Komatsu PC450-8, Operation & Maintenance Manual

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OPERATION
MACHINE OPERATIONS AND CONTROLS
3-113
Check Oil Level in Hydraulic Tank, Add Oil
WARNING
q
The parts and oil are at high temperature immediately after the engine is stopped, and may cause
burns. Wait for the temperature to go down before starting the work.
q
When removing the oil filler cap, turn it slowly to release the internal pressure, then remove it.
1. Set the work equipment in the posture shown in the dia-
gram on the right, then check the oil level and add oil if
necessary.
2. If the work equipment is not in the condition shown in the
diagram on the right, start the engine, run the engine at low
speed, retract the arm and bucket cylinder rods fully, then
lower the boom, set the bucket teeth in contact with the
ground, and stop the engine.
3. Within 15 seconds after stopping the engine, move each
control lever (for work equipment and travel) to the full
stroke in all directions to release the internal pressure.
4. Check sight gauge (G). The oil level should be between the
H and L marks.
5. If the level is below the L mark, add oil through oil filler (F)
at the top of the hydraulic tank.
REMARK
The oil level will vary depending upon the oil temperature.
Accordingly, use the following as a guide:
Before starting operation: Between H and L levels
(Oil temperature 10 to 30°C)
Normal operation: Around H level
(Oil temperature 50 to 80°C)
NOTICE
Do not add oil above the H line. This will damage the
hydraulic circuit or cause the oil to spurt out.
If oil has been refilled, exceeding the H level, swing the
upper structure until drain plug (P) beneath the hydraulic
tank comes between the right and left track shoes and
stop the engine. Wait for the oil to cool down sufficiently,
then remove cover (1) and drain the excess oil through
drain plug (P).