Hitachi ZX 870-6 Instruction manual

ZX
WJBL40-EN-00
ZX870-6 •870LC-6 •890H-6 •890LCH-6 •890R-6 •890LCR-6
HYDRAULIC EXCAVATOR WORKSHOP MANUAL
PRINTED IN JAPAN (K) 2017, 03
WJBL40-EN-00
PART NO.
Workshop Manual
URL:http://www.hitachi-c-m.com
Hydraulic Excavator
870-6
870LC-6
890H-6
890LCH-6
890R-6
890LCR-6
Service Manual consists of the following separate Part No.
Technical Manual (Operational Principle) : Vol. No.TOJBL40-EN
Technical Manual (Troubleshooting) : Vol. No.TTJBL40-EN
Workshop Manual : Vol. No.WJBL40-EN
Engine Manual : Vol. No.ETJBL40-EN, EWJBL40-EN

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Group 1 Precautions for Disassembling and
Assembling
Precautions for Disassembling and
Assembling.................................................................W1-1-1-1
Group 2 Tightening
Tightening Bolts and Nuts..........................................W1-2-1-1
Piping Joint ......................................................................W1-2-1-4
Group 3 Painting
Painting .............................................................................W1-3-1-1
Group 4 Bleeding Air
Bleeding Air from Hydraulic System .......................W1-4-1-1
Bleeding Air from Fuel System..................................W1-4-1-2
Air Bleeding from the Diesel Exhaust Fluid
Defrosting Piping .....................................................W1-4-1-4
Group 5 Preparation
Preparation before Inspection and
Maintenance ..............................................................W1-5-1-1
Hydraulic Circuit Pressure Release Procedure.....W1-5-1-3
Pressure Release from Hydraulic Oil Tank .............W1-5-1-4
Pressure Release from Expansion Tank .................W1-5-1-5
SECTION 1
GENERAL
CONTENTS
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Group 1 Upperstructure
Pump Device ...................................................................W2-1-1-1
Swing Motor ....................................................................W2-1-2-1
Group 2 Undercarriage
Travel Motor.....................................................................W2-2-1-1
Sprocket ............................................................................W2-2-1-3
Center Joint......................................................................W2-2-2-1
Front Idler .........................................................................W2-2-3-1
Upper Roller.....................................................................W2-2-4-1
Lower Roller .....................................................................W2-2-4-2
Track....................................................................................W2-2-5-1
Group 3 Front Attachment
Pin and Bushing..............................................................W2-3-1-1
Side Cutter........................................................................W2-3-1-3
Point....................................................................................W2-3-1-4
Standard Dimensions for Arm and Bucket
Connection .................................................................W2-3-1-5
Standard Dimensions for Arm and Boom
Connection .................................................................W2-3-1-7
Cylinder .............................................................................W2-3-2-1
SECTION 2
MAINTENANCE STANDARD
CONTENTS
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Group 1 Cab
Removal and Installation of Cab ..............................W3-1-1-1
Dimensions of Cab Glass (Standard Cab)..............W3-1-2-1
Dimensions of Cab Glass (H Cab).......................... W3-1-2-20
Group 2 Counterweight
Removal and Installation of Counterweight........W3-2-1-1
Group 3 Main Frame
Removal and Installation of Main Frame...............W3-3-1-1
Group 4 Engine
Removal and Installation of Engine ........................W3-4-1-1
Group 8 Pump Device
Removal and Installation of Pump Device............W3-8-1-1
Disassembly of Pump Transmission........................W3-8-2-1
Assembly of Pump Transmission..............................W3-8-2-5
Disassembly of Main Pump........................................W3-8-3-1
Assembly of Main Pump..............................................W3-8-3-6
Disassembly of Regulator for Main Pump.............W3-8-4-1
Assembly of Regulator for Main Pump .................W3-8-4-4
Disassembly of Fan Pump...........................................W3-8-5-1
Assembly of Fan Pump ................................................W3-8-5-5
Disassembly of Regulator for Fan Pump................W3-8-6-1
Assembly of Regulator for Fan Pump .....................W3-8-6-3
Structure of Pilot Pump ...............................................W3-8-7-1
Group 9 Control Valve
Removal and Installation of Control Valve............W3-9-1-1
Disassembly and Assembly of Housing.................W3-9-2-1
Disassembly of Control Valve 4-Spool Side ..........W3-9-3-1
Assembly of Control Valve 4-Spool Side................W3-9-3-9
Disassembly of Control Valve 5-Spool Side ..........W3-9-4-1
Assembly of Control Valve 5-Spool Side................W3-9-4-8
Group 10 Swing Device
Removal and Installation of Swing Device ........ W3-10-1-1
Disassembly of Swing Reduction Gear ...............W3-10-2-1
Assembly of Swing Reduction Gear.....................W3-10-2-7
Disassembly of Swing Motor..................................W3-10-3-1
Assembly of Swing Motor........................................ W3-10-3-4
Structure of Swing Parking Brake Selection
Valve...........................................................................W3-10-4-1
Group 11 Pilot Valve
Removal and Installation of Pilot Valve (Left) ... W3-11-1-1
Removal and Installation of Pilot Valve
(Right) ........................................................................ W3-11-2-1
Removal and Installation of Travel Pilot
Valve...........................................................................W3-11-3-1
