Komatsu PC2000-8 BACKHOE, Operation & Maintenance Manual

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PRECAUTIONS WHEN DISASSEMBLING MACHINE
LOADING SHOVEL
7-12
PRECAUTIONS WHEN DISASSEMBLING MACHINE 7
RELEASING PRESSURE 7
When disassembling the machine or removing the piping during inspection or maintenance, always release the
pressure as follows.
Releasing Pressure from Work Equipment Circuit, Swing Circuit, Travel Circuit 7
WARNING
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The hydraulic system is always under internal pressure, so when inspecting or replacing the piping or
hoses, always release the pressure in the circuit before starting. If the pressure is not released, high
pressure oil may spurt out and cause serious personal injury.
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The parts and oil are at high temperature after the engine is stopped, and may cause serious burns.
Wait for the temperature to go down before starting the operation.
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When the oil filler cap is removed, oil may spurt out, so turn the cap slowly to release the pressure
before removing the cap.
1. Stop the machine on firm horizontal ground, lower the work
equipment to the ground as shown in the diagram on the
right, then stop the engine.
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Set the lock lever to FREE position.
2. Operate each work equipment control lever to the full
stroke within 5 - 6 seconds after stopping the engine.
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Leave the starting switch at the ON position.
3. Remove the cap of the hydraulic tank.
4. Start the engine, run for approx. 10 seconds, then stop the engine again.
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Do not run the engine at more than 1000 rpm.
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Set the work equipment control levers to the HOLD position.
5. Operate each work equipment control lever to the full stroke within 5 - 6 seconds after stopping the engine.
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Repeat Steps 4 - 5 three times.
Releasing Pressure in Accumulator Circuit 7
After stopping the engine, set lock lever (1) to the FREE posi-
tion (F), then operate each work equipment control lever 3 - 4
times to the end of the stroke. After 1 minute, the internal pres-
sure will be relieved.
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Do not loosen any piping until at least 1 minute has passed
after relieving the internal pressure.