Takeuchi compact excavator TB125, TB135, TB145 / diesel TNE / diesel Yanmar. Service Manual - page 1

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TB125, 135, 145

FOREWORD

This manual is intended for persons who engage in maintenance operations, and explains
procedures for disassembly and reassembly of the machine, check and maintenance procedures,
maintenance reference values, troubleshooting and outline specifications, etc. Please use this
manual as a reference in service activities to improve maintenance techniques.
Further, please be advised that items contained in this manual are subject to change without notice
due to design modifications, etc.

MACHINE FRONT AND REAR, LEFT AND RIGHT

The end where the dozer blade is mounted is the front and the end with the travel motors is the
rear. Also the right and left sides of the operator when he is seated in the driver’s seat are the right
and left sides of the machine.

MACHINE SERIAL NUMBER

The machine serial number is stamped on the identification plate. When sending reports and
inquiries, and when ordering parts, etc., be sure to include this number.

MANUAL CONTROL

Information on those to whom this manual is distributed is recorded in the ledger in the section
in charge at this company, so please decide on a person to be in charge of it and control it. When
there are updates or additions, etc., we will notify the person in charge.

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TB125, 135, 145

1. Page number

The following page numbers are assigned to each respective page. And if there are additional pages, an addition
code is supplied. Please file the sheets in the order of the page numbers.

Page No.

X–XX

Page number within section
Section Number

Page Addition

X–XX–X

Addition Code

Example: II-8

II-9
II-9-1 ............... A page is added between page 9 and page 10.
II-10

If a page has been revised, it is to be used in place of the page used before revision and it is not necessary to keep
the old page.

2. Revision number

Indicates the revision of this manual. This number is printed on the page that reflects this revision.

3. Model (s)

SYMBOLS

 means “Please refer to the section quoted.”

 Indicates the tightening torque at the specific section that requires special attention in designing.

 Indicates the mass of a part or device.

FOOT OF THE PAGE

L4A100

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TB125, 135, 145

I .

GENERAL

II .

SPECIFICATIONS

III .

MACHINE  CONFIGURATION

IV .

  HYDRAULIC  UNITS

V .

  TROUBLESHOOTING

VI .

  ENGINE

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TB125, 135, 145

I .

  GENERAL

GENERAL

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CONTENTS

Safety Precautions ................................................................................................................................................. 3

Cautions during Disassembly and Assembly ........................................................................................................ 9

Cautions during Removal and Installation of the Hydraulic Units ..................................................................... 10

Cautions during Removal and Installation of Piping .......................................................................................... 11

Handling of Seals ................................................................................................................................................ 12

Tightening Torques ............................................................................................................................................. 13

GENERAL

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TB125, 135, 145

Observe all safety rules

• Operation, inspection and maintenance of this ma-

chine must be performed only by a trained and
qualified person.

• All rules, regulations, precautions and safety pro-

cedures must be understood and followed when
performing operation, inspection and maintenance
of this machine.

• Do not perform any operation, inspection and

maintenance of this machine when under the ad-
verse influence of alcohol, drugs, medication, fa-
tigue, or insufficient sleep.

Wear appropriate clothing and personal
protective equipment

• Do not wear loose clothing or any accessory that

can catch on controls or in moving parts.

• Do not wear oily or fuel stained clothing that can

catch fire.

SAFETY ALERT SYMBOL

This symbol means Attention! Be Alert! Your Safety Is Involved.
The message that follows the symbol contains important information about safety.
Read and understand the message to avoid personal injury or death.

■

SIGNAL WORDS

Safety messages appearing in this manual and on machine decals are identified by the words “DANGER”,
“WARNING” and “CAUTION”. These signal words mean the following:

IMPORTANT:

 The word “IMPORTANT” is used to alert against operators and maintenance personnel

about situations which can result in possible damage to the machine and its components.

This manual is intended for trained and qualified personnel only. Warnings or cautions described in this manual do
not necessarily cover all safety measures. For maintenance work, each person must take adequate safety precautions
against possible hazards present in the respective working environment.

The word “DANGER” indicates
an imminently hazardous situ-
ation which, if not avoided, can
result in serious injury or death.

