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| Illustration 1 | g00827644 |
Lubrication system schematic | |
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| Illustration 2 | g00292619 |
Lubrication system components (1) Temperature regulator housing (2) Main engine oil gallery (3) Piston cooling jets (4) Drilled passage in the cylinder block from the main engine oil gallery to the camshaft bearings (5) Supply line for engine oil to the turbocharger (6) Turbochargers (7) Engine oil cooler (8) Drain lines for the engine oil from the turbochargers (9) Engine oil filters (10) Drilled passage in the cylinder block from the main engine oil gallery to the crankshaft main bearings (11) Valve for the engine oil filters (12) Priority valve (13) Suction tube (14) Prelube pump (15) Engine oil pump (16) Suction bell (17) Engine oil pan | |
Prelube pump (14) can be driven by an electric motor or an air motor. The prelube pump provides engine oil in order to lubricate the engine bearings before the engine is started and after the engine is shut down. The engine control will not allow the engine to start until the prelubrication has provided the minimum amount of lubrication to the engine. A check valve is located in the line between the prelube pump and the engine oil manifold. The check valve prevents pressurized engine oil from the engine oil pump from going through the prelube pump after the engine is started.
Engine oil pump (15) is mounted on the front left side of the front housing. The engine oil pump pulls engine oil from the pan through suction bell (16) and elbow (15). The suction bell has a screen in order to strain the engine oil.
The engine oil pump has a relief valve. If the pressure from the pump reaches 1000 kPa (145 psi), the relief valve opens and some of the engine oil returns to the engine oil pan. This helps prevent damage to the lubrication system components when the engine oil is cold.
Engine oil is pumped to the ports on the bypass valve of priority valve (12). If the pressure in the main oil gallery becomes excessive, the bypass valve opens in order to divert the engine oil back to the engine oil pan.
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| Illustration 3 | g00292624 |
(1) Temperature regulator housing (7) Engine oil coolers | |
The engine oil is pumped to temperature regulator housing (1). The temperature regulators and engine oil coolers (7) maintain the engine oil temperature. The core assemblies in the engine oil cooler are connected in parallel with the aftercooler. Water flows through the inside of the tubes in the bundle of the engine oil coolers. If the engine oil temperature is higher than 85 °C (185 °F), the flow is directed to the engine oil coolers. Engine oil flows from the engine oil coolers through valve (11) to engine oil filters (9) .
At cooler oil temperatures, the engine oil bypasses the engine oil coolers and the engine oil flows directly to the engine oil filters.
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| Illustration 4 | g00825761 |
(9) Engine oil filter housing (11) Valve for the engine oil filters | |
Each engine oil filter housing (9) contains three engine oil filter elements. Each housing has a port in order to purge air for draining and for filling.
Valve (11) allows the filter elements for each housing to be changed separately during engine operation.
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| Illustration 5 | g00292623 |
Engine oil flow through the cylinder block (2) Main engine oil gallery (3) Piston cooling jets (4) Drilled passage in the cylinder block between the main engine oil gallery and the camshaft bearings (10) Drilled passage in the cylinder block between the main engine oil gallery and the crankshaft main bearings (18) Camshaft bearing (19) Rocker arm assembly (20) Drilled passage in the cylinder block between the camshaft bearings and the cylinder head (21) Tube (22) Gallery for the piston cooling jets | |
The engine oil flows from the engine oil filters through priority valve (12) into main engine oil gallery (2) and gallery (22) for the piston cooling jets.
Main engine oil gallery (2) is connected to the crankshaft main bearings by drilled passage (10) in the cylinder block. Drilled holes in the crankshaft supply engine oil to the connecting rod bearings.
When the pressure in the system reaches 140 kPa (20 psi), priority valve (12) admits the engine oil to gallery (22) for the piston cooling jets. The priority valve will not allow engine oil into the gallery until there is pressure in main engine oil gallery (2). This reduces the amount of time that is necessary for the pressure to build up during start-up. The priority valve also helps maintain pressure at low idle speed.
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| Illustration 6 | g00292627 |
(3) Piston cooling jet | |
Piston cooling jet (3) is located in the engine block below each piston. Each piston cooling jet has two tubes with open ends. One tube distributes engine oil to an opening in the bottom of the piston for an engine oil gallery in the piston. This gallery provides engine oil to a manifold behind the ring band of the piston. The manifold provides engine oil to a slot (groove) in the side of both piston pin bores. The other tube directs engine oil to the center of the piston. This provides lubrication to the piston pin and the piston undercrown. This also helps cool the piston.
The camshaft bearings receive engine oil from main engine oil gallery (2) through drilled passages (4) in the cylinder block. The engine oil lubricates each camshaft bearing (18).
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| Illustration 7 | g00292626 |
(21) Tube (23) Valve lifter guide | |
Engine oil from the camshaft bearing flows through a drilled passage in the cylinder block to valve lifter guide (23) and tube (21) .
Tube (21) connects the valve lifter guide with passage (20). Engine oil flows through the tube and the passage to the cylinder head and rocker arm assembly (19) .
Supply line (5) provides engine oil for lubrication of the turbocharger bearings. The engine oil flows to the flywheel housing through drain lines (8) .
Engine oil is pumped to the front and the rear gear groups through tubes and drilled passages in the front housing and the rear housings.
After the lubrication is completed, the engine oil returns to the engine oil pan.