Kubota G21LD,G21HD, G21LD, G21HD Workshop Manual

WORKSHOP MANUAL

KiSC issued 08, 2007 A

G21LD,G21HD

TO THE READER

KiSC issued 08, 2007 A

This Workshop Manual has been prepared to provide servicing personnel with
information on the m echanism, service and m aintenance of G21LD and G 21HD. It is
divided into three parts, “General”, “Mechanism” and “Servicing”.

■ General

Information on the product identification, the general precautions, maintenance
check list, check and maintenance and special tools are described.

■ Mechanism

Information on the construction and function are included. This part should be
understood before proceeding with troubleshooting, disassembling and servicing.

Refer to Diesel Engi ne Mechan ism W orksh op Man ual (C ode No. 9Y021-0 1874) for
the one which has not been described to this workshop manual.

■ Servicing

Information on the troubleshooting, servicing specification lists, tightening torque,
checking and adjusting, disassembling and assembling, and servicing which cover
procedures, precautions, factory specifications and allowable limits.

All information, illustrations and specifications contained in this manual are based on
the latest product information available at the time of publication.

The right is reserved to make changes in all information at any time without notice.

© KUBOTA Corporation 2005

June 2005

G21LD · G21HD, WSM

SAFETY FIRST

KiSC issued 08, 2007 A

SAFETY INSTRUCTIONS

SAFETY INSTRUCTIONS

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 repair or use

this unit.

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.

■ IMPORTANT : Indicates that equipment or property damage could result if instructions are not

followed.

■ NOTE : Gives helpful information.

BEFORE SERVICING AND REPAIRING

• Read all instructions and safety instructions in this
manual and on your machine safety decals.

• Clean the work area and machine.

• Park the machine on a firm and level ground, and set
the parking brake.

• Lower the implement to the ground.

• Stop the engine, and remove the key.

• Disconnect the battery negative cable.

• Hang a “DO NOT OPERATE” tag in operator
station.

1

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

SAFETY INSTRUCTIONS

SAFETY STARTING

• Do not start the engine by shorting across starter
terminals or bypassing the safety start switch.

• Do not alter or remove any part of machine safety
system.

• Before starting the engine, make sure that all shift
levers are in neutral positions or in disengaged
positions.

• Never start the engine while standing on ground.
Start the engine only from operator’s seat.

SAFETY WORKING

• Do not work on the machine while under the influence
of alcohol, medication , or other substances or while
fatigued.

• Wear close fitting clothing and safety equipment
appropriate to the job.

• Use tools appropriate to the work. Makeshift tools,
parts, and procedures are not recommended.

• When servicing is performed together by two or more
persons, take care to perform all work safely.

• Do not work under the machine that is supported
solely by a jack. Always support the machine by
safety stands.

• Do not touch the rotating or hot parts while the engine
is running.

• Never remove the radiator cap while the engine is
running, or immediately after stopping. Otherwise, hot
water will spout out from radiator. Only remove
radiator cap when cool enough to touch with bare
hands. Slowly loosen the cap to first stop to relieve
pressure before removing completely.

• Escaping fluid (fuel or hydraulic oil) un der pressure
can penetrate the skin causing serious injury. Relieve
pressure before disconnecting hydraulic or fuel lines.
Tighten all connections before applying pressure.

AVOID FIRES

• Fuel is extremely flammable and explosive under
certain conditions. Do not smoke or allow flames or
sparks in your working area.

• To avoid sparks from an accidental short circuit,
always disconnect the battery negative cable first and
connect it last.

• Battery gas can explode. Keep sparks and open
flame away from the top of b attery, especially when
charging the battery.

• Make sure that no fuel has been spilled on the engine.

2

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

SAFETY INSTRUCTIONS

VENTILATE WORK AREA

• If the engine must be running to do some work, make
sure the area is well ventilated . Neve r run the eng ine
in a closed area. The exhaust gas contains poisonous
carbon monoxide.

PREVENT ACID BURNS

• Sulfuric acid in batte ry electrolyte is poisonou s. It is
strong enough to burn skin, clothing and cause
blindness if splashed into eyes. Keep electrolyte
away from eyes, hands and clothing. If you spill
electrolyte on yourself, flush with water, and get
medical attention immediately.