DANGER

The word “WARNING” indi-
cates a potentially hazardous
situation which, if not avoided,
could result in serious injury or
death.

The word “CAUTION” indi-
cates a potentially hazardous
situation which, if not avoided,
may result in minor or moder-
ate injury.

CAUTION

WARNING

• Wear a hard hat, safety shoes, safety glasses, filter

mask, heavy gloves, ear protection and other pro-
tective equipment as required by job conditions.
Wear required appropriate equipment such as safety
glasses and filter mask when using grinders, ham-
mers or compressed air, as metal fragments or
other objects can fly and cause serious personal
injury.

• Use hearing protection when operating the ma-

chine. Loud prolonged noise can cause hearing
impairments, even the total loss of hearing.

SAFETY PRECAUTIONS

GENERAL

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TB125, 135, 145

Provide a fire extinguisher and first aid
kit

• Know where a fire extinguisher and first aid kit are

located and understand how to use them.

• Know how to contact emergency assistance and

first aid help.

Attach a “DO NOT OPERATE” tag

Severe injury could result if an unauthorized person
should start the engine or touch controls during in-
spection or maintenance.
• Stop the engine and remove the key before per-

forming maintenance.

• Attach a “DO NOT OPERATE” tag to the starter

switch or control lever.

Use the correct tools

Do not use damaged or weakened tools or tools
designed for other purposes. Use tools suited for the
operation at hand.

Replace important safety parts
periodically

• Replace fuel hoses periodically. Fuel hoses be-

come weaker over time, even if they appear to be
in good shape.

• Replace important safety parts whenever an ir-

regularity is found, even if it is before the normal
time for replacement.

Anti-explosive lighting

Use anti-explosive electrical fixtures and lights when
inspecting fuel, oil, coolant, battery fluid, etc. If
lighting that is not anti-explosive should break, the
substance could ignite, resulting in serious injury or
death.

Do not allow unauthorized personnel in
the work area

Do not allow unauthorized personnel in the work
area. Chips or other debris can fly off machine parts
when grinding, welding or using a hammer.

Prepare the work area

• Select a firm, level work area. Make sure there is

adequate light and, if indoors, ventilation.

• Clear obstacles and dangerous objects. Eliminate

slippery areas.

GENERAL

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TB125, 135, 145

Always clean the machine

• Clean the machine before performing maintenance.
• Cover electrical parts when washing the machine.

Water on electrical parts could cause short-circuits
or malfunctions.
Do not use water or steam to wash the battery,
sensors, connectors or the operator’s seat area.

Stop the engine before performing
maintenance

• Avoid lubrication or mechanical adjustments with

the machine in motion or with the engine running
while stationary.

• If maintenance must be performed with the engine

running, always work as a 2-person team with one
person sitting in the operator’s seat while the other
works on the machine.
• When performing maintenance, be sure to keep

your body and clothing away from moving
parts.

Stay clear of moving parts

• Stay clear of all rotating and moving parts. Wrap-

ping or entanglement may result in serious injury
or death.

• Keep hands, clothing and tools away from the

rotating fan and running fan belts.

Securely block the machine or any
component that may fall

• Before performing maintenance or repairs under

the machine, set all working equipment against the
ground or in the lowermost position.

• Securely block the tracks.
• If you must work beneath the raised machine or

equipment, always use wood blocks, jack-stands
or other rigid and stable supports. Never get under
the machine or working equipment if they are not
sufficiently supported. This procedure is espe-
cially important when working on hydraulic cylin-
ders.

Securely block the working equipment

To prevent unexpected movement, securely block the
working equipment when repairing or replacing the
cutting edges or bucket teeth.

Secure the engine hood or cover when
opened

Be sure to secure the engine hood or cover when
opening it. Do not open the engine hood or cover on
slopes or in strong wind.

Cautions on tilting up the platform

• Raising or lowering the platform while the engine

is running may cause the machine to move, and
cause serious injury or death.
Stop the engine before raising or lowering the
platform.

• When the floor is tilted up, support it firmly with

the stopper to prevent it from falling.

GENERAL

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TB125, 135, 145

Place heavy objects in a stable position

When removing or installing the hoe attachment,
place it in a stable position so that it does not tip over.

