Hitachi ZX 38U-5A User manual

TADC-EN-01
ZX38U-5AHYDRAULIC EXCAVATOR TECHNICAL MANUAL
Service Manual consists of the following separate Part No.
Technical Manual : Vol. No.TADC-EN
Workshop Manual : Vol. No.WADC-EN
Engine Manual : Vol. No.ETADB-EN, EWADB-EN
TADC-EN-01
PART NO.
Hydraulic Excavator
Technical Manual
38U-5A
ZX
PRINTED IN JAPAN (K) 2014, 09
URL:http://www.hitachi-c-m.com

INTRODUCTION
IN-01
To The Reader
Additional References
Manual Composition
Page Number
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
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-02
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
fNOTE: The numerical value in this manual might be
different from the above-mentioned table.
SI Units (International System of Units) are used in this
manual. MKSA system units and English units are also
indicated in parentheses just behind SI units.
Example: 24.5 MPa (250 kgf/cm2, 3560 psi)
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).
E-ECU Engine Controller Engine controller. E-ECU controls fuel injection amount
according to the machine operating condition.
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.
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.
CSD Cold Start Device Engine start device at low temperature. It increasingly
advances the fuel injection timing and increases the fuel
injection amount a little when coolant temperature is less
than 5 °C. Therefore, the engine starting is improved.

SYMBOL AND ABBREVIATION
SY-2
(Blank)

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 do not use any of the designated signal
words above after the safety alert symbol are occasionally
used on this machine.
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 an element of
information.
SAFETY
SA-688
SA-1223
SA-1

Follow Safety Instructions
Carefully read and follow all safety signs on the machine as
well as all safety messages in operator's manual.
Safety signs must be installed, maintained and replaced if
damaged.
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).
Allow only properly trained, qualified, authorized personnel
to operate the machine.
Learn how to correctly operate and service 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 part safety, function,
and/or service life. In addition, personal accident,
machine trouble, and/or damage to material caused by
unauthorized modifications will void Hitachi Warranty
Policy.
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
possible hazardous situation you may encounter. If you
have any questions concerning safety, you should first
consult your supervisor and/or your authorized dealer
before operating or performing maintenance work on the
machine.
SAFETY
SA-2
SA-003

Prepare For Emergencies
Be prepared if a fire starts or if an accident occurs.
Keep a first aid kit and fire extinguisher on hand.
Thoroughly read and understand the label attached on
the fire extinguisher and 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
any fire or accidents which may occur.
Keep emergency numbers for doctors, ambulance
service, hospitals, 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 belt
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-3
SA-437
SA-438

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
If any abnormality is found, be sure to repair it immediately
before operating the machine.
In the walk-around inspection, be sure to cover all
points described in the “Daily Inspection”section in the
operator’s manual.
SAFETY
SA-4
SA-434
SA-435

General Precautions for Cab
Always keep inside the cab clean by observing instructions
below, to prevent any personal accidents from occurring.
Before entering the cab, thoroughly remove all dirt
and/or oil such as mud, grease, soil or stones that may
mess up the cab from the soles of your work boots. If
any controls such as a pedal is operated while with dirt
and/or oil on the soles of the operator’s work boots, the
operator’s foot may slip off the pedal, possibly resulting
in a personal accident.
Do not mess up around the operator’s seat with parts,
tools, soil, stones, obstacles that may fold up or turn
over, cans or lunch box. The levers or pedals become
inoperable if obstacle jams in operation stroke of the
travel levers/pedals, pilot control shut-off lever or control
levers, which may result in serious injury or death.
Avoid storing transparent bottles in the cab. Do not
attach any transparent type window decorations on
the windowpanes as they may focus sunlight, possibly
starting a fire.
Refrain from listening to the radio, or using music
headphones or mobile telephones in the cab while
operating the machine.
Keep all flammable objects and/or explosives away from
the machine.
After using the ashtray, always cover it to extinguish the
match and/or tobacco.
Do not leave cigarette lighters in the cab. If the
temperature in the cab increases, the lighter may
explode.
Use proper floor mat dedicated to the machine. If another
floor mat is used, it may be displaced and contact with
the travel pedals during operation, resulting in serious
injury or death.
Use Handrails and Steps
Falling is one of the major causes of personal injury.
When you get on and off the machine, always use the
crawler instead of the step for safety. Also get on and off
from the position of the crawler that can secure your feet
space enough.
When you get on and off the machine, always face the
machine.
Maintain a three-point contact with the steps and
handrails.
Do not use any controls as handholds.
Never jump on or off the machine. Never mount or
dismount a moving machine.
In case adhered slippery material such as oil, grease,
or mud is present on steps, handrails, or platforms,
thoroughly remove such material.
SAFETY
SA-5
SA-439

