Kubota Z122E, Z121S, Z125E, Z125S Operators Manual

OPERATOR'S MANUAL

MODELS Z122E
Z121S
Z125E

AS . E . 2 - 2 . - . AK

English
Code No. K3011-7123-2

Z125S

Z
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1BDABDYAP0010

PRINTED IN U.S.A.

KUBOTA Corporation 2013

©

READ AND SAVE THIS MANUAL

ABBREVIATION LIST

Abbreviations Definitions

API

PTO

RH/LH

ROPS

rpm

SAE

American Petroleum Institute

Power Take Off

Right-hand and left-hand sides are determined by facing in
the direction of forward travel

Roll-Over Protective Structures

Revolutions Per Minute

Society of Automotive Engineers

UNIVERSAL SYMBOLS

As a guide to the operation of your machine, various universal symbols have been utilized on the instruments and
controls. The symbols are shown below with an indication of their meaning.

Safety Alert Symbol

Read Operator's Manual

Gasoline Fuel

Fuel-Level

Power Take-Off Switch Control-Off Position
(Disengaged)

Power Take-Off Switch Control-On Position
(Engaged)

Hours

KUBOTA Corporation is ···

Since its inception in 1890, KUBOTA Corporation has grown to
rank as one of the major firms in Japan.

To achieve this status, the company has through the years
diversified the range of its products and services to a remarkable
extent, until today, 19 plants and 16,000 employees produce over
1,000 different items, large and small.

All these products and all the services which accompany them,
however, are unified by one central commitment. KUBOTA makes
products which, taken on a national scale, are basic necessities.
Products which are indispensable, products intended to help
individuals and nations fulfill the potential inherent in their
environment. For KUBOTA is the Basic Necessities Giant.

This potential includes water supply, food from the soil and from
the sea, industrial development, architecture and construction,
transportation.

Parking Brake-Engaged position

Parking Brake-Disengaged position

Engine-Stop

Engine-Run

Starter Control

California Proposition 65

WARNING

Engine exhaust, some of its constituents,
certain vehicle components and fluids,
contain or emit chemicals known to the
State of California to cause cancer and birth
defects or other reproductive harm.

This spark ignition system complies with Canadian ICES-002.

Cutting Height

Fast

Slow

Engine Speed Control

Choke

Thousands of people depend on KUBOTA's know-how, technology,
experience and customer service. You too can depend on
KUBOTA.

FOREWORD

You are now the proud owner of a KUBOTA ZERO TURN MOWER. This machine
is a product of KUBOTA's quality engineering and manufacturing. It is made of
excellent materials and under a rigid quality control system. It will give you long,
satisfactory service. To obtain the best use of your machine, please read this
manual carefully. It will help you become familiar with the operation of the machine
and contains many helpful hints about machine maintenance. It is KUBOTA's policy
to utilize, as quickly as possible, every advance in our research. The immediate use
of new techniques in the manufacturing of products may cause some small parts of
this manual to become outdated. KUBOTA distributors and dealers will have the
most up-to-date information. Please do not hesitate to consult them.

3

This symbol, the industry's ''Safety Alert Symbol'', is used throughout this manual
and on labels on the machine itself to warn of the possibility of personal injury.
Read these instructions carefully. It is essential that you read the instructions and
safety regulations before you attempt to assemble or use this unit.

3
3
3

IMPORTANT :

NOTE :

DANGER :

WARNING :

CAUTION :

Indicates an imminently hazardous situation which, if not
avoided, will result in death or serious injury.

Indicates a potentially hazardous situation which, if not
avoided, could result in death or serious injury.

Indicates a potentially hazardous situation which, if not
avoided, could result in minor or moderate injury.

Indicates that equipment or property damage could result if
instructions are not followed.

Gives helpful information.

SAFETY FIRST

CONTENTS

SAFE OPERATION ............................................................................................ -1

SERVICING OF MACHINE ......................................................................................... 1

SPECIFICATIONS....................................................................................................... 3

IMPLEMENT LIMITATIONS ........................................................................................ 5

INSTRUMENT PANEL AND CONTROLS................................................................... 6

MOWER MOUNTING .................................................................................................. 8

MOUNTING THE MOWER DECK ........................................................................... 8

ADJUSTING THE MOWER ..................................................................................... 8

DISMOUNTING THE MOWER DECK ..................................................................... 8

OPERATING THE ENGINE......................................................................................... 9

MOUNT AND DISMOUNT MACHINE SAFELY....................................................... 9

STARTING THE ENGINE ........................................................................................ 9

Throttle Lever..................................................................................................................11

Key Switch......................................................................................................................11

CHECK DURING OPERATING ............................................................................. 12

Immediately Stop the Engine if:......................................................................................12

Fuel Gauge.....................................................................................................................12

Hour Meter......................................................................................................................12

COLD WEATHER STARTING ............................................................................... 12

WARMING UP ....................................................................................................... 13

Warm-up and Transmission Oil in the Low Temperature Range....................................13