Use caution when fueling

• Do not smoke or permit open flames while fueling

or near fueling operations.

• Never remove the fuel cap or refuel with the engine

running or hot. Never allow fuel to spill on hot
machine components.

• Maintain control of the fuel filler nozzle when

filling the tank.

• Do not fill the fuel tank to capacity. Allow room for

expansion.

• Clean up spilled fuel immediately.
• Tighten the fuel tank cap securely. Should the fuel

cap be lost, replace it only with the original
manufacturer’s approved cap. Use of a non-ap-
proved cap without proper venting may result in
pressurization of the tank.

• Never use fuel for cleaning purposes.
• Use the correct fuel grade for the operating season.

Handling of hoses

Fuel, oil or hydraulic fluid leaks can cause a fire.
• Do not twist, bend or hit the hoses.
• Never use twisted, bent or cracked hoses, tubes and

pipes. They may burst.

• Retighten loose connections.

Be careful with hot and pressurized
components

Stop the engine and allow the machine to cool down
before performing inspection and maintenance.
• The engine, muffler, radiator, hydraulic lines, slid-

ing parts and many other parts of the machine are
hot directly after the engine is stopped. Touching
these parts will cause burns.

• The engine coolant, oil and hydraulic fluid are also

hot and under high pressure.
Be careful when loosening caps and plugs. Work-
ing on the machine under these conditions could
result in burns or injuries due to the hot oil spurting
out.

Be careful with hot cooling systems

Do not remove the radiator cap or drain plugs when
the coolant is hot. Stop the engine, let the engine and
radiator cool and loosen the radiator cap or drain plugs
slowly.

GENERAL

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TB125, 135, 145

Be careful with fluids under pressure

Pressure can be maintained in the hydraulic circuit
long after the engine has been shut down.
• Release all pressure before working on the hydrau-

lic system.

• Hydraulic fluid under pressure can penetrate the

skin or eyes and cause injury, blindness or death.
Fluid escaping from a small hole can be almost
invisible. Wear a safety goggles and heavy gloves
and use a piece of cardboard or wood to search for
suspected leaks.
If fluid is injected into the skin, it must be removed
within a few hours by a doctor familiar with this
type of injury.

Release all pressure before working on
the hydraulic system

Oil may spurt out if caps or filters are removed or
pipes disconnected before releasing the pressure in
the hydraulic system.
• Gradually loosen the vent plug to relieve tank

pressure.

• Move all the control levers and pedals several

times in all directions to release the pressure from
the working equipment circuitry. (For link type
controls)

• When removing plugs or screws or disconnecting

hoses, stand to the side and loosen slowly to gradu-
ally release the internal pressure before removing.

Be careful with grease under pressure

The track adjuster contains highly pressurized grease.
If the tension is adjusted without following the pre-
scribed procedure, the grease discharge valve may fly
off, resulting in injury.
• Loosen the grease discharge valve slowly. Do not

unfasten it more than one full turn.

• Do not put your face, arms, legs or body in front of

the grease discharge valve.

Disconnect the battery

Disconnect the battery before working on the electri-
cal system or doing any welding. Remove the nega-
tive (–) battery cable first. When reconnecting the
battery, connect the negative (–) battery cable last.

GENERAL

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TB125, 135, 145

Checks after maintenance

• Gradually raise the engine speed from a low idle to

maximum speed and check that no oil or air is
leaking from serviced parts.

• Move the controls and check that the machine is

operating properly.

Disposing of wastes

• Funnel spent fluids from the machine into contain-

ers. Disposing of fluids improperly destroys the
environment.

• Follow the prescribed regulations when disposing

of oil, fuel, engine coolant, refrigerant, solvents,
filters, batteries or other harmful substances.

Avoid battery hazards

• Batteries contain sulfuric acid which will damage

eyes or skin on contact.
• If acid contacts eyes, flush immediately with

clean water and get prompt medical attention.

• If acid is accidentally swallowed, drink large

quantities of water or milk and call a physician
immediately.

• If acid contacts skin or clothing, wash off imme-

diately with clean water.

• Wear safety glasses and gloves when working with

batteries.

• Batteries generate flammable and explosive gases.

Keep arcs, sparks, flames and lighted tobacco
away.