Adjust the Operator’s Seat
A poorly adjusted seat for either the operator or the work
at hand may quickly fatigue the operator leading to mis-
operation of the machine.
The seat should be adjusted whenever the operator for
the machine changes.
The operator should be able to fully depress the pedals
and to correctly operate the control levers with his back
firmly against the seat back.
If not, readjust the seat forward or backward, and check
again.
Ensure Safety Before Rising From or Leaving
Operator’s Seat
Before rising from the operator’s seat to open/close cab
front window or to adjust the seat position, be sure to first
lower the front attachment to the ground and then move
the pilot control shut-off lever to the LOCK position. Failure
to do so may allow the machine to unexpectedly move
when a body part unintentionally comes in contact with a
control lever, possibly resulting in serious personal injury or
death.
Before leaving the machine, be sure to first lower the front
attachment to the ground and then move the pilot control
shut-off lever to the LOCK position. Turn the key switch OFF
to stop the engine.
Before leaving the machine, close all windows, doors, and
access covers and lock them up.
SAFETY
SA-6
SA-378

Fasten Your Seat Belt
If the machine should overturn, the operator may become
injured and/or thrown from the cab. Additionally the
operator may be crushed by the overturning machine,
resulting in serious injury or death.
Be sure to remain seated with the seat belt securely
fastened whenever operating the machine.
Prior to operating the machine, thoroughly examine
webbing, buckle and attaching hardware. If any item is
damaged or worn, replace the seat belt or component
before operating the machine. Replace the seat belt at
least once every 3 years regardless of appearance.
Move and Operate Machine Safely
Always be aware that there is a potential danger around the
machine while operating the machine.
Take extra care not to run over bystanders. Confirm the
location of bystanders before moving, swinging, or
operating the machine.
Always keep the travel alarm and horn in working
condition (if equipped).
Before starting to move or operate the machine, sound
the travel alarm and horn to alert bystanders.
Use a signal person when moving, swinging, or operating
the machine in congested areas. Locate the signal person
so that the operator can always witness the signal person.
Coordinate the meanings of all safety signs, hand signals
and marks before starting the machine. Appoint a person
who is responsible to make a signal and/or guidance.
Never allow any persons or obstacles to enter the
machine operation areas.
Use appropriate illumination.
SAFETY
SA-7
SA-237
SA-1291

Operate Only From Operator’s Seat
Inappropriate engine starting procedures may cause the
machine to runaway, possibly resulting in serious injury or
death.
Start the engine only when seated in the operator’s seat.
NEVER start the engine while standing on the tracks or on
ground.
Do not start engine by shorting across starter terminals.
A hazardous situation may be created and/or possible
damage to the machine may result.
Before starting the engine, confirm that all control levers
are in neutral.
Jump Starting
Failure to follow correct jump starting procedures could
result in a battery explosion or a runaway machine.
If the engine must be jump started, be sure to follow the
instructions shown in the “OPERATING ENGINE”chapter.
The operator must be seated in the operator’s seat so
that the machine will be under control when the engine
starts. Jump starting is a two-person operation.
Never use a frozen battery.
Failure to follow correct jump starting procedures could
result in a battery explosion or a runaway machine.
Keep Riders Off Machine
Riders on machine are subject to injury such as being struck
by foreign objects and being thrown off the machine.
Riders also obstruct the operator’s view, resulting in the
machine being operated in an unsafe manner.
Only the operator is allowed on the machine. Keep riders
off.
SAFETY
SA-8
SA-444
SA-032
SA-1292

