Hitachi Zaxis 200 Workshop Manual page 40

GENERAL / Precautions for Disassembling and Assembling
•
Precautions for Assembling
• Be sure to clean all parts and inspect them for
any damage. If any damage is found, repair or
replace part.
• Dirt or debris on the contact or sliding surfaces
may shorten the service life of the machine. Take
care not to contaminate any contact or sliding
surfaces.
• Be sure to replace O-rings, backup rings, and oil
seals with new ones once they are disassembled.
Apply a film of grease before installing.
• Be sure that liquid-gasket-applied surfaces are
clean and dry.
• If an anti-corrosive agent has been used on a
new part, be sure to thoroughly clean the part to
remove the agent.
• Utilize matching marks when assembling.
• Be sure to use the designated tools to assemble
bearings, bushings and oil seals.
• Keep a record of the number of tools used for
disassembly/assembly.
complete, count the number of tools, so as to
make sure that no forgotten tools remain in the
assembled machine.
After assembling
W1-1-2
Bleeding Air from Hydraulic System
When hydraulic oil is drained, the suction filter or the
suction lines are replaced, or the removal and in-
stallation of the pump, swing motor, travel motor or
cylinder is done, bleed air from the hydraulic system
in the following procedures:
IMPORTANT: If the engine is started with air
is
•
Bleeding Air from Hydraulic Pump
• Remove the air bleeding plug from the top of the
pump and fill the pump housing with hydraulic oil.
• After the pump housing is filled with hydraulic oil,
temporarily tighten the plug. Then, start the en-
gine and run at slow idle speed.
• Slightly loosen the plug to bleed air from the
pump housing until hydraulic oil oozes out.
• After bleeding all the air, securely tighten the
plug.
•
Bleeding Air from Travel Motor / Swing Motor
• With the drain plug / hose on travel motor / swing
motor removed, fill the motor case with hydraulic
oil.
trapped in the hydraulic pump hous-
ing, damage to the pump may result.
If the hydraulic motor is operated
with air trapped in the hydraulic
motor housing, damage to the mo-
tor may result.
If the cylinder is operated with air
trapped in the cylinder tube, dam-
age to the cylinder may result.
Be sure to bleed air before starting
the engine.