Bleeding Air From Each Part - Komatsu Galeo PC138US-8 Shop Manual

SEN02458-01

Bleeding air from each part

Air bleeding item
Contents of work
• Replacing hydraulic oil
• Cleaning strainer
• Replacing return filter element
• Replacing and repairing hydraulic
pump
• Removing suction piping
• Replacing and repairing control
valve
• Removing control valve piping
• Replacing and repairing cylinder
• Removing cylinder piping
• Replacing and repairing swing
motor
• Removing swing motor piping
• Replacing and repairing travel
motor
• Removing travel motor piping
• Replacing and repairing swivel joint
• Removing swivel joint piping
Note: Bleed air from the swing motor and travel motor only when the oil in the motor cases is drained.
1. Bleeding air from hydraulic pump
1) Loosen air bleeder (1) and check that oil
oozes out through the air bleeder.
2) After the oil oozes out, tighten air bleeder
(1).
3
Air bleeder:
7.8 – 9.8 Nm {0.8 – 1.0 kgm}
a Do not use an impact wrench to
tighten the air bleeder.
50
1
1 2
Bleeding air
from Starting
hydraulic engine
pump
q q
q
q q
q
q
q
q
q
2.
3.
30 Testing and adjusting
Air bleeding procedure
3 4
Bleeding air
Bleeding air
from swing
from cylinder
motor
q
q
(See note)
o o
q o
q o
q o
o q
o o
o o
Starting engine
When running the engine after performing step
1, keep its speed at low idle for 10 minutes.
a If the engine coolant temperature is low
and the automatic warm-up operation is
started, stop the engine temporarily and
reset the automatic warm-up operation
with the fuel control dial (Set the starting
switch in the ON position and hold the fuel
control dial in the MAX position for 3 sec-
onds, and the automatic warm-up opera-
tion is reset).
Bleeding air from cylinder
a If a cylinder is replaced, bleed air from it
before connecting the work equipment. In
particular, the boom cylinder does not
move to the lowering stroke end, if it is
installed to the work equipment.
1) Run the engine at low idle for about 5 min-
utes.
2) While running the engine at low idle, raise
and lower the boom 4 – 5 times.
a Stop the piston rod about 100 mm
b efo re e ac h s tr ok e en d. Do no t
relieve the oil.
5 6
Checking oil
Bleeding air
level and
from travel
starting
motor
operation
q
q
(See note)
o q
o q
o q
o q
o q
q q
o q
PC138US, USLC-8