DISPOSE OF FLUIDS PROPERLY

• Do not pour fluids into the ground, down a drain, or
into a stream, pond, or lake. Observe relevant
environmental prot ectio n regulati ons whe n disp osing
of oil, fuel, coolant, electrolyte and other harmful
waste.

PREPARE FOR EMERGENCIES

• Keep a first aid kit and fire extingui sher handy at all
times.

• Keep emergency numbers for doctors, ambulance
service, hospital and fire department near your
telephone.

3

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

SAFETY INSTRUCTIONS

SAFETY DECALS

The following safety decals are installed on the machine.
If a decal becomes damaged, illegible or is not on the machine, replace it. The decal part number is listed in
the parts list.

4

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

SAFETY INSTRUCTIONS

5

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

SAFETY INSTRUCTIONS

6

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

SAFETY INSTRUCTIONS

7

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

SPECIFICATIONS

Model G21LD G21HD

Maximum gross power 15.6 kw (21 HP)

Model D782-E2-G21
Type Indirect injection, vertical, water cooled, 4-cycle diesel engine
Number of cylinders 3
Bore and stroke 67.0 × 73.6 mm (2.64 × 2.90 in.)
Total displacement 778 cm
Rated revolution 3000 rpm
Combustion chamber Spherical type (E-TVCS)
Fuel injection pump Bosch MD type mini pump
Governor Centrifugal ball mechanical governor
Injection nozzle Bosch throttle type

Engine

Capacities

Tires

Traveling
speeds

Dimensions

Weight (Without mower deck and grass
collector)

PTO Shaft drive
PTO clutch Belt tension
Revolution (PTO speed) 2576 min
PTO brake Available

Injection timing 0.28 to 0.31 rad (16° to 18°) before T.D.C.
Injection order 1-2-3
Injection pressure 13.73 MPa (140 kgf/cm
Compression ratio 24 : 1
Lubricating system Forced Iubrication by gear pump
Cooling system Pressurized radiator, forced circulation with water pump
Lubricating oil API Service classification CC or CD, Below 0°C (32 °F) : SAE 10W or 10W-30, 0 to 25 °C

Starting system Electric starter (12 V, 1.0 kW)
Battery 51R (12V, 450CCA)
Fuel No.2-D diesel fuel (ASTM D975)

Fuel tank 22L (5.8U.S.gals., 4.8 lmp. gals.)
Engine crankcase 2.8L (2.95 U.S.qts., 2.4 Imp.qts.)
Engine coolant 2.1L (2.2 U.S.qts., 1.8 Imp.qts.)
Recovery tank 0.25 L (0.26 U.S.qts., 0.22 Imp.qts.)
Transmission (Including

HST and cylinder)
Mower gear case oil 0.40L (0.42 U.S.qts., 0.35 Imp.qts.)
Front 16 × 6.50-8 (4PR) Turf
Rear 23 × 10.5-12 (4PR) Turf
Forward 0 to 15.0 km/h (0 to 9.3 mph)
Reverse 0 to 6.0 km/h (0 to 3.8 mph)
Overall length

(with grass collector)
Overall width (with mower) 1280 mm (50.4 in.)
Overall height 1280 mm (50.4 in.) 1450 mm (57.1 in.)
Wheel base 1280 mm (50.4 in.)

Treads

Front 825 mm (32.5 in.)
Rear 780 mm (30.7 in.)

(32 °F to 77 ° F) : SAE 20 or 10W-30, Above 25 °C (77 °F) : SAE 30 or 10W-30

[No.1-D diesel fuel, if temperature is below - 10 °C (14 °F)]

4.5L (4.75 U.S.qts., 3.96 Imp.qts.) 6.0L (6.34 U.S.qts., 5.28 Imp.qts.)

2930 mm (115.4 in.) 2990 mm (117.7 in.)

440 kg (970 lbs) 510 kg (1124 lbs)

3

(47.48 cu.in.)