Disassembly of Pilot Valves (Right and Left) .....W3-11-4-1
Assembly of Pilot Valves (Right and Left) ........... W3-11-4-4
Disassembly of Travel Pilot Valve........................... W3-11-5-1
Assembly of Travel Pilot Valve ................................W3-11-5-5
Group 12 Solenoid Valve
Removal and Installation of Pilot Shut-Off
Solenoid Valve ........................................................W3-12-1-1
Removal and Installation of 4-Spool Solenoid
Valve Unit ................................................................. W3-12-2-1
Removal and Installation of 2-Spool Solenoid
Valve Unit ................................................................. W3-12-3-1
Disassembly of Pilot Shut-Off Solenoid
Valve...........................................................................W3-12-4-1
Assembly of Pilot Shut-Off Solenoid Valve........ W3-12-4-3
Structure of 4-Spool Solenoid Valve Unit...........W3-12-5-1
Structure of 2-Spool Solenoid Valve Unit...........W3-12-6-1
Group 13 Signal Control Valve
Removal and Installation of Signal Control
Valve...........................................................................W3-13-1-1
Structure of Signal Control Valve .......................... W3-13-2-1
Group 14 Aftertreatment Device
Removal and Installation of Aftertreatment
Device........................................................................W3-14-1-1
Group 15 DEF Tank
Removal and Installation of DEF Tank.................W3-15-1-1
Group 16 Coolant Control Valve
Removal and Installation of Coolant Control
Valve...........................................................................W3-16-1-1
Group 17 DEF Supply Module
Removal and Installation of DEF Supply
Module......................................................................W3-17-1-1
Group 19 Fan Valve
Removal and Installation of Oil Cooler Fan
Valve...........................................................................W3-19-1-1
Removal and Installation of Radiator Fan
Valve...........................................................................W3-19-2-1
Structure of Oil Cooler Fan Valve and Radiator
Fan Valve...................................................................W3-19-3-1
SECTION 3
UPPERSTRUCTURE
CONTENTS
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Group 20 Fan Motor
Removal and Installation of Oil Cooler Fan
Motor .........................................................................W3-20-1-1
Removal and Installation of Radiator Fan
Motor .........................................................................W3-20-2-1
Structure of Oil Cooler Fan Motor and
Radiator Fan Motor............................................... W3-20-3-1
Group 21 Shockless Valve
Removal and Installation of Shockless Valve.... W3-21-1-1
Structure of Shockless Valve................................... W3-21-2-1
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Group 1 Swing Bearing
Removal and Installation of Swing Bearing .........W4-1-1-1
Disassembly of Swing Bearing..................................W4-1-2-1
Assembly of Swing Bearing........................................W4-1-2-4
Group 2 Travel Device
Removal and Installation of Travel Device............W4-2-1-1
Disassembly of Travel Device.....................................W4-2-2-1
Assembly of Travel Device ..........................................W4-2-2-9
Disassembly of Travel Motor......................................W4-2-3-1
Assembly of Travel Motor............................................W4-2-3-6
Disassembly of Brake Valve ........................................W4-2-4-1
Assembly of Brake Valve..............................................W4-2-4-4
Precautions for Using Floating Seal.........................W4-2-5-1
Group 3 Center Joint
Removal and Installation of Center Joint ..............W4-3-1-1
Disassembly of Center Joint.......................................W4-3-2-1
Assembly of Center Joint ............................................W4-3-2-3
Replacement of Body and Spindle ..........................W4-3-2-6
Group 4 Track Adjuster
Removal and Installation of Track Adjuster..........W4-4-1-1
Disassembly of Track Adjuster...................................W4-4-2-1
Assembly of Track Adjuster ........................................W4-4-2-6
Group 5 Front Idler
Removal and Installation of Front Idler..................W4-5-1-1
Disassembly of Front Idler ..........................................W4-5-2-1
Assembly of Front Idler................................................W4-5-2-4
Precautions for Using Floating Seal.........................W4-5-3-1
Group 6 Upper and Lower Rollers
Removal and Installation of Upper Roller .............W4-6-1-1
Removal and Installation of Lower Roller .............W4-6-2-1
Disassembly of Lower Roller......................................W4-6-3-1
Assembly of Lower Roller............................................W4-6-3-3
Precautions for Using Floating Seal.........................W4-6-4-1
Group 7 Track
Removal and Installation of Track............................W4-7-1-1
SECTION 4
UNDERCARRIAGE
CONTENTS
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Group 1 Front Attachment
Removal and Installation of Bucket.........................W5-1-1-1
Removal and Installation of Arm..............................W5-1-2-1
Removal and Installation of Boom ..........................W5-1-3-1
Removal and Installation of Bushing......................W5-1-4-1
Group 2 Cylinder
Removal and Installation of Boom Cylinder.........W5-2-1-1
Removal and Installation of Arm Cylinder............W5-2-2-1
Removal and Installation of Bucket Cylinder.......W5-2-3-1
Disassembly of Boom, Arm, and Bucket
Cylinders......................................................................W5-2-4-1
Assembly of Boom, Arm, and Bucket
Cylinders......................................................................W5-2-4-7
SECTION 5
FRONT ATTACHMENT
CONTENTS