JUMP STARTING .................................................................................................. 13

STOPPING THE ENGINE...................................................................................... 14

OPERATING THE MACHINE.................................................................................... 15

OPERATING NEW MACHINE ............................................................................... 15

Changing Lubricating Oil for New Machines...................................................................15

Engine Break-in ..............................................................................................................15

Machine Break-in............................................................................................................ 15

STARTING ............................................................................................................. 16

Operator's Seat...............................................................................................................16

Seat Belt .........................................................................................................................16

Light Switch ....................................................................................................................16

Mower Lift Pedal.............................................................................................................17

Throttle Lever..................................................................................................................17

Parking Brake Lever ....................................................................................................... 17

Motion Control Lever ......................................................................................................18

STOPPING............................................................................................................. 20

PARKING ............................................................................................................... 20

TRANSPORTING................................................................................................... 21

Hydrostatic Transaxle Bypass Rods............................................................................... 21

OPERATING THE MOWER ...................................................................................... 22

MAKING THE MOST OF YOUR MOWER............................................................. 22

CONTENTS

ADJUSTING CUTTING HEIGHT ........................................................................... 22

OPERATING MOWER........................................................................................... 23

PTO Switch.....................................................................................................................23

Starting ........................................................................................................................... 24

TIRES AND WHEELS ............................................................................................... 25

TIRES..................................................................................................................... 25

Inflation Pressure............................................................................................................25

WHEELS ................................................................................................................ 25

Remove and Install Front Caster Wheels.......................................................................26

MAINTENANCE......................................................................................................... 27

SERVICE INTERVALS .......................................................................................... 27

LUBRICANTS AND FUEL...................................................................................... 30

PERIODIC SERVICE................................................................................................. 31

HOW TO RAISE THE OPERATOR'S SEAT.......................................................... 31

DAILY CHECK ....................................................................................................... 32

Checking Engine Oil Level..............................................................................................32

Checking Amount of Fuel and Refueling ........................................................................33

Checking and Cleaning Air Intake Screen......................................................................34

Checking Tire Pressure ..................................................................................................34

Inflation Pressure............................................................................................................34

Checking Transaxle Fluid Level......................................................................................35

Checking Movable Parts................................................................................................. 35

EVERY 25 HOURS ................................................................................................ 36

Cleaning Precleaner Element (Except Z125E)............................................................... 36

Cleaning Air Cleaner Element (Z122E, Z125E).............................................................. 37

EVERY 50 HOURS ................................................................................................ 39

Checking Engine Start System.......................................................................................39

Checking OPC System ...................................................................................................40

Checking Carbon Canister Air Filter ............................................................................... 40

Changing Engine Oil (Z122E, Z125E) ............................................................................41

Replacing Engine Oil Filter (Z122E, Z125E)...................................................................42

Checking Muffler and Spark Arrester (if equipped).........................................................43

EVERY 100 HOURS .............................................................................................. 43

Changing Engine Oil (Z121S, Z125S) ............................................................................43

Replacing Precleaner Element (Except Z125E) .............................................................44

Replacing Air Cleaner Element (Z122E, Z125E)............................................................44

Replacing Air Cleaner Element (Z121S, Z125S)............................................................44

Cleaning Engine Shroud................................................................................................. 45

Checking Spark Plug ...................................................................................................... 46

Checking Fuel Lines ....................................................................................................... 47

Battery Condition ............................................................................................................48

Adjusting Throttle Cable .................................................................................................50

Replacing Engine Oil Filter (Z121S, Z125S)...................................................................51

EVERY 200 HOURS .............................................................................................. 52

Checking Hydraulic Hose ...............................................................................................52

EVERY 400 HOURS .............................................................................................. 53

Replacing Transaxle Oil Filter Cartridge......................................................................... 53

Changing Transaxle Fluid............................................................................................... 54

EVERY 500 HOURS .............................................................................................. 54

CONTENTS

Electric Clutch Adjustment..............................................................................................54

Checking Engine Valve Clearance (Z121S, Z125S).......................................................55

EVERY AFTER 500 HOURS ................................................................................. 55

Cleaning Combustion Chamber......................................................................................55

EVERY 1 YEAR ..................................................................................................... 55

Replacing Precleaner Element (Except Z125E) .............................................................55

Replacing Air Cleaner Element (Z122E, Z125E)............................................................55

Replacing Air Cleaner Element (Z121S, Z125S)............................................................55

Changing Engine Oil (Z122E, Z125E) ............................................................................55

Replacing Engine Oil Filter (Z122E, Z125E)...................................................................55

Replacing Fuel Filter (Z122E, Z125E) ............................................................................55

Checking Muffler and Spark Arrester (if equipped).........................................................55

Replacing Spark Plug .....................................................................................................55

Checking Engine Valve Clearance (Z122E, Z125E).......................................................55

EVERY 2 YEARS................................................................................................... 56

Replacing Hydraulic Hose ..............................................................................................56

Replacing Fuel Lines ......................................................................................................56

Replacing Engine Breather Hose ...................................................................................56

Replacing Carbon Canister Air Filter ..............................................................................56