-1

(rpm)

2

, 1991 psi)

SPECIFICATIONS

W1028929

8

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

Model G21LD G21HD

Steering Electric power steering (EPS)
Transmission Hydrostatic transmission

Brake Internal expanding brake

Mower Model RCK48G18-PRO

Total length 900 mm (35.4 in.)
Total width 1280 mm (50.4 in.)
Total height 315 mm (12.4 in.)
Mounting method Quick joint, parallel linkage
Adjustment of cutting height Dial gauge
Cutting width 1219 mm (48.0 in.)
Cutting height 25 to 102 mm (1.0 to 4.0 in.)
Number of blades 3
Weight (Approx.) 95 kg (209 lbs)
Discharge direction Rear side

Model GCK500 GCK500HD

Grass

collector

The company reserves the right to chage the specifications without notice

Container capacity 500 L (132 U.S.gals, 110 Imp.gals)
Weight (Approx.) 30 kg (66 Ibs) 60 kg (132 Ibs)
Dumping height — 1750 mm (68.9 in.)

SPECIFICATIONS

W1030228

9

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

DIMENSIONS

DIMENSIONS

10

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

DIMENSIONS

11

G GENERAL

KiSC issued 08, 2007 A

GENERAL

KiSC issued 08, 2007 A

CONTENTS

1. IDENTIFICATION............................................................................................. G-1

2. GENERAL PRECAUTIONS ............................................................................ G-2

3. HANDLING PRECAUTIONS FOR ELECTRICAL PARTS AND WIRING..G-3

[1] WIRING...................................................................................................... G-3

[2] BATTERY................................................................................................... G-5

[3] FUSE.......................................................................................................... G-5

[4] CONNECTOR............................................................................................ G-5

[5] HANDLING OF CIRCUIT TESTER......................................................... G-6

4. LUBRICANTS, FUEL AND COOLANT ......................................................... G-7

5. TIGHTENING TORQUES ............................. ....... ...... ....... ...... ....... ...... ....... .... G- 8

[1] GENERAL USE SCREWS, BOLTS AND NUTS................................... G-8

[2] METRIC SCREWS, BOLTS AND NUTS ............................................... G-8

[3] AMERICAN STANDARD SCREWS, BOLTS AND NUTS WITH UNC

OR UNF THREADS ................................................................................. G-9

6. MAINTENANCE CHECK LIST..................................................................... G-10

7. CHECK AND MAINTENANCE......... ...... ...... ....... ...... ....... ...... ....... ............... G-12

[1] DAILY CHECK........................................................................................ G-12

[2] CHECK POINTS OF INITIAL 50 HOURS........................................... G-21

[3] CHECK POINTS OF EVERY 50 HOURS........................................... G-23

[4] CHECK POINTS OF EVERY 100 HOURS......................................... G-29

[5] CHECK POINT OF EVERY 150 HOURS ......................................... G-32

[6] CHECK POINTS OF EVERY 200 HOURS........................................ G-32

[7] CHECK POINTS OF EVERY 300 HOURS......................................... G-34

[8] CHECK POINT OF EVERY 500 HOURS ........................................... G-35

[9] CHECK POINT OF EVERY 1500 HOURS ......................................... G-36

[10]CHECK POINT OF EVERY 3000 HOURS ......................................... G-36

[11]CHECK POINTS OF EVERY 1 YEAR................................................ G-37

[12]CHECK POINTS OF EVERY 2 YEARS.............................................. G-40

[13]OTHERS .................................................................................................. G-43

8. SPECIAL TOOLS.......................................................................................... G-44

[1] SPECIAL TOOLS FOR ENGINE .......................................................... G-44

[2] SPECIAL TOOLS FOR MACHINE........................................................ G-50

9. IMPLEMENT LIMITATIONS.......................................................................... G-55

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

1. IDENTIFICATION

G GENERAL

(1) Engine Serial Number
(2) Machine Serial Number

(3) Mower Serial Number
(4) Hour Meter

W1010714

G-1

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

2. GENERAL PRECAUTIONS

• During disa ssembly, ca refully ar range removed parts in a cle an
area to prevent confusion later. Screws, bolts and nuts should be
installed in their original position to prevent reassembly errors.

