COMMON AR 3856570 - Caterpillar

Illustration 1 g01192996
Main oil pump and lubrication system schematic (typical example)
(1) Main oil gallery
(2) Camshaft oil gallery
(3) Piston cooling jet gallery
(4) Piston cooling jet gallery
(5) Camshaft oil gallery
(6) Turbocharger oil supply
(7) Sequence valve
(8) Sequence valve
(9) Elbow
(10) Engine oil filter bypass valve
(11) Engine oil cooler
(12) Engine oil cooler bypass valve
(13) Engine oil relief valve
(14) Engine oil pump
(15) Elbow
(16) Suction bell
(17) Engine oil filter housing This system uses an engine oil pump (14) with three pump gears. The pump gears are driven by the front gear train. Oil is pulled from the pan through suction bell (16) and through elbow (15) by the engine oil pump. The suction bell has a screen in order to clean the engine oil.There is an engine oil relief valve (13) in the engine oil pump. The engine oil relief valve controls the pressure of the engine oil from the engine oil pump. The engine oil pump can put too much engine oil into the system. When there is too much engine oil, the engine oil pressure goes up and the relief valve opens. This action allows the engine oil that is not needed to go back to the inlet oil passage of the engine oil pump.The engine oil pump pushes engine oil through engine oil cooler (11) and through the engine oil filters to main oil gallery (1) and through camshaft oil gallery (2). Engine oil cooler (11) lowers the temperature of the engine oil before the engine oil is sent to the filters.Engine oil cooler bypass valve (12) allows engine oil to flow directly to the filters if the engine oil cooler becomes plugged. The engine oil cooler bypass valve also allows engine oil to flow directly to the filters if the engine oil becomes thick. The engine oil cooler bypass valve will bypass the engine oil to the filters above 180 20 kPa (26 3 psi) of oil pressure differential. Cartridge type filters are used. The filters are located in an engine oil filter housing. Cartridge type filters use a single bypass valve that is located in the engine oil filter housing.Clean engine oil from the filters flows through the engine oil line and into the block through elbow (9). Part of the engine oil flows to left camshaft oil gallery (2). The remainder of the engine oil flows to main oil gallery (1).Camshaft oil gallery (2) and camshaft oil gallery (5) are connected to each camshaft bearing by a drilled hole. The engine oil flows around each camshaft journal. The engine oil then travels through the cylinder head and through the rocker arm housing to the rocker arm shaft. A drilled hole connects the bores for the valve lifters to the oil hole for the rocker arm shaft. The valve lifters are lubricated at the top of each stroke.Main oil gallery (1) is connected to the main bearings by drilled holes. Drilled holes in the crankshaft connect the main bearing oil supply to the rod bearings. Engine oil from the