• Use a flashlight to check battery electrolyte level.
• Stop the engine and shut off electrical equipment

while inspecting or handling the battery.

• Do not short circuit the battery posts with metal

items.

• Always unfasten the negative (–) battery cable first

when disconnecting the battery cable. Always con-
nect the negative (–) battery cable last when fasten-
ing the battery cable.

• Loose battery terminals may result in sparks. Be

sure to fasten terminals tightly.

• Make sure the vent caps are tightened securely.
• Do not charge a battery or jump-start the engine if

the battery is frozen. Warm to 15

°

C (60

°

F) or the

battery may explode.

Have a Takeuchi service agent repair
welding cracks or other damage

Ask a Takeuchi service agent to repair any welding
problems which are detected. If not feasible, make
sure the welding is done by a qualified person in a
properly equipped workplace.

Safety signs

• Keep all safety signs clean and legible.
• Replace all missing, illegible or damaged safety

and warning signs.

GENERAL

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CAUTIONS DURING DISASSEMBLY AND
ASSEMBLY

1. Clean the machine before disassembly operation.

2. Before disassembly, check the machine condi-

tions and record them.
• Model, Machine Serial Number, Hourmeter
• Reason for Repairs, Repair History
• Dirtiness of Filters
• Fuel and Oil Conditions
• Damage to each parts, etc.

3. To make reassembly operations easy, make match-

ing marks at the necessary points.

4. Clean all disassembled parts and new parts, then

arrange them in the proper sequence.

5. Be sure to replace all seals and cotter pins, etc.,

with new parts.

6. Keep parts which should not come in contact with

oil and water separate from parts with oil on them.
• Electrical Parts, Rubber, V-Belts, etc.

7. When installing bearings, bushings and oil seals,

as a rule, use a press. When a hammer, etc., is
used, it leaves bruises.

8. Wipe all joining surfaces clean so that there is no

dirt or dust adhering to them.

9. Wrap seal tape from the front end, Wrapping it

tight and leaving 1 or 2 threads bare, Overlap the
tape by about 10 mm.

10. When fitting the snap rings, the bigger, rounder

side of their circumferences should face the mat-
ing surfaces.

SEALING TAPE

LEAVE 1 OR 2 THREAD MARGIN

GENERAL

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CAUTIONS DURING REMOVAL AND
INSTALLATION OF THE HYDRAULIC UNITS

1. Make sure that the hydraulic oil’s temperature

has dropped.

2. To prevent a loss of flow of the hydraulic oil, the

residual pressure in the piping and the internal
pressure in the hydraulic oil tank should be bled
out.

3. Be sure to install caps or plugs  on all openings in

the hydraulic unit to prevent dirt from getting into
the unit through the openings.

4. It is easy to mistake hydraulic oil adhering to the

hydraulic unit for an oil leak, so wipe the unit off
thoroughly.

5. Be sure that no damage is done to the plating on

the rod in the hydraulic cylinder.

6. As a rule, removal and installation of the hydrau-

lic cylinder should be done with the rod fully
retracted.

7. Be sure to bleed the air after replacing the hydrau-

lic oil or removing any of the hydraulic devices.

“III. Machine Configuration, Hydraulic Sys-
tem”

8. After installation of the hydraulic unit, be sure to

pressurize the hydraulic oil tank. If this operation
is forgotten, it could cause cavitation of the hy-
draulic pump. Also, it could have a drastic effect
on the life of the hydraulic pump.

“III. Machine Configuration, Hydraulic Sys-
tem”

PLUG

PLUG

GENERAL

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TB125, 135, 145

CAUTIONS DURING REMOVAL AND
INSTALLATION OF PIPING

1. When hydraulic hoses are installed, tighten them

once to the prescribed torque, then loosen them
slightly and retighten them to the prescribed
torque.
• Tighten the fittings after the installation sur-

faces fit snugly together.

• Pieces wrapped with seal tape are excluded.

2. Use 2 spanners, each on an opposite side, to

remove and tighten fittings so that the hoses or
steel pipes are not twisted.

3. After installation of hydraulic hoses or steel pipes,

apply the maximum working pressure 5 or 6 times
and confirm that there is no leakage.