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INTRODUCTION
IN-1
To The Reader
Additional References
Manual Composition
Page Number
Trademark
This manual is written for an experienced technician to
provide technical information needed to maintain and
repair this machine.
The machine specification and description according to
destination may be explained on this manual.
Be sure to thoroughly read this manual for correct
product information and service procedures.
Please refer to the other materials (operator’s manual,
parts catalog, engine technical material and Hitachi
training material etc.) in addition to this manual.
This manual consists the Technical Manual, the Workshop
Manual and the Engine Manual.
Information included in the Technical Manual:
Technical information needed for redelivery and delivery,
operation and activation of all devices and systems,
operational performance tests, and troubleshooting
procedures.
Each page has a number, located on the center lower part
of the page, and each number contains the following
information:
Example:
Technical Manual: T 1-3-5
T Technical Manual
1 Section Number
3 Group Number
5 Consecutive Page Number for Each Group
AdBlue® is a registered trademark of the Verband der
Automobilindustrie e.V. (VDA).
If you have any questions or comments, at if you found
any errors regarding the contents of this manual,
please contact using “Service Manual Revision Request
Form”at the end of this manual. (Note: Do not tear off
the form. Copy it for usage.):
Technical Information Center Hitachi Construction
Machinery Co., Ltd.
TEL: [phone]
FAX: [phone]
E-mail: [e-mail]
Information included in the Workshop Manual:
Technical information needed for maintenance and
repair of the machine, tools and devices needed for
maintenance and repair, maintenance standards, and
removal / installation and assemble / disassemble
procedures.
Information included in the Engine Manual:
Technical information needed for redelivery and delivery
and maintenance and repair of the machine, operation
and activation of all devices and systems, troubleshooting
and assemble / disassemble procedures.
Workshop Manual: W 1-3-2-5
W Workshop Manual
1 Section Number
3 Group Number
2 Sub Group Number
5 Consecutive Page Number for Each Group

INTRODUCTION
IN-2
Safety Alert Symbol and Headline Notations
In this manual, the following safety alert symbol and
signal words are used to alert the reader to the potential
for personal injury of machine damage.
dThis is the safety alert symbol. When you see this
symbol, be alert to the potential for personal injury.
Never fail to follow the safety instructions prescribed
along with the safety alert symbol.
The safety alert symbol is also used to draw attention to
component/part weights.
To avoid injury and damage, be sure to use appropriate
lifting techniques and equipment when lifting heavy
parts.
dCAUTION:
Indicates potentially hazardous situation which could, if
not avoided, result in personal injury or death.
IMPORTANT:
Indicates a situation which, if not conformed to the
instructions, could result in damage to the machine.
fNOTE:
Indicates supplementary technical information or know-
how.
Units Used
Quantity To Convert From Into Multiply By
Length mm in 0.03937
mm ft 0.003281
Volume L US gal 0.2642
L US qt 1.057
m3yd31.308
Weight kg lb 2.205
Force N kgf 0.10197
N lbf 0.2248
Torque N·m kgf·m 0.10197
Pressure MPa kgf/cm210.197
MPa psi 145.0
Power kW PS 1.360
kW HP 1.341
Temperature °C °F °C×1.8+32
Velocity km/h mph 0.6214
min-1 rpm 1.0
Flow rate L/min US gpm 0.2642
mL/rev cc/rev 1.0
SI Units (International System of Units) are used in this
manual.
A table for conversion from SI units to other system units
is shown below for reference purposes.