SERVICE AS REQUIRED...................................................................................... 56

Replacing Fuses.............................................................................................................56

Checking and Replacing Blade.......................................................................................57

Mower Belt Replacement................................................................................................58

ADJUSTMENT........................................................................................................... 59

MOTION CONTROL LEVER ................................................................................. 59

HST NEUTRAL............................................................................................................... 59

MAXIMUM SPEED (FORWARD) ...................................................................................60

MOTION CONTROL LEVER ALIGNMENT .................................................................... 60

MOWER DECK LEVEL.......................................................................................... 61

ANTI-SCALP ROLLERS................................................................................................. 61

LEVEL MOWER DECK (Side-to-Side) ...........................................................................62

LEVEL MOWER DECK (Front-to-Rear) .........................................................................63

GENERAL TORQUE SPECIFICATION ................................................................. 64

TIGHTENING TORQUE CHART ........................................................................... 65

STORAGE ................................................................................................................. 66

TROUBLESHOOTING............................................................................................... 67

ENGINE TROUBLESHOOTING ............................................................................ 67

BATTERY TROUBLESHOOTING ......................................................................... 69

MACHINE TROUBLESHOOTING ......................................................................... 69

MOWER TROUBLESHOOTING............................................................................ 70

INDEX........................................................................................................................ 72

SAFE OPERATION

Careful operation is your best insurance against an
accident. Read and understand this manual carefully
before operating the machine. All operators, no matter
how much experience they may have had, should read
this and other related manuals before operating the
machine or any implement attached to it. It is the owner's
obligation to instruct all operators in safe operation.
This mowing machine is capable of amputating hands and
feet and throwing objects. Failure to observe the following
safety instructions could result in serious injury or death.

1. BEFORE OPERATING

-1SAFE OPERATION

1. The ZERO TURN MOWING MACHINE has different
steering characteristics than other machines with a
steering wheel and does not have a service brake
pedal (but, has a parking brake lever. Normal slowing
down and stopping is done with the motion control
levers.). Read and understand the operators manual
before operating the machine. Practice operating
machine at low engine speed without mower engaged
in an unobstructed area.

2. Know your equipment and its limitations. Read all
instructions in this manual and machine safety labels
before attempting to start and operate the machine.

3. Pay special attention to the safety labels on the
machine itself.

4. KUBOTA recommends the use of a Roll Over
Protective Structures (ROPS) and seat belt in almost
all applications. This combination will reduce the risk
of serious injury or death, should the machine be
upset.
If the ROPS is loosened or removed for any reason,
make sure that all parts are reinstalled correctly before
operating the machine.
Never modify or repair a ROPS because welding,
bending, drilling, grinding, or cutting may weaken the
structure.
If any structural member of the ROPS is damaged,
replace the entire structure at your local KUBOTA
Dealer.

(1) ROPS
(2) Seat belt

5. Always use the seat belt if the machine has the ROPS.
Check the seat belt regularly and replace if frayed or
damaged.

6. Do not allow any bystanders around or near machine
during operation.

7. Do not allow passengers, children or non-qualified
operators on the machine at any time. The operator
must remain in the machine seat throughout
operation.

8. Do not operate the machine or any attachments while
under the influence of alcohol, medication, controlled
substances or when fatigued.

9. Do not wear loose, torn, or bulky clothing around
machine. The clothing may catch on moving parts or
controls, leading to the risk of accident. Wear and use
any additional safety items such as hard hat, safety
boots or shoes, eye and hearing protection, gloves,
etc. as appropriate or required.

10.Do not wear radio or music headphones while
operating the machine.
Safe operation requires your full attention.

11.Carefully check the vicinity before operating machine
or any implement attached to it. Clear the work area of
objects (wires, rocks, etc.) that might be picked up and
thrown. Check for overhead clearance which may
interfere with a grass catcher or ROPS.

12.Check brakes and other mechanical parts for correct
adjustment and wear. Replace worn or damaged parts
promptly. Check the tightness of all nuts and bolts
regularly. (For further details, see "PERIODIC
SERVICE" and "ADJUSTMENT" section.)

13.Keep all shields and guards in place. Replace any that
are damaged or missing.

14.Before allowing other people to use your machine,
explain how to operate and have them read this
manual before operation.

SAFE OPERATION-2

15.In addition to the design and configuration of
equipment, hazard control and accident prevention
are dependent upon the awareness, concern and
prudence of personnel involved in the operation,
transport and maintenance of the equipment.

16.Keep the machine and attachments in good operating
condition and keep safety devices in place and in
proper working condition.

17.Do not modify the machine. Unauthorized modification
may affect the function of the machine, which may
result in personal injury.

18.Use only implements approved by KUBOTA. Use
proper ballast to front or rear of machine to reduce the
risk of upsets. Follow the "Safe Operation"
procedures, specified in the manuals with equipment.

19.Keep your machine clean. Accumulations of dirt,
grease, and trash can contribute to fires and lead to
personal injury.

