Abstract: A lifter assembly for an internal combustion engine, including an elongate sleeve having an upper radial wall portion provided with oil feed and oil bleed holes therethrough, through which oil respectively enters and exits the lifter assembly. An elongate, hollow lifter body is reciprocatingly disposed within the sleeve, the lifter body being closed at one end thereof. A plunger is reciprocatingly disposed within the lifter body and has an internal cavity, a low pressure oil reservoir at least partially defined by the plunger internal cavity, the low pressure oil reservoir in at least periodic fluid communication with the oil feed hole, whereby oil from the oil feed hole is received into the low pressure oil reservoir. A high pressure oil reservoir is at least partially defined by the plunger and the lifter body closed end, and is in one-way fluid communication with the low pressure oil reservoir, whereby oil is received into the high pressure reservoir from the low pressure oil reservoir.

Abstract: A lifter assembly for an internal combustion engine, including an elongate sleeve having an upper radial wall portion provided with oil feed and oil bleed holes through which oil respectively enters and exits the lifter assembly. An elongate, hollow lifter body closed at one end is reciprocatingly disposed within the sleeve, and has a plunger reciprocatingly disposed therein. The plunger has an internal cavity at least partially defining a low pressure oil reservoir which is in at least periodic fluid communication with the oil feed hole. A high pressure oil reservoir is at least partially defined by the plunger and the lifter body closed end, and is in one-way fluid communication with the low pressure oil reservoir. A cap is reciprocatingly disposed within the sleeve and engaged with the plunger. Seals are provided which preclude oil from exiting the lifter assembly through the ends of the sleeve.