SYMBOL AND ABBREVIATION
SY-1
Symbol /
Abbreviation
Name Explanation
TO Technical manual (Operational principle) Technical manual (Operational Principle).
TT Technical manual (Troubleshooting) Technical manual (Troubleshooting).
T/M Technical manual Technical manual.
W, W/M Workshop manual Workshop manual (Removal and Installation, Disassembly
and Assembly).
MC Main Controller Main controller. MC controls the engine, pump, and valve
according to the machine operating condition.
ECM Engine Control Module Engine controller. ECM controls fuel injection amount
according to the machine operating condition.
VGS Variable Geometry System controller Variable turbo controller. VGS is an exhaust turbo charged
system to supercharge the exhaust energy while running
the engine at slow idle speed. VGS optimizes the turbine
rotation, improves the performance at slow-speed torque
and the acceleration, reduces fuel consumption, and reduces
particulate matter (PM) by adjusting the nozzle opening of
turbine housing.
GSM Global System for Mobile communications
controller
Communication controller. GSM is a type of wireless
communication system, is used in more than on 100
countries around Europe and Asia, and becomes the factual
global standards of the mobile telephone.
GPS Global Positioning System Global positioning system.
CAN Controller Area Network CAN communication. CAN is a serial communications
protocol internationally-standardized by ISO (International
Organization for Standardization).
A/C Air Conditioner Air conditioner.
OP, OPT Option Optional component.
MPDr. Maintenance Pro Dr. MPDr. is software that troubleshooting, monitoring, and
adjustment.
A/I Auto-Idle Auto-idle.
WU Warming-Up Warming-up.
Li Low (Slow) Idle Slow idle engine speed.
ATT Attachment Attachment. Attachment is optional parts such as breaker,
crusher, and pulverizer in this manual.
HI, Hi High Travel fast position.
LO, Lo Low Travel slow position.

SYMBOL AND ABBREVIATION
SY-2
Symbol /
Abbreviation
Name Explanation
DPF Diesel Particulate Filter DPF is a filter which removes particulate matter (PM)
including the toxic substance of exhaust gas of the diesel
engine. Exhaust particulate removal equipment.
DPD Diesel Particulate Diffuser DPD is an exhaust emission control system, a type of DPF,
which cleans up particulate matter (PM) of diesel engine
exhaust gas. DPD is a ceramic filter which traps and filters
PM of exhaust gas. DPD burns up accumulated PM when PM
increases and regenerates the filter.
DOC Diesel Oxidation Catalyst Oxidation catalyst for the diesel engine. Diesel oxidation
catalyst oxidizes unburnt fuel and raises exhaust
temperature.
CSF Catalyzed Soot Filter Filter. The filter traps, burns, and remove particulate matter
(PM) by using high-temperature-exhaust gas with diesel
oxidation catalyst. Catalyst is applied onto the filter. This
advances PM burning.
PM Particulate Matter Particulate matter.
EGR Exhaust Gas Recirculation The EGR control re-circulates a part of exhaust gas in the
intake manifold and combines it with intake-air. Therefore,
combustion temperature is lowered and generation of oxide
of nitrogen (NOx) is controlled.
HRV Hose Rupture Valve Hose rupture valve.
LLC Long Life Coolant Long life coolant.
SCR Selective Catalytic Reduction The urea SCR system injects diesel exhaust fluid to nitrogen
oxide (NOx) exhausted from the engine and purifies NOx.
DCU Dosing Control Unit Urea SCR system controller. DCU controls the diesel exhaust
fluid injection amount according to the machine operating
condition.
S/M Supply Module Diesel exhaust fluid supply module. The diesel exhaust fluid
supply module pumps diesel exhaust fluid to the dosing
module (D/M). Then, it returns diesel exhaust fluid in the
diesel exhaust fluid circuit when the key switch is turned
OFF.
D/M Dosing Module Dosing module. The dosing module (D/M) injects diesel
exhaust fluid into the exhaust piping according to the signal
from DCU.
NOx Nitrogen Oxide Nitrogen oxide.
DEF Diesel Exhaust Fluid Diesel exhaust fluid. The diesel exhaust fluid concentration is
32.5 %, which is specified in ISO22241.