20.The exhaust gas from the muffler is very hot. To
prevent fire, do not expose dry grass, mowed grass, oil
and any other combustible materials to exhaust gas.
Use a spark arrester where required. Also keep the
engine and muffler clean all the time.

2. OPERATING

C Starting

1. Always sit in the operator's seat when starting engine
or operating levers or controls.

2. Before starting the engine make sure that the motion
control levers are in neutral lock, the parking brake is
applied, and Power Take Off (PTO) is disengaged
(OFF).

3. Do not start engine by shorting across starter
terminals. The machine may start in gear and move if
normal starting circuitry is bypassed.

4. Do not operate or idle engine in a non-ventilated area.
Carbon monoxide gas is colorless, odorless, and
deadly.

5. Do not start engine while tilting deck.

6. Check before each use that operator presence
controls are functioning correctly. Test safety systems.
(See "Checking Engine Start System" and "Checking
OPC System" in "EVERY 50 HOURS" in "PERIODIC
SERVICE" section.)
Do not operate unless they are functioning correctly.

C Working

1. Do not turn sharply when driving at high speed.

2. To avoid tip over, slow down when turning on uneven
terrain or before stopping.

3. Do not operate near ditches, holes, embankments, or
other terrain, which may collapse under the machine
weight. The risk of machine tip over increases when
the ground is loose or wet.

4. Park the machine on a firm and level surface.

5. Watch where you are going at all times. Watch for and
avoid obstacles. Be alert at curbs, near trees, and
other obstructions and hidden hazards.

6. Know what is behind you before backing up. Look to
the rear before and when backing. Do not mow while
in reverse unless absolutely necessary and make sure
the area immediately behind you is clear of
obstructions or holes and small children. Use extra
caution when machine is equipped with Grass
Catcher. Your view to the rear is restricted.

7. When working in groups, always let others know what
you are doing ahead of time.

8. Do not drive machine on streets or highways. Watch
for traffic when you cross roads or operate near roads.

9. Be aware of the mower discharge direction and do not
point it at anyone.

10.When using any attachments, never direct discharge
material toward bystanders. Do not allow anyone near
the attachments while in operation.
Do not mow when bystanders are present in the
mowing area.

11.To reduce fire hazards, keep the engine exhaust area
free of grass or leaves.

12.Be sure rotating blades and engine are stopped and
the key is removed before placing hands or feet near
blades and cleaning blockages or unclogging chute.

13.Shut the engine off and wait for all movement to stop
before removing grass catcher or unclogging chute.

14.Maintain all screens to avoid overheating conditions.

15.Always inspect the mower for damage after striking a
foreign object. Repair or replace any damaged parts
before restarting.

16.Operate during daylight or in bright artificial light.

C Children

Tragic accidents can occur if the operator is not alert to
the presence of children. Children are attracted to the
machine and mowing activity.
Never assume that children will remain where you last
saw them.

1. Keep children out of the mowing area and under the
watchful care of another responsible adult.

2. Be alert and turn machine off if children enter the area.

3. Before and when backing, look behind and down for
small children.

4. Never carry children. There is no safe place for them
to ride. They may fall off and be seriously injured or
interfere with safe machine operation.

5. Never allow children to operate the machine, even
under adult supervision.

6. Use extra care when approaching blind corners,
shrubs, trees, or other obstructions that might hide
children from sight.

7. Do not mow in reverse unless it is absolutely
necessary and make sure area to the rear is clear of
children before doing so.

-3SAFE OPERATION

C Operators, age 60 years and above

Data indicates that operators, age 60 years and above,
are involved in a large percentage of machine-related
injuries. These operators should evaluate their ability to
operate the machine safely enough to protect themselves
and others from serious injury.

C Operation on slopes

Slopes are a major factor related to loss-of-control and tip­over accidents, which can result in severe injury or death.
All slopes require extra caution.
If you cannot back up the slope or if you feel uneasy on it,
do not mow it.
If the engine stops when operating on a slope apply the
parking brake immediately to prevent machine run away.

DO

1. To avoid tip over, operate across the slopes not up and
down. Stay off hills and slopes too steep for safe
operation.

2. Remove obstacles such as rocks, tree limbs, etc.

3. Stay alert for holes in the terrain and other hidden
hazards. Keep away from drop-offs. Uneven terrain
could overturn the machine. Tall grass can hide
obstacles.

4. Follow the manufacturer's recommendations for wheel
weight or counterweights to improve stability.

5. Keep all movement on the slopes slow and gradual.
Do not make sudden changes in speed or direction.

6. Avoid starting or stopping on a slope. If tires lose
traction, disengage PTO and proceed slowly straight
down the slope.

7. Reduce speed and exercise extreme caution on
slopes and in sharp turns to prevent tip-over or loss of
control.

8. Use special caution when changing direction on
slopes. Slow down, and use extra caution when
changing direction on a slope.

C Stopping

1. Park the machine on level ground.

2. Make sure that the machine and all attachments have
come to a complete stop before dismounting.

3. Before dismounting, apply parking brake, place the
motion control levers in their neutral lock positions,
disengage the PTO, lower all attachments to the
ground, turn off the engine, and remove the key.