• When special tools are requi red, use KUBOT A genuine speci al
tools. Special tools which are not frequently used should be
made according to the drawings provided.

• Before disassembling or servicing electrical wires, always
disconnect the ground cable from the battery first.

• Remove oil and dirt from parts before measuring.

• Use only KUBOTA genuine parts for parts replacement to
maintain machine performance and to assure safety.

• Gaskets and O-rings must be replaced during reassembly.
Apply grease to new O-rings or oil seals before assembling.
See the figure left side.

• When reassem bling external snap rings or inte rnal snap rings,
they must be positioned so that sharp edge faces against the
direction from which a force is applied. See the figure left side.

• When insert ing spring pins, their splits must face the direction
from which a force is applied. See the figure left side.

• To prevent dam age to the hydraulic s ystem, use only sp ecified
fluid or equivalent.

(1) Grease
(2) Force
(3) Sharp Edge
(4) Axial Force
(5) Rotating Movement

G GENERAL

(A) External Snap Ring
(B) Internal Snap Ring

W1010904

G-2

G21LD · G21HD, WSM

IMPORTANT■

KiSC issued 08, 2007 A

G GENERAL

3. HANDLING PRECAUTIONS FOR ELECTRICAL PARTS
AND WIRING

To ensure safety and prevent damage to the machine and
surrounding equipm ent, heed the following pr ecautions in handling
electrical parts and wiring.

• Check electrical wiring for damage and loosened
connection every year. To this end, educate the customer to
do his or her own check and at the s ame time recommend
the dealer to perform periodic check for a fee.

• Do not attempt to modify or remodel any electrical parts and
wiring.

• When removing th e ba tter y cab le s, dis co nn ect t he n egat ive
cable first. When in stalling the b attery cables, c onnect the
positive cable first.

(1) Negative Terminal (2) Positive Terminal

W1011114

[1] WIRING

• Securely t ighten wiring terminals.

(1) Correct

(Securely tighten)

(2) Incorrect

(Loosening leads to faulty contact)

W1011216

• Do not let wiring contact dangerous part.

(1) Dangerous Part
(2) Wiring (Incorrect)

(3) Wiring (Correct)
(4) Dangerous Part

• Securely insert grommet.

(1) Grommet (A) Correct

(B) Incorrect

W1011313

W1011388

G-3

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

G GENERAL

• Securely clamp, being careful not to damage wiring.

(1) Clamp

• Wind Clamp Spirally

(2) Wire Harness

(3) Clamp
(4) Welding Dent

W1011458

• Clamp wiring so that there is no twist, unnecessary sag, or
excessive tension, except for movable part, where sag be
required.

(1) Wiring
(2) Clamp

(A) Correct
(B) Incorrect

W1011587

• In installing a part, take care not to get wiring caught by it.

(1) Wiring (A) Incorrect

W1011670

• After installing wiring, check protection of terminals and clamped
condition of wiring, only connect battery.

(1) Cover

• Securely Install Cover
W1011735

G-4

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

[2] BATTERY

[3] FUSE

G GENERAL

• Take care not to confuse positive and negative terminal posts.

• When removing b attery cables, disconnect negative cable first.
When installing battery cables, check for polarity and connect
positive cable first.

• Do not install a ny battery with capacity other than is specified
(Ah).

• After connecting cables to battery terminal posts, apply high
temperature grease to them a nd sec urely in stall t erminal covers
on them.

• Do not allow dirt and dust to collect on battery.

CAUTION

• Take care not to let battery liquid spill on your skin and
clothes. If contaminated, wash it off with water immediately.

• Before recharging the battery, remove it from the machine.

• Before recharging, remove cell caps.

• Do recharging in a well- ventilated place where there is no
open flame nearby, as hydrogen gas and oxygen are formed.

W1011816

[4] CONNECTOR

• Use fuses with specified capacity.
Neither too large or small capacity fuse is acceptable.

• Never use steel or copper wire in place of fuse.

• Do not install working light, radio set, etc. on machine which is not
provided with reserve power supply.

• Do not install accessories if fuse capacity of reserve power
supply is exceeded.

