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5 - 2
Section 3
Routine Maintenance
9803/6020
Section 3
5 - 2
Issue 1
Hydraulics (continued)
Air Bleeding Procedures
After replacing the hydraulic oil or repairing or replacing
hydraulic components or removing hydraulic pipes, bleed
air from the hydraulic circuit.
Bleeding Air from the Hydraulic Pump
If the air is not completely bled, the life of the pump will be
reduced or serious trouble can occur.
1
Prepare the Machine
Position the machine on level ground. Stop the
engine.
Remove the starter key.
2
Locate the Hydraulic Pump
Refer to
Component Location Diagram
at the end of
this section.
3
Temporarily loosen air bleeding plug
A
.
4
If oil comes out, re-tighten the plug. If oil does not
come out, remove the air bleeding plug
A
and prime
the pump by pouring hydraulic oil into the pump case
through the air bleeding port.
5
Temporarily tighten air bleeding plug
A
. Start the
engine and idle at low speed. Slightly loosen air
bleeding plug
A
and continue to run the engine until
oil exudes from the air bleeding port.
6
Tighten the air bleeding plug firmly.
7
Stop the engine and allow any bubbles in the system
to make their
way through the hydraulic tank.
A
Air Bleeding Sequence
Air Bleeding
Air Bleeding Air Bleeding
from slew
Check
from pump
from ram
motor
Hydraulic oil or
pump replacement
O
O
O
O
Ram replacement
O
O
Slew motor
replacement
O
O
Summary of Contents for JS70
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Page 189: ...Section E Section E Hydraulics 9803 6020 Issue 1 33 4 33 4 Control Valves Control Valve 291360...