4. Do not park the machine on dry grass or leaves.

3. TRANSPORTING

1. Disengage power to attachment(s) when transporting
or not in use.

2. Do not tow this machine. Use a suitable truck or trailer
when transporting on public roads.

3. Use extra care when loading or unloading the machine
into a trailer or truck.

4. This machine is not allowed to be used on public
roads.

4. SERVICING AND STORAGE

C Servicing

1. Before servicing, park the machine on a firm, level
surface and apply the parking brake. Remove the key
to prevent accidental start-up.

2. Allow the machine time to cool before touching the
engine, muffler, etc.

3. Always stop the engine before refueling. Avoid spills
and overfilling. Wipe up spilled fuel immediately.

DO NOT

1. Do not turn on slopes unless necessary. If necessary,
turn uphill slowly and gradually.

2. Do not mow near drop-offs, ditches, or embankments.
The mower could suddenly turn over if a wheel is over
the edge of cliff or ditch, or if an edge caves in.

3. Do not mow on wet grass. Reduced traction could
cause sliding and loss of control.

4. Do not try to stabilize the machine by putting your foot
on the ground.

5. Do not use grass catcher on steep slopes.

6. Do not start or stop suddenly when going uphill or
downhill. Avoid sudden start and stops on slopes.

7. Never "freewheel". Do not let the machine travel
downhill with motion control levers at neutral lock
position or in neutral.

8. Do not operate machine without the mower deck
installed.

(1) Fuel tank cap

4. Use extra care in handling gasoline fuels. They are
flammable.
(1) Use only an approved container.
(2) Do not remove fuel cap or refuel with the engine

running. Allow engine to cool before refueling. Do
not smoke while refueling or when standing near
fuel.

(3) Do not refuel the machine indoors and always

clean up spilled fuel or oil.

SAFE OPERATION-4

(4) Do not store the machine or fuel container inside

where there is an open flame, such as in a water
heater.

5. Do not smoke when working around battery or when
refueling. Keep all sparks and flames away from
battery and fuel tank.
A battery, especially when charging, will give off
hydrogen and oxygen gases, which can explode and
cause serious personal injury.

6. Before "jump starting" a dead battery, read and follow
all the instructions.

7. Disconnect the battery's ground cable before working
on or near electric components.

8. Do not use or charge the refillable type battery if the
fluid level is below the LOWER (lower limit level) mark.
Otherwise, the battery component parts may
prematurely deteriorate, which may shorten the
battery's service life or cause an explosion. Check the
fluid level regularly and add distilled water as required
so that the fluid level is between the UPPER and
LOWER levels.

9. Keep first aid kit and fire extinguisher handy at all
times.

10.Do not attempt to mount a tire on a rim unless qualified
to do so and all proper safety precautions are followed.

11.Always maintain the correct tire inflation pressure. Do
not inflate tires above the recommended pressure
shown in the Operator's Manual.

20.Never tamper with safety devices. Check their
operation for proper function regularly.

21.Waste products such as used oil, fuel, coolant, brake
fluid, and batteries, can harm the environment, people,
pets and wildlife. Please dispose of properly.

22.Do not use beverage containers for waste fluids or
other products. Someone, particularly children, may
drink them by mistake.

23.Securely support machine or any machine elements
with stands or suitable blocking before working
underneath. For your safety do not rely on
hydraulically supported devices, they may leak down,
suddenly drop or be accidently lowered.

24.See your local Recycling Center or KUBOTA Dealer to
learn how to recycle or get rid of waste products.
A A Material Safety Data Sheet (MSDS) provides

specific details on chemical products; physical and
health hazards, safety procedures, and emergency
response techniques. The seller of the chemical
products used with your machine is responsible for
providing the MSDS for that product upon request.

C Storage

1. Keep the machine and supply of fuel in locked storage
and remove the ignition key to prevent children or
others from playing or tampering with them.

2. To avoid sparks from an accidental short circuit,
always disconnect the battery's ground cable (-) first
and reconnect it last.

12.Provide adequate support when changing wheels.

13.Make sure that wheel nuts and bolts have been
tightened to the specified torque.

14.Do not make adjustments or repairs with the engine
running.

15.Keep machine free of grass, leaves, or other debris
build-up.

16.Do not change the engine governor setting or
overspeed the engine.

17.Do not run a machine inside a closed area.

18.Mower blades are sharp and can cut your hands. Wrap
the blade(s) or wear gloves, and use extra caution
when servicing them.

19.Keep nuts and bolts, especially blade attachment
bolts, tight and keep equipment in good condition.

(1) Battery
(2) Ground cable

(+): Positive terminal
(-): Negative terminal

3. To avoid the danger of exhaust fume poisoning, do not
operate the engine in a closed building without
adequate ventilation.

4. To reduce fire hazards, clean the machine thoroughly
before storage. Dry grass and leaves around the
engine and muffler may ignite.