Precautions for Operations
Thoroughly make certain safety at the work site before
starting operations. Especially always observe the following
points.
Be sure to wear close fitting clothing and required safety
items, such as a hard hat, when operating the machine.
Keep all bystanders and unnecessary objects out of and
away from the machine working areas. Always beware of
the surroundings while operating the machine. Take care
not to allow the rear part of the upperstructure to come
in contact with objects when swinging the machine in a
small area.
When loading a dump truck, bring the bucket from the
rear side of the dump truck to avoid moving the bucket
over the dump truck cab or over any co-workers.
SAFETY
SA-9
M586-12-012

Investigate Job Site Beforehand
When working at the edge of an excavation or on a road
shoulder, the machine could tip over due to collapse of the
ground, possibly resulting in serious injury or death.
Investigate the configuration and ground conditions of
the job site beforehand to prevent the machine from
falling and to prevent the ground, stockpiles, or banks
from collapsing.
Make a work plan. Use machines appropriate to the work
and job site.
Reinforce ground, edges, and road shoulders as
necessary. Keep the machine well back from the edges of
excavations and road shoulders.
When working on an incline or on a road shoulder,
employ a signal person as required.
Never allow bystanders to enter the working area such as
swing radius or traveling range.
When the footing is weak, reinforce the ground before
starting work.
When working on frozen ground, be extremely alert. As
ambient temperatures rise, footing may become loose
and slippery.
When operating the machine near open flame, sparks,
and/or dead grass, a fire may easily break out. Use special
care not to cause a fire.
Make sure the work site ground has sufficient strength
to firmly support the machine. When working close to an
excavation or on road shoulders, operate the machine with
the tracks positioned perpendicular to the cliff face with
travel motors at the rear and with the blade at the front, so
that the machine can more easily evacuate if the cliff face
collapses.
If working at the bottom of a cliff or on a high bank is
required, be sure to investigate the area first and confirm
that no danger of the cliff or bank collapsing exists. If any
possibility of cliff or bank collapsing exists, do not work in
that area.
Soft ground may collapse when operating the machine on
it, possibly causing the machine to tip over. When working
on a soft ground is required, be sure to reinforce the ground
first using large pieces of steel plates strong enough and
firm to easily support the machine.
Note that there is always a possibility of machine tipping
over when working on rough terrain or on slopes. Prevent
machine tipping over from occurring. Operate the machine
slowly to ensure safe operation.
SAFETY
SA-10
SA-1293
M586-05-021

Equipment of OPG
In case the machine is operated in areas where the
possibility of falling stones or debris exists, equip genuine
Hitachi OPG guard. Contact your nearest Hitachi dealer for
installation method of the OPG guard. Depending on the
specifications applied to your machine, modification of the
machine to meet ROPS standards will be possible.
To maintain unimpaired operator protection and
manufacture’s protective structure.
Damaged ROPS, OPG guard must be replaced, not
repaired or revised.
Any alternation to the ROPS or OPG guard must be
approved by the manufacturer.
ROPS : Roll Over Protective Structure
OPG : Operator Protective Guard
Provide Signals for Jobs Involving Multiple
Machines
In case more than one machine is operated in the same
job site, accidental collision between machines may cause
serious injury or death.
For jobs involving multiple machines, provide signals
commonly known by all personnel involved. Also, appoint
a signal person to coordinate the job site. Make sure that all
personnel obey the signal person’s directions.
Confirm Direction of Machine to be Driven
Incorrect travel pedal/lever operation may result in serious
injury or death.
Before driving the machine, confirm the position of the
undercarriage in relation to the operator’s position.
If the travel motors are located towards the front of the
cab, the machine will move in the reverse direction when
travel pedals/levers are operated.
SAFETY
SA-11
SA-490
SA-481
SA-1294

