DX380LC-7
Inspection, Maintenance and Adjustment
4-100
Venting and Priming Hydraulic
System
Main System Pump
NOTE:
If pump is run without sufficient oil in the main
hydraulic pump, damage can occur. Always vent
pump of air after draining hydraulic system.
1.
With the engine stopped, remove vent plug (Figure 139) to
see if any oil is present.
2.
If oil is not present, fill oil tank with oil.
3.
Install vent plug (Figure 139) first.
4.
Slowly loosen vent plug (Figure 139) several turns, until
hydraulic oil flows out of plug. This shows that air has been
released.
5.
Tighten the plug (Figure 139).
Hydraulic Cylinders
1.
Run engine at "LOW IDLE". Extend and retract each
cylinder to within 100 mm (4 in) of fully stroking it 4 - 5
times.
2.
Operate fully extend and retract each cylinder 3- 4 times.
3.
Repeat procedure until cylinders extend and retract
smoothly.
Figure 139
DS1901882
NOTICE
If cylinders are operated in "HIGH IDLE" after the hydraulic
system has been drained or the cylinder has been rebuilt,
damage to piston packing and seals can occur. Always vent
air from cylinders at "LOW IDLE" and at a slow speed.