5. DANGER, WARNING AND CAUTION LABELS

-5SAFE OPERATION

SAFE OPERATION-6

-7SAFE OPERATION

SAFE OPERATION-8

6. CARE OF DANGER, WARNING, AND CAUTION LABELS

1. Keep danger, warning and caution labels clean and free from obstructing material.

2. Clean danger, warning and caution labels with soap and water, and dry with a soft cloth.

3. Replace damaged or missing danger, warning and caution labels with new labels from your local KUBOTA Dealer.

4. If a component with danger, warning and caution label(s) affixed is replaced with new part, make sure new label(s) is
(are) attached in the same location(s) as the replaced component.

5. Mount new danger, warning and caution labels by applying on a clean dry surface and pressing any bubbles to outside
edge.

SERVICING OF MACHINE

After reading this manual thoroughly, you will find that you
can do some of the regular maintenance yourself. Your
dealer is interested in helping you get the best
performance from your new machine and wants to help
you get the most value from it. When in need of parts or
major service, be sure to see your KUBOTA Dealer. When
in need of parts, be prepared to give your dealer the serial
number of the machine, ROPS, engine and mower.

Locate the serial numbers now and record them in the
space provided.

Type Serial No.

1SERVICING OF MACHINE

Machine

ROPS

Engine

Mower

Date of Purchase

Name of Dealer

(To be filled in by purchaser)

C Warranty

This machine is warranted under the Kubota Limited
Express warranty, a copy of which may be obtained from
your selling dealer. No warranty shall, however, apply if
the machine has not been handled according to the
instruction given in the Operator's Manual even it is within
the warranty period.

C Scrapping the machine and its procedure

To put the machine out of service, correctly follow the
local rules and regulations of the country or territory where
you scrap it. If you have questions, consult your local
KUBOTA Dealer.

(1) Machine identification plate
(2) Machine serial No.

[Z122E]

(1) Engine serial No.

[Z125E]

(1) Engine serial No.

SERVICING OF MACHINE2

[Z121S, Z125S]

(1) Engine serial No.

(1) Mower identification plate
(2) Mower serial No.

(1) ROPS serial No.

SPECIFICATIONS

Model Z122E Z121S Z125E Z125S

Model GH731V-1 GH736V GH733V-1 GH750V

Max. engine power
(Gross)

Type Air-cooled gasoline engine

Number of cylinders 2 (V-Twin)

Bore and stroke mm (in.)

Engine

Capacities

Dimensions

Weight (W/MOWER DECK) kg (lbs.) 330 (728) with 48" 340 (750) with 48" 340 (750) with 54" 350 (772) with 54"

Traveling
system

Total displacement cm (cu. in.) 724 (44) 725 (44) 724 (44) 747 (46)

Rated revolution rpm 3600

Fuel Unleaded gasoline

Starter Electric

Lubrication Full pressure lubrication

Cooling Air cooled

Battery U1 (12 V, RC: 45 min, CCA: 300, CA: 410)

Fuel tank L (U.S.gals.) 16 (4.2)

Engine crankcase
(with filter)

Transmission case
including Rear axle gear
case

Overall length mm (in.) 1940 (76.4)

Overall width
w/o mower deck

Overall
height

Wheelbase mm (in.) 1155 (45.5)

Min. ground clearance mm (in.)

Tread

Tires

Traveling
speeds

Steering 2 - Hand levers

Transmission 2 - HST w / Gear

Parking brake Hand lever applied, released

Min. turning radius mm (in.) 0 (0)

With ROPS mm (in.) 1652 (65.0)

Front mm (in.) 796 (31.3)

Rear mm (in.) 954 (37.6)

Front 11 x 4 - 5 (4PR) Smooth

Rear 22 x 10 - 14 (4PR) Turf

Forward mph (km/h) 0 to 8.0 (0 to 12.9)

Reverse mph (km/h) 0 to 4.0 (0 to 6.4)

kW (HP) 16.4 (22) *1*2 15.7 (21) *1*3 18.6 (25) *1*2 18.6 (25) *1*3

79 x 73

(3.11 x 2.87)

L (U.S.qts.) 1.8 (1.9)

L (U.S.qts.) 4.8 (5.1) (*4)

mm (in.) 1207 (47.5)

123 (4.84)

W/48"

83 x 67

(3.27 x 2.64)

79 x 73

(3.11 x 2.87)

83 x 69

(3.27 x 2.72)

123 (4.84)

W/54"

3SPECIFICATIONS

4 SPECIFICATIONS

Model Z122E Z121S Z125E Z125S

PTO

(Specifications and design subject to change without notice)

NOTE:

*1: Manufacturer's estimate
*2: The gross power rating for individual gas engine models is labeled in accordance with SAE (Society of
Automotive Engineers) code J1940 (Small Engine Power & Torque Rating Procedure), and rating performance has
been obtained and corrected in accordance with SAE J1995 (Revision 2002-05). Torque values are derived at 3060
RPM; horsepower values are derived at 3600 RPM. Actual gross engine power will be lower and is affected by,
among other things, ambient operating conditions and engine-to-engine variability. Given both the wide array of
products on which engines are placed and the variety of environmental issues applicable to operating the equipment,
the gas engine will not develop the rated gross power when used in a given piece of power equipment (actual "on­ site" or net power). This difference is due to a variety of factors including, but not limited to, accessories (air cleaner,
exhaust, charging, cooling, carburetor, fuel pump, etc.), application limitations, ambient operating conditions
(temperature, humidity, altitude), and engine-to-engine variability. Due to manufacturing and capacity limitations,
Briggs & Stratton may substitute an engine of higher rated power for this Series engine.
*3: Horsepower ratings exceed Society of Automotive Engineers Small Engine Test Code J1940. Actual engine
horsepower is lower and affected by, but not limited to, accessories (air cleaner, exhaust, charging, cooling, fuel
pump, etc.), application, engine speed and ambient operating conditions (temperature, humidity, and altitude).
Kohler reserves the right to change product specifications, design, and standard equipment without notice and without
incurring obligation.
*4: Oil amount when the oil level is at the upper level.

Drive system Belt

Clutch type Electric

Suitable machine Z122E, Z121S Z125E, Z125S

Mounting method Parallel linkage

Adjustment of cutting height Dial gauge

Cutting width mm (in.) 1225 (48) 1375 (54)

Cutting height mm (in.) 38 to 114 (1.5 to 4.5)

PRO
Commercial
Deck
(Fabricated
deck)

Weight (Approx.) kg (lbs.) 60 (132) 68 (150)

Blade spindle speed r/s (rpm) 69.1 (4140) *1 61.7 (3700) *1

Blade tip velocity m/s (fpm) 92.0 (18100) *1 92.0 (18100) *1

Blade length mm (in.) 424 (16.7) 475 (18.7)

Number of blades 3

Dimensions

*1: Engine Max rpm

Model RCK48P-124Z RCK54P-127ZA

Total length mm (in.) 880 (34.6) 925 (36.4)

Total width mm (in.) 1552 (61.1) 1710 (67.3)

Total height mm (in.) 340 (13.3)

IMPLEMENT LIMITATIONS

The KUBOTA Machine has been thoroughly tested for proper performance with implements sold or approved by KUBOTA.
Use with implements which are not sold or approved by KUBOTA and which exceed the maximum specifications listed
below, or which are otherwise unfit for use with the KUBOTA Machine may result in malfunctions or failures of the machine,
damage to other property and injury to the operator or others. [Any malfunctions or failures of the machine resulting from
use with improper implements are not covered by the warranty.]

5IMPLEMENT LIMITATIONS

Maximum loading weight

Front axle

Wf

Z122E, Z121S,
Z125E, Z125S

A Do not operate with trailer on incline greater than 10 .

98 kg (217 lbs.) 380 kg (837 lbs.) 478 kg (1054 lbs.) 34 kg (75 lbs.) 113 kg (250 lbs.)

Rear axle

Wr

Maximum total

weight

Tongue weight WTowing capacity

W

6 INSTRUMENT PANEL AND CONTROLS

INSTRUMENT PANEL AND CONTROLS

ILLUSTRATED CONTENTS ILLUSTRATED CONTENTS

(1) Parking brake lever.............................. 9, 17 (8) Cutting height control dial..................... 22

(2) Motion control lever.............................. 9, 18 (9) Key switch............................................ 11

(3) Seat belt............................................... 16 (10) Hour meter........................................... 12

(4) Cup holder............................................ - (11) PTO switch........................................... 23

(5) Operator's seat..................................... 16 (12) Throttle lever........................................ 17

(6) ROPS................................................... - (13) Light switch (Z121S, Z125S)................ 16

(7) Mower lift pedal.................................... 17

ILLUSTRATED CONTENTS

(1) Anti-scalp roller (Front, bolt shift type)....... 22

7INSTRUMENT PANEL AND CONTROLS

8MOWER MOUNTING

MOWER MOUNTING

MOUNTING THE MOWER DECK

To avoid serious injury:

A Park the machine on a firm and level surface.
A Apply the parking brake.
A Stop the engine and remove the key.

1. Before mounting the mower deck, raise the lift links to
the full up position.

2. Adjust the cutting height control dial to 1.5 in. position.

3. Change the direction of the front tires as shown in the
figure.

4. Place the mower deck at the right side of the machine.

7. Attach the PTO belt to the engine pulley. Refer the belt
routing.

5. Slide the mower deck under the machine, then lower
mower lift links.

6. Attach the lift links to the mower deck with attaching
hardware.

(1) Lift link
(2) Clevis pin, snap pin

(1) PTO belt
(2) Engine pulley

8. After mounting the mower, check the mower level. If
necessary, adjust the mower level and anti-scalp
rollers.

ADJUSTING THE MOWER

See "OPERATING THE MOWER" section.

DISMOUNTING THE MOWER DECK

For dismounting the mower deck, reverse the above
procedures.

