Lubrication Description (1)
Engine Mechanical - 5.3L L84 or 6.2L L87 | Description and Operation | Document ID: 5033656 Lubrication Description
Engine lubrication is supplied by a variable displacement single-stage (L82, L84) or two-stage (L87) vane-type oil pump assembly (4). An oil control solenoid valve , controlled by the engine control module (ECM), mounted to the two-stage oil pump provides duel stage functionality. The oil pump is mounted on the front of the engine block and driven directly by the crankshaft sprocket. The pump rotor and vanes rotate and draw oil from the oil pan sump through a pick-up screen and pipe (7). The oil is pressurized as it passes through the pump and is sent through the engine block lower oil gallery. Pressurized oil is directed through the engine block lower oil gallery to the full flow oil filter (6) where harmful contaminants are removed. A bypass valve is incorporated into the oil filter, which permits oil flow in the event the filter becomes restricted. Oil exits the oil filter (6) and is then directed to the external oil cooler located in the radiator and back to the left side of the oil pan. The oil is then directed to the oil pressure sensor (8) and then to the upper main oil galleries and the AFM oil control solenoid valve galleries (5). Oil from the left upper oil gallery is directed to the crankshaft and camshaft bearings. Oil that has entered both the upper main oil galleries also pressurizes the valve lifter assemblies and is then pumped through the pushrods to lubricate the valve rocker arms and valve stems. Oil returning to the pan is directed by the crankshaft oil deflector. An oil passage at camshaft bearing location 2 permits oil flow into the center of the camshaft. Oil enters the camshaft exiting at the front and into the camshaft position (CMP) actuator solenoid valve (2). The CMP valve spool position is controlled by the engine control module (ECM) and CMP magnet (1). When commanded by the ECM, the CMP magnet repositions the CMP actuator solenoid valve spool directing pressurized oil into the CMP actuator (3) to control valve timing. Camshaft Position Actuator and Solenoid Valve Description. With active fuel management activated, the ECM commands, based on driving conditions, some combination of the 8 oil control solenoid valves to open, directing oil through the engine block oil galleries to the intake and exhaust AFM valve lifters.