Lubrication System Components
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| Illustration 1 | g00562119 |
Lubrication system components (typical example) (1) Oil supply line (2) Oil return line (3) Oil cooler (4) Oil filter (5) Oil pan | |
The lubrication system has the following components:
- oil pan
- oil pump
- oil cooler
- oil filter
- turbocharger oil lines
- oil passages for the cylinder block
Oil Flow Through The Oil Filter And Oil Cooler
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| Illustration 2 | g00562123 |
Oil flow when the engine is warm. (1) Oil manifold (2) Oil supply line (3) Oil return line (4) Oil filter (5) Bypass valve for the oil filter (6) Oil pan (7) Oil pump (8) Bypass valve for the oil cooler (9) Suction lines (10) Oil cooler (11) Bypass valve for the oil pump | |
When the engine is warm, oil comes from the oil pan (6) through the suction lines (9) to the oil pump (7). The oil pump sends hot oil to the oil cooler (10). The oil is then sent to the oil filter (4). Oil from the oil filter is sent to the oil manifold (1) in the cylinder block and to the oil supply line (2) for the turbocharger. Oil from the turbocharger goes back through the oil return line (3) to the oil pan.
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| Illustration 3 | g00562383 |
Oil flow when the engine Is cold. (1) Oil manifold (2) Oil supply line (3) Oil return line (4) Oil filter (5) Bypass valve for the oil filter (6) Oil pan (7) Oil pump (8) Bypass valve for the oil cooler (9) Suction lines (10) Oil cooler (11) Bypass valve for the oil pump | |
When the engine is cold, oil comes from the oil pan (6) through the suction lines (9) to the oil pump (7). When the oil is cold, an oil pressure difference in the bypass valves also causes the bypass valves to open. These bypass valves then provide immediate lubrication to all of the engine components when cold oil with high viscosity causes a restriction to the oil flow through the oil cooler (10) and the oil filter (4). The oil pump then sends the cold oil through the bypass valve (8) for the oil cooler and through the bypass valve (5) for the oil filter. The oil then goes to the oil manifold (1) in the cylinder block and to the supply line (2) for the turbocharger. Oil from the turbocharger goes back through the oil return line (3) to the oil pan.
When the oil is warm, an oil pressure difference in the bypass valves also causes the bypass valves to close. There is normal oil flow through the oil cooler and the oil filter.
The bypass valves will also open when there is a restriction in the oil cooler or the oil filter. This prevents a restricted oil filter or a restricted oil cooler from stopping the lubrication of the engine. The system pressure is limited by the oil pump bypass valve (11) .
Oil Flow In The Engine
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| Illustration 4 | g00431790 |
Engine oil flow schematic (1) Rocker arm shaft (2) Oil passage to air compressor (3) Camshaft bearing journals (4) Oil passage to adjustable idler gear (5) Oil passage to the fixed idler stub shaft (6) Oil passage to cluster idler gear (7) Oil manifold (8) Piston cooling jet (9) Crankshaft main bearings (10) Oil passage from filter | |
The oil from the oil manifold (7) is sent under pressure through drilled passages to the crankshaft main bearings (9). The oil flows through drilled holes in the crankshaft. This oil lubricates the connecting rod bearings. A small amount of oil is sent through the piston cooling jets (8). The piston cooling jets cool the pistons.
Oil flows through passages in the timing gear housing and the accessory drive gear. This oil flows to the air compressor through the oil passage (2) .
Oil passage (4) provides oil to the adjustable idler gear. Oil passage (5) provides oil to the fixed idler gear. Oil passage (6) provides oil to the cluster gear. The oil flows through a passage in the shafts of the gears. This lubrication helps to ensure a long life for the front gear group.
There is a pressure control valve in the oil pump. This valve controls the pressure of the oil that flows from the oil pump. The oil pump supplies a greater quantity of oil into the system. This extra quantity of oil is not needed by the system. The extra quantity of oil will cause the pressure to rise and the valve will open. This allows the oil that is not needed to go back to the inlet oil passage of the oil pump.
Oil passage (9) provides lubrication to the rear crankshaft seal. This ensures a long service life for the rear crankshaft seal.
Oil flows into the cylinder head via a hollow locating dowel in the top deck of the cylinder block. Oil travels to the camshaft bearing journals (3) and the three center rocker arm shaft supports through drilled passages in the cylinder head. The supports supply oil to each rocker shaft. Oil flows to the bushings of the fuel injector rocker arm through holes in the rocker arm shaft (1). This same oil lubricates the valve and the rollers. Oil flows through drilled passages in the rocker arms. This oil lubricates the roller, the valve bridge and the contact surfaces of the actuator of the unit injector. Splash oil lubrication is used to lubricate other components of the valve system.
When all the components are lubricated the excess oil returns to the engine oil pan.