OPERATING THE ENGINE

STARTING THE ENGINE

9OPERATING THE ENGINE

To avoid serious injury:
A Read and understand "SAFE OPERATION" in

the front of this manual.

A Read and understand the danger, warning and

caution labels located on the machine.

A To avoid danger of exhaust fume poisoning, do

not operate the engine in a closed building
without proper ventilation.

A Never start the engine while standing on the

ground. Start the engine only from operator's
seat.

1. Sit on the operator's seat.

2. Apply the parking brake.

MOUNT AND DISMOUNT MACHINE
SAFELY

DO NOT step on either side of the mower deck when
mounting and dismounting the machine. When mounting
the machine from either side, step over the mower deck.

(1) Parking brake lever "ENGAGED"

To apply the parking brake:

Place the parking brake lever in the "ENGAGED"
position.

"DISENGAGED"

To release the parking brake:

Place the parking brake lever in the "DISENGAGED"
position.

OPERATING THE ENGINE10

3. Make sure that the PTO switch is in the
"DISENGAGED" (OFF) position.

(1) PTO switch "ENGAGED" (ON)

"DISENGAGED" (OFF)

4. Place the motion control levers in the
"NEUTRAL LOCK" position.

5. Set the throttle lever as follows.

A If the engine is cold:

Place the throttle lever to the "CHOKE" position.

A If the engine is warm:

Place the throttle lever midway between the "SLOW"
and the "FAST" positions.

(1) Throttle lever "FAST"

"SLOW"
"CHOKE"

(1) Motion control lever (LH)
(2) Motion control lever (RH)

(A) "NEUTRAL LOCK"
Position
(B) "NEUTRAL" Position
(held by hands)
(C) "FORWARD"
(D) "REVERSE"

6. Insert the key into the key switch. Turn
the key switch to the "START" position
and release the key to the "ON" position
when the engine starts.

A Because of the start interlocks, the engine can not be

started except when the PTO switch is disengaged
(OFF), the parking brake lever is applied, motion
control levers are in "NEUTRAL LOCK" position and
the operator is sitting on the seat.

11OPERATING THE ENGINE

BThrottle Lever

Pulling the throttle lever backward decreases the engine
speed and pushing it forward increases the engine speed.
When the lever is pushed beyond the "FAST" position, the
choke is engaged.

[For a Cold Engine]

Always place the throttle lever to the "CHOKE" position to
start the engine in cold conditions.

Gradually return the throttle lever to the usual position
after the engine starts and warms up.

The engine/equipment may be operated during the warm­up period, but it may be necessary to leave the choke
partially on until the engine warms up.

[For a Warm Engine]

Always place the throttle lever to the usual position after
the engine starts.

BKey Switch

OFF............ The position where the key can be

inserted into or removed from the
key switch. [When the key is turned
to this position, the engine shuts off.]

ON.............. The engine keeps running.

START........ Apply the parking brake and turn the

key switch to this position to start the
engine.

: "OFF"
: "ON"

A Do not use starting fluid or ether.
A To protect the battery and the starter, make sure that

the starter is not continuously turned for more than 10
seconds at a time.
If the engine does not start, allow 60 seconds cool
down period between starting attempts.

A If the starter does not turn the engine over, shut off the

starter immediately. Do not make further attempts to
start the engine until the condition is corrected. Do not
jump start using another battery.
Consult your local KUBOTA dealer.

A Do not turn the key switch to the "START" position

while the engine is running.

A When the temperature is below 0 (32 ), run the

engine at medium speed to warm up the lubricant of
the engine and the transmission for at least 10
minutes. If the machine is operated before the
lubricant is warm enough, the machine life will be
shortened.

A Do not operate the machine under full load until it is

sufficiently warmed up 2 or 3 minutes for temperature
above 0 (32 ).

A When the ambient temperature is less than -15

(5 ), remove the battery from the machine and store
it somewhere warm until the next operation.

: "START"

7. Warm the engine by running at medium

speed.

OPERATING THE ENGINE12

CHECK DURING OPERATING

While operating, make the following checks to see that all
the parts are functioning normally.

BImmediately Stop the Engine if:

A The engine suddenly slows down or accelerates.
A Unusual noises suddenly occur.
A Exhaust fumes suddenly become discolored.

BFuel Gauge

The fuel gauge indicates the fuel level.

(1) Fuel gauge (E) "EMPTY"

(F) "FULL"

A Do not refuel over "F". Fill the tank only to the bottom

of the filler neck in the fuel tank.

A Fill the fuel on a level ground.

BHour Meter

This meter gives readings for the number of hours the
engine has been running.

(1) Hour meter

COLD WEATHER STARTING

If the ambient temperature is below 0 (32 ) and the
engine is very cold, start it in the following manner:

1. Place the throttle lever to the "CHOKE" position.

2. Turn the key switch to the START (" ") position.

A Operate the starter 5 seconds.
A If the engine does not start, wait 10 seconds.
A Repeat this procedure until the engine starts.

3. When the engine starts, release the key to the "ON"
(" ") position.

4. Place the throttle lever midway between the "SLOW"
and the "FAST" positions.