SA-1
SAFETY
SA-688
SA-1223
Recognize Safety Information
These are the SAFETY ALERT SYMBOLS.
When you see these symbols on your machine or in this
manual, be alert to the potential for personal injury.
Follow recommended precautions and safe operating
practices.
Understand Signal Words
On machine safety signs, signal words designating the
degree or level of hazard - DANGER, WARNING, or CAUTION
- are used with the safety alert symbol.
DANGER indicates an imminently hazardous situation
which, if not avoided, will result in death or serious injury.
WARNING indicates a potentially hazardous situation
which, if not avoided, could result in death or serious
injury.
CAUTION indicates a potentially hazardous situation
which, if not avoided, may result in minor or moderate
injury.
DANGER or WARNING safety signs are located near
specific hazards. General precautions are listed on
CAUTION safety signs.
Some safety signs are occasionally used on this machine
that do not use any of the designated signal words
mentioned above after the safety alert symbol.
CAUTION also calls attention to safety message in this
manual.
To avoid confusing machine protection with personal safety
messages, a signal word IMPORTANT indicates a situation
which, if not avoided, could result in damage to the
machine.
fNOTE: Indicates an additional explanation for a piece of
information.

SAFETY
SA-2
SA-003
Follow Safety Instructions
Carefully read and follow all safety signs on the machine
and all safety messages in the operator's manual.
Safety signs should be installed, maintained and replaced
when necessary.
If a safety sign or operator's manual is damaged or
missing, order a replacement from your authorized dealer
in the same way you order other replacement parts (be
sure to state machine model and serial number when
ordering).
Learn how to operate the machine and its controls correctly
and safely.
Allow only trained, qualified, authorized personnel to
operate the machine.
Keep your machine in proper working condition.
Unauthorized modifications of the machine may impair
its function and/or safety and affect machine life.
Do not modify any machine parts without authorization.
Failure to do so may deteriorate the safety, function, and/
or service life of the part. In addition, personal accident,
machine trouble, and/or damage to material caused by
unauthorized modifications will void Hitachi Warranty
Policy.
Never attempt to modify or disassemble the inlet/exhaust
parts and the aftertreatment device. Avoid shocks to the
element of the aftertreatment device, such as striking
or dropping objects onto the element. Failure to do so
may affect the exhaust gas purifying device, possibly
damaging it or lowering its performance.
Do not use attachments and/or optional parts or
equipment not authorized by Hitachi. Failure to do so
may deteriorate the safety, function, and/or service life
of the machine. In addition, personal accident, machine
trouble, and/or damage to material caused by using
unauthorized attachments and/or optional parts or
equipment will void Hitachi Warranty Policy.
The safety messages in this SAFETY chapter are intended
to illustrate basic safety procedures of machines. However
it is impossible for these safety messages to cover every
hazardous situation you may encounter. If you have any
questions, you should first consult your supervisor and/
or your authorized dealer before operating or performing
maintenance work on the machine.

SAFETY
SA-3
SA-437
SA-438
Prepare for Emergencies
Be prepared for a fire or an accident.
Keep a first aid kit and fire extinguisher on hand.
Thoroughly read and understand the label attached on
the fire extinguisher to use it properly.
To ensure that a fire extinguisher can be always used
when necessary, check and service the fire extinguisher
at the recommended intervals as specified in the fire
extinguisher manual.
Establish emergency procedure guidelines to cope with
fires and accidents.
Keep emergency numbers for doctors, ambulance
service, hospital, and fire department posted near your
telephone.
Wear Protective Clothing
Wear close fitting clothing and safety equipment
appropriate to the job.
You may need:
A hard hat
Safety shoes
Safety glasses, goggles, or face shield
Heavy gloves
Hearing protection
Reflective clothing
Wet weather gear
Respirator or filter mask
Be sure to wear the correct equipment and clothing for the
job. Do not take any chances.
Avoid wearing loose clothing, jewelry, or other items that
can catch on control levers or other parts of the machine.
Operating equipment safely requires the full attention of
the operator. Do not wear radio or music headphones while
operating the machine.

SAFETY
SA-4
SA-435
Protect Against Noise
Prolonged exposure to loud noise can cause impairment or
loss of hearing.
Wear a suitable hearing protective device such as
earmuffs or earplugs to protect against objectionable or
uncomfortably loud noises.
Inspect Machine
Inspect your machine carefully each day or shift by walking
around it before you start it to avoid personal injury.
In the walk-around inspection be sure to cover all points
described in the "Inspect Machine Daily Before Starting"
section in the operator’s manual.
SA-434