NUT-HEX 4820069 - Caterpillar

Illustration 1 g01950413
Lubrication system schematic
(1) Passage to the rocker arms
(2) Cylinder head gallery
(3) Passage to pushrod lifters
(4) Piston cooling jets
(5) Oil supply line for the fuel pump
(6) Oil supply line for the air compressor
(7) Main bearings
(8) Camshaft bearings
(9) Main oil gallery
(10) Turbocharger oil supply line
(11) Supply for the number 4 main bearing
(12) Passage to camshaft idler gear bearing
(13) Oil filter bypass valve
(14) Passage
(15) Oil cooler bypass valve
(16) Engine oil filter
(17) Engine oil cooler
(18) Auxiliary engine oil filter (if equipped)
(19) Engine oil pump
(20) Oil pump bypass valve
(21) Engine oil pan Engine oil pump (19) is mounted to the bottom of the cylinder block inside the engine oil pan (21). The engine oil pump (19) pulls oil from engine oil pan (21). The engine oil pump pushes the oil through the passage to the engine oil cooler (17). Oil then flows through engine oil filter (16). The filtered oil then enters the supply for the number 4 main bearing (11), turbocharger oil supply line (10), and main oil gallery (9). The supply for the number 4 main bearing (11) supplies oil to the number four camshaft bearing.The main oil gallery (9) distributes oil to main bearings (7), piston cooling jets (4), and camshaft bearings (8). Oil from main oil gallery (9) exits the front of the block. The oil then enters a groove that is cast in the front housing.Oil enters the crankshaft through holes in the bearing surfaces (journals) for the main bearing (7). Passages connect the bearing surface (journal) for the main bearing (7) with the bearing surface (journal) for the connecting rod.Oil supplied from the main oil gallery (9) is directed to cylinder head gallery (2) and through passage (1) to the rocker arm mechanism. Also, the oil is supplied to the oil supply line for the fuel pump (5) and oil supply line for the air compressor (6).Oil from the front main bearing enters a passage (12) to the camshaft idler gear bearing. Oil passages in the crankshaft send oil from all the main bearings (7) through the connecting rods to the connecting rod bearings.The passages send oil from the camshaft bearings (8) to an oil passage in the side covers. The oil then enters a hole in the shafts to pushrod lifters (3). The oil lubricates the bearings of the lifter.Note: Engines that are equipped with an auxiliary oil filter (18) will receive oil at a port. The filtered oil will be returned to engine oil pan (21).The oil circuit consists of a common pressure circuit. The pressure circuit typically operates at a pressure of 240 kPa (35 psi) to 480 kPa (70 psi). The pressure circuit provides engine oil that has been filtered to the lubricating system of the engine. Oil is drawn from the engine oil pan (21). Oil is supplied through the engine oil cooler (17) and engine oil filter (16) to the engine.After the lubrication oils work is done, the lubrication oil returns to the engine oil pan.The oil pump bypass valve