(1) Fuse (2) Slow Blow Fuse

W1012092

• For connector with lock, push lock to separate.

(A) Push

W1012211

• In separating connectors, do not pull wire harnesses.

• Hold connector bodies to separate.

(A) Correct (B) Incorrect

W1012272

G-5

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

G GENERAL

• Use sandpaper to remove rust from terminals.

• Repair deformed terminal. Make certain there is no terminal
being exposed or displaced.

(1) Exposed Terminal
(2) Deformed Terminal

(3) Sandpaper
(4) Rust

W1012346

• Make certain that there is no female connector being too open.

(A) Correct (B) Incorrect

W1012430

• Make certain plastic cover is large enough to cover whole
connector.

(1) Cover (A) Correct

[5] HANDLING OF CIRCUIT TESTER

• Use tester correctly following manual provided with tester.

• Check for polarity and range .

(B) Incorrect

W1054624

W1012684

G-6

G21LD · G21HD, WSM

NOTE■

KiSC issued 08, 2007 A

4. LUBRICANTS, FUEL AND COOLANT

G GENERAL

Place

1 Fuel

Cooling
system

2Coolant

Recovery
tank

3 Engine crankcase

Transmission (Including

4

HST & cylinder)

5 Mower gear case

King pin (Left and right)
Center pin
PTO tension arm

6

Universal joint
Side blade shaft
Center blade shaft
Mower tension arm
Speed control pedal shaft
Lift lever shaft
Brake pedal shaft

7

PTO lever fulcrum
Anti-scalp roll er
Speed control link
Accelerator cable

Capacity

G21LD G21HD

22 L

5.8 U.S.gals.

4.8 Imp.gals.

2.1 L

2.2 U.S.qts.

1.8 Imp.qts.

0.25 L

0.26 U.S.qts.

0.22 Imp.qts.

2.8 L *

2.95 U.S.qts.

2.4 Imp.qts.

4.5 L

4.75 U.S.qts.

3.86 Imp.qts.

0.40 L

0.42 U.S.qts.

0.35 Imp.qts.

Until grease overflows

Moderate amount Oil or spray type grease

6.0 L

6.34 U.S.qts.

5.28 Imp.qts.

[ASTM D975]
No. 2-D diesel fuel
No. 1-D diesel fuel if temperature is below

−10 °C (14 °F)

Fresh clean water (soft water) with anti­freeze

Engine oil : API Service Classification
CD, CE or CF
Below 0 °C (32 °F) : SAE10W, 10W-30
or 10W-40
0 to 25 °C (32 to 77 °F): SAE20, 10W-30
or 10W-40
Above 25 °C (77 °F): SAE30, 10W-30 or
10W-40

KUBOTA UDT or SUPER UDT fluid

SAE #90 gear oil

Multipurpose grease
NLGI-2 or NLGI-1 (GC-LB)

Lubricants

• * : Oil amount when the oil level is at the center of the oil level gauge.

G-7

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

G GENERAL

5. TIGHTENING TORQUES

[1] GENERAL USE SCREWS, BOLTS AND NUTS

Screws, bolts, and nuts whose tightening torques are not specified in this Workshop Manual should be

tightened according to the table below.

Indication on top of

bolt

Material of bolt SS400, S20C S43C, S48C

Material of opponent

part

Unit
Diameter

M6

(6 mm, 0.24 in.)

M8

(8 mm, 0.31 in.)

M10

(10 mm, 0.39 in.)

M12

(12 mm, 0.47 in.)

M14

(14 mm, 0.55 in.)

M16

(16 mm, 0.63 in.)

M18

(18 mm, 0.71 in.)

M20

(20 mm, 0.79 in.)

