker shaft. The rocker arm includes a hydraulic lash adjuster mounted within the first end and a first oil passage having an inlet at the inner cylindrical surface and an outlet in fluid communication with the hydraulic lash adjuster. The inner cylindrical surface is spaced apart from the outer surface of the rocker shaft by a radial clearance, and wherein an inlet to the first oil passage and a first outlet of the first radial passage are in a loaded region of the radial clearance.

Abstract: A hydraulic lash adjuster includes a longitudinally extending pushrod having a proximal end and a distal end, and a cavity located at the distal end and a piston received in the cavity. The piston includes an internal reservoir and a fluid pathway to the internal reservoir. The fluid pathway includes a longitudinal passage and a radial passage.

Abstract: A rocker arm assembly having a rocker arm with a first end defining a first cavity, a second end opposite the first end, a bore positioned between the first end and the second end for pivotally mounting the rocker arm within an engine, and an oil passage extending from the bore to the cavity. A hydraulic lash adjuster is positioned within the cavity and has an oil inlet in fluid communication with the oil passage. The rocker arm has a vent passage configured to place the oil inlet in fluid communication with an area exterior to the rocker arm.

Abstract: A rocker arm assembly having a rocker arm with a first end defining a first cavity, a second end opposite the first end, a bore positioned between the first end and the second end for pivotally mounting the rocker arm within an engine, and an oil passage extending from the bore to the cavity. A hydraulic lash adjuster is positioned within the cavity and has an oil inlet in fluid communication with the oil passage. The rocker arm has a vent passage configured to place the oil inlet in fluid communication with an area exterior to the rocker arm.

Abstract: A rocker assembly including a rocker shaft having an outer surface, main oil passage, a first radial passage and a second radial and a rocker arm having a first end and an inner cylindrical surface defining a bore, wherein the rocker shaft is received in the bore to pivotably mount the rocker arm onto the rocker shaft. The rocker arm includes a hydraulic lash adjuster mounted within the first end and a first oil passage having an inlet at the inner cylindrical surface and an outlet in fluid communication with the hydraulic lash adjuster. The inner cylindrical surface is spaced apart from the outer surface of the rocker shaft by a radial clearance, and wherein an inlet to the first oil passage and a first outlet of the first radial passage are in a loaded region of the radial clearance.

Abstract: A hydraulic lash adjuster includes a longitudinally extending pushrod having a proximal end and a distal end, and a cavity located at the distal end and a piston received in the cavity. The piston includes an internal reservoir and a fluid pathway to the internal reservoir. The fluid pathway includes a longitudinal passage and a radial passage.

Abstract: A method of retrofitting a rocker arm assembly for an engine includes removing a first rocker arm assembly from the engine such that a camshaft of the engine remains in the engine. The method also includes providing a second rocker arm assembly that includes a rocker shaft, a rocker arm, a pushrod, and a hydraulic lash adjuster. The rocker arm is connected to the rocker shaft such that the rocker arm can pivot relative to the rocker shaft. The rocker arm has a first end, a second end, and a first oil passage. The pushrod has a top end and a bottom end, in which the top end is connected to the second end of the rocker arm and the bottom end is configured for engaging a camshaft of the engine. The hydraulic lash adjuster includes a housing, a first body member, a second body member, a check valve, and a biasing member. The first body member is disposed in the housing such that a first radial clearance exists between an outer surface of the first body member and an inner surface of the housing.

Abstract: A valve actuation system is disclosed for an engine. The system may have at least one gas exchange valve, a rocker shaft, a camshaft, a rocker arm connected to the rocker shaft and operatively engaged with the camshaft, a valve bridge engaged with the at least one gas exchanger valve, a lash adjuster disposed in the valve bridge, and a button configured to slide on the valve bridge. The system may further include a pin fluidly connecting the rocker arm to the button and having an elongated cylindrical shaft with a first open end inside the rocker arm and a second end inside the button. The pin may also have a head connected to and a reservoir formed in the elongated cylindrical shaft. The pin may further have passages extending from the bore of the rocker arm to the reservoir, and s passage extending from the reservoir through the head.

Abstract: A valve actuation system is disclosed for an engine. The system may have at least one gas exchange valve, a rocker shaft, a camshaft, a rocker arm connected to the rocker shaft and operatively engaged with the camshaft, a valve bridge engaged with the at least one gas exchanger valve, a lash adjuster disposed in the valve bridge, and a button configured to slide on the valve bridge. The system may further include a pin fluidly connecting the rocker arm to the button and having an elongated cylindrical shaft with a first open end inside the rocker arm and a second end inside the button. The pin may also have a head connected to and a reservoir formed in the elongated cylindrical shaft. The pin may further have passages extending from the bore of the rocker arm to the reservoir, and s passage extending from the reservoir through the head.