Drive Machine Safely
Use a signal person when traveling the machine along road
shoulders or in congested areas.
Driving the machine in the incorrect direction may result in
serious injury or death and/or severe damage to property.
Before driving the machine, always confirm that the travel
pedals/levers direction corresponds to the direction you
wish to drive.
Be sure to detour around any obstructions.
Avoid traveling over obstructions. Soil, fragments of rocks,
and/or metal pieces may scatter around the machine. Do
not allow personnel to stay around the machine while
traveling.
Driving on a slope may cause the machine to slip or
overturn, possibly resulting in serious injury or death.
Never attempt to ascend or descend 30 degrees or
steeper slopes.
Be sure to fasten the seat belt.
When driving up or down a slope, keep the bucket facing
the direction of travel, approximately 200 to 300 mm (8 to
12 in) (A) above the ground.
If machine starts to skid or becomes unstable,
immediately lower the bucket to the ground and stop.
Driving across the face of a slope or steering on a
slope may cause the machine to skid or turnover. If
the direction must be changed, move the machine to
level ground, then, change the direction to ensure safe
operation.
Avoid swinging the upperstructure on slopes. Never
attempt to swing the upperstructure downhill. The
machine may tip over. If swinging uphill is unavoidable,
carefully operate the upperstructure and boom at slow
speed.
If the engine stalls on a slope, immediately lower the
bucket to the ground. Return the control levers to neutral.
Then, restart the engine.
Be sure to thoroughly warm up the machine before
ascending steep slopes. If hydraulic oil has not warmed
up sufficiently, sufficient performance may not be
obtained.
SAFETY
SA-12
A
A
WRONG
SA-441
SA-1296
SA-1295
SA-589

When the machine descends a slope at high speed,
machine weight accelerates descending speed. It may
cause collision accident due to misjudging of braking
distance or machine turnover due to running on an
unexpected obstacle.
Always ensure that travel mode display (1) on the monitor
is , and then reduce the engine speed before
descending a slope.
Select a travel route that is as flat as possible. Steer the
machine as straight as possible, making small gradual
changes repeatedly in direction.
Check the strengths of bridges and road shoulders before
traveling on them, and reinforce if necessary.
When the machine is equipped with steel shoes, cover
the road surface with wood plates in order not to damage
the road surface. Be careful of steering when operating
on asphalt roads in summer.
When crossing train tracks, lay wood plates over the
tracks not to allow the machine to ride on only the rails.
Check that the machine can pass under a bridge and
electric lines before driving the machine.
When crossing a river, drive the machine slowly while
measuring the depth of the river using the bucket. Do not
cross the river when the depth of the river is deeper than
the upper track shoe surface.
Reduce the engine speed when traveling on rough
terrains. Select a slow travel speed. Slower speed will
reduce possible damage to the machine.
Drive the machine so that the travel motors do not come
in contact with loose rocks. If the machine crosses over
an obstruction, abnormally large loads may be loaded
on the machine. Avoid contact with an obstruction while
traveling the machine.
During freezing weather, always clean snow and ice from
track shoes before driving the machine on snowy and/or
frozen roads, or loading and unloading the machine for
transportation, to prevent the machine from slipping.
SAFETY
SA-13
Travel Motor
MADB-00-007
M104-05-008
SA-673
M586-05-002
1

Avoid Injury From Rollaway Accidents
Death or serious injury may result if you attempt to mount
or try to bodily stop a moving machine.
Park the machine in compliance with the safe parking
procedures described in operator's manual to prevent the
machine from running away.
Block both tracks and lower the bucket to the ground,
thrust the bucket teeth into the ground if you must park
on a grade.
Park at a reasonable distance from other machines.
SAFETY
SA-14
SA-1297