No-grade or 4T 7T 9T

SCr435,
SCM435

Ordinariness Aluminum Ordinariness Aluminum Ordinariness

N·m kgf·m ft-lbs N·m kgf·m ft-lbs N·m kgf·m ft-lbs N·m kgf·m ft-lbs N·m kgf·m ft-lbs

7.85

0.80

5.79

7.85

0.80

5.79

9.81

1.00

7.24

7.85

0.80

5.79

12.3

to

9.31

17.7
to

20.5

39.3
to

45.1

62.8
to

72.5

108

to

125
167

to

191
246

to

284
334

to

392

to

0.95

1.8
to

2.1

4.0
to

4.6

6.4
to

7.4

11.0
to

12.8

17.0
to

19.5

25.0
to

29.0

34.0
to

40.0

to

6.87

13.1
to

15.1

29.0
to

33.2

46.3
to

53.5

79.6
to

92.

123

to

141
181

to

209
246

to

289

to

to

8.82

0.90

16.7

19.6

31.4

34.3

5

1.7

to

to

2.0

3.2

to

to

3.5

–––

–––

–––

–––

–––

to

6.50

12.3
to

14.4

23.2
to

25.3

to

11.2

23.6
to

27.4

48.1
to

55.8

77.5
to

90.2

124

to

147
197

to

225
275

to

318
368

to

431

to

1.15

2.4
to

2.8

4.9
to

5.7

7.9
to

9.2

12.
to

15.0

20.0
to

23.0

28.0
to

32.5

37.5
to

44.

to

to

to

to

8.31

8.82

0.90

6.50

17.4

17.7

to

20.2

20.5

35.5

39.3

to

41.2

44.1

57.2

62.8

to

66.5

72.5

6

91.2
to

108
145

to

166
203

to

235
272

to

0

318

1.8

13.1

to

to

2.1

4.0

to

4.5

6.4

to

7.4

–––

–––

–––

–––

to

15.1

29.0

to

to

32.5

46.3

to

to

53.5

to

14.2

29.5
to

34.3

60.9
to

70.6

103

to

117
167

to

196
260

to

304
344

to

402
491

to

568

1.25
to

1.45

0

3.
to

3.5

6.2
to

7.2

10.5
to

12.0

17.0
to

20.0

26.5
to

31.0

35.0
to

41.0

50.0
to

58.

0
W1034542

9.05
to

10.4

21

to

25.3

44.9
to

52.0

76.0
to

86.7

123

to

144
192

to

224
254

to

296
362

to

419

.7

[2] METRIC SCREWS, BOLTS AND NUTS

Grade

Unit

Nominal
Diameter

M 8 23.6 to 27.4 2.4 to 2.8 17.4 to 20.2 29.4 to 34.3 3.0 to 3.5 21.7 to 25.3
M 10 48.1 to 55.8 4.9 to 5.7 35.5 to 41.2 60.8 to 70.5 6.2 to 7.2 44.9 to 52.1
M 12 77.5 to 90.1 7.9 to 9.2 57.2 to 66.5 103.0 to 117.0 10.5 to 12.0 76.0 to 86.8
M 14 124.0 to 147.0 12.6 to 15.0 91.2 to 108.0 167.0 to 196.0 17.0 to 20.0 123.0 to 144.0
M 16 196.0 to 225.0 20.0 to 23.0 145.0 to 166.0 260.0 to 303.0 26.5 to 31.0 192.0 to 224.0

N·m kgf·m ft-lbs N·m kgf·m ft-lbs

Property class 8.8 Property class 10.9

W1016172

G-8

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

G GENERAL

[3] AMERICAN STANDARD SCREWS, BOLTS AND NUTS WITH UNC OR

UNF THREADS

Grade

Unit

Nominal Diameter

5/16 23.1 to 27.8 2.35 to 2.84 17.0 to 20.5 32.5 to 39.3 3.31 to 4.01 24.0 to 29.0

3/8 47.5 to 57.0 4.84 to 5.82 35.0 to 42.0 61.0 to 73.2 6.22 to 7.47 45.0 to 54.0
1/2 108.5 to 130.2 11.07 to 13.29 80.0 to 96.0 149.2 to 179.0 15.22 to 18.27 110.0 to 132.0

9/16 149.2 to 179.0 15.22 to 18.27 110.0 to 132.0 217.0 to 260.4 22.14 to 26.57 160.0 to 192.0

5/8 203.4 to 244.1 20.75 to 24.91 150.0 to 180.0 298.3 to 358.0 30.44 to 36.53 220.0 to 264.0

SAE GR.5 SAE GR.8

N·m kgf·m ft-lbs N·m kgf·m ft-lbs

W1022485

G-9

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

6. MAINTENANCE CHECK LIST

G GENERAL

Period

No.

