BODY AS 2477792 - Caterpillar

oil from the oil pan flows through a strainer and a pipe to the suction side of the engine oil pump. Pressure for the lubrication system is supplied by the oil pump. The crankshaft gear drives a lower idler gear. The lower idler gear drives the oil pump gear. The pump has an inner rotor and an outer rotor. The axis of rotation of the rotors are off-center relative to each other. There is an interference fit between the inner rotor and the drive shaft.The inner rotor has four lobes which mesh with the five lobes of the outer rotor. When the pump rotates, the distance increases between the lobes of the outer rotor and the lobes of the inner rotor in order to create suction. When the distance decreases between the lobes, pressure is created.The lubricating oil flows from the outlet side of the oil pump through a passage to a plate type oil cooler. The oil cooler is located on the right side of the cylinder block.The lubricating oil flows from the oil cooler through a passage to the oil filter head. The oil then flows through a bypass valve that permits the lubrication system to function if the oil filter becomes blocked. Under normal conditions, the oil then flows to the oil filter.The oil flows from the oil filter through a passage that is drilled across the cylinder block to the oil gallery. The oil gallery is drilled through the total length of the left side of the cylinder block.Lubricating oil from the oil gallery flows through high-pressure passages to the main bearings of the crankshaft. Then, the oil flows through the passages in the crankshaft to the connecting rod bearing journals. The pistons and the cylinder bores are lubricated by the splash of oil and the oil mist.Lubricating oil from the main bearings flows through passages in the cylinder block to the journals of the camshaft. Then, the oil flows from the front journal of the camshaft at a reduced pressure to the cylinder head. The oil then flows through the center of the rocker shaft to the rocker arm levers. Oil flows to the hydraulic lash adjusters in the rocker arm levers. The valve stems, the valve springs and the valve lifters are lubricated by the splash and the oil mist.The hub of the idler gear is lubricated by oil from the oil gallery. The timing gears are lubricated by the splash from the oil.Engines have piston cooling jets that are supplied with oil from the oil gallery. The piston cooling jets spray lubricating oil on the underside of the pistons in order to cool the pistons.