PLATE-PRESSURE 6E3402 - Caterpillar

Clean the area thoroughly in order to keep dirt out of the screen cover. Clean the area thoroughly in order to keep dirt out of the fill/vent plug.
Relieve the internal pressure from the hydraulic tank by loosening the fill/vent plug. After the pressure is relieved, remove the fill/vent plug.
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The oil drain valve is located under the hydraulic tank.
Remove the hydraulic tank access cover that is located under the upper structure. This will allow access to the drain valve.
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(4) Plug Note: Refer to Operation and Maintenance Manual, "General Hazard Information" for information on Containing Fluid Spillage.
Remove plug (4).
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(5) Pipe Nipple
(6) Hose
(7) Drain plug
Replace plug (4) with a 3B-7271 Pipe Nipple (5) and hose (6).
Loosen drain plug (7) in order to drain the oil.
Drain the oil into a suitable container.
After the oil has been drained, tighten drain plug (7) to a torque of 110 15 N m (81 11 lb ft).
Remove pipe nipple (5) and hose (6).
Clean plug (4) and install the plug. Tighten the plug to a torque of 75 5 N m (55 4 lb ft).
Open the access door on the right side of the machine.
Clean the pump, the hydraulic lines, and the hydraulic tank.
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Remove the plug from the tube, and allow the oil to drain into a container. Note: Dispose of used filters and used fluids according to local regulations.
Inspect the O-ring. Replace the O-ring if wear or damage is evident.
Clean the plug. Install the plug and the O-ring into the drain port.
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(8) Bolts
(9) Washers
(10) Cover
(11) Spring
(12) Screen
Remove bolts (8), washers (9), and cover (10). Note: Dispose of used filters and used fluids according to local regulations.Note: Do not allow spring (11) to fall back into the tank.
Remove spring (11) and screen (12). Note: Refer to Operation and Maintenance, "General Hazard Information" for information on Containing Fluid Spillage.
Wash the screen in a clean nonflammable solvent. Allow the screen to dry. Inspect the screen. Replace the screen, if the screen is damaged.
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(13) O-ring seal
(14) O-ring seal
Remove O-ring seal (13) from the screen.
Inspect O-ring seals (13) and (14). Replace the O-ring seals if wear or damage is evident.
Install O-ring seal (13) on screen (12).
Install screen (12) and spring (11). Then install cover (10), washers (9), and bolts (8). Note: Make sure that the O-ring seals and the spring are properly positioned during installation.
Fill the hydraulic system oil tank. Refer to Operation and Maintenance Manual, "Capacities (Refill)".
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Inspect the O-ring seal on the filler plug for damage. Replace the O-ring, if necessary. Clean the filler plug, and install the filler plug.
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(15) Drain hose
(16) Connector
(17) Seal
(18) Negative flow control hose Note: Do not attempt to start the engine until the pump has been filled with hydraulic oil. Serious damage to the hydraulic components can result.
When the hydraulic oil has been replaced, the air must be removed from the hydraulic oil system. To remove the air from the hydraulic oil system, follow Step 29.a through Step 29.g.
While the engine