Item

1 Tires Check ✩ G-23
2 Battery condition Check ✩ ✩✩✩ ✩Every 100 Hr G-31
3 Safety device Check ✩ G-27
4 Engine oil Change ★✩ ✩✩✩ ✩Every 100 Hr G-21
5 Engine oil filter cartridge Change ★✩✩Every 200 Hr G-21
6 Transmission fluid Change ✩✩Every 300 Hr G-34
7 Transmission oil filter cartridge Replace ★✩ ✩Every 300 Hr G-22
8 Transmission oil strainer Clean ✩✩Every 300 Hr G-35

Hydraulic hose

9

Fuel lines

10

11 Fuel filter

12 Radiator hose and clamp

Check ✩✩ Every 200 Hr G-33
Replace Every 2 Years* G-41
Check ✩ ✩✩✩ ✩Every 100 Hr G-29
Replace
Check ✩ ✩✩✩ ✩Every 100 Hr G-29
Replace
Check ✩✩ Every 200 Hr G-32
Replace

Every 50 Hr

50 100 150 200 300 400 450 500 After

1

1

1

Hour meter reading

Reference

page

Every 2 Years* G-40

✩ Every 500 Hr G-35

Every 2 Years* G-40
13 Radiator core Clean ✩ ✩✩✩ ✩Every 100 Hr** G-29
14 Cooling system Clean Every 1 Year G-37
15 Coolant Change Every 1 Year G-37

16 Air cleaner element

17 Fan belt tension Adjust ✩ G-24
18 Front PTO belt tension Adjust ✩**** G-26
19 Brake play Adjust
20 Greasing – ✩ G-25
21 Fuel injection nozzle Check Every 1500 Hr 1-S54
22 Injection pump Check Every 3000 Hr 1-S52

Clean ✩** G-26
Replace Every 1 Year** G-37

1

✩ G-23

W1035769

G-10

G21LD · G21HD, WSM

IMPORTANT■

KiSC issued 08, 2007 A

G GENERAL

Period

No.

Item

Check ✩✩ Every 200 Hr G-33

23 Intake ai r li n e

Replace Every 2 Years G-41

24 Grass collector net Check ✩*** G-20

Replace Every 1 Year* G-39
25 Mower gear box oil Change ★✩✩✩Every 150 Hr G-22
26 Mower gear box oil seal Replace Every 2 Years* G -42

• ★ : The maintenance indicated by ★ must be done initially.

• * : Replace only if necessary.

• ** : This maintenance shou ld be done more often in dusty conditi ons than in normal conditions.

• *** : This check should be done daily.

• ****: Initial elongation of the front PTO belt may occur prior to 25 hours. Adjust the tension spring length as needed to maintain
belt tension.

• 1 : These items should be serviced by an authorized KUBOTA Dealer, unless the owner has the proper tools and is mechanically

proficient.

• @ : The items listed above (@ marked) are registered as emission related critical parts by KUBOTA in the U.S. EPA nonroad
emission regulation.

Every 50 Hr

50 100 150 200 300 400 450 500 After

Hour meter reading

Reference

page

W1027342

G-11

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

G GENERAL

7. CHECK AND MAINTENANCE

CAUTION

• Be sure to check and service the machine on a flat place with engine shut off, the key removed, the parking
brake on and chock the wheels.

• Do not put yourself below the raised grass collector.

• If it must be going below the raised collec tor to do some wo rk, make sure the raised collector is securely
supported.

[1] DAILY CHECK

To prevent trouble from occurring, it is important to know the condition of the machine. Check the following items

before starting.

Checking

• Check areas where previous trouble was experienced

• Walk around the machine.

1. The tire pressu re , wear and damage .

2. Oil and water leak.

3. Engi ne oil leve l.

4. Coolant level in the recovery tank.

5. Damage of machine body, tightness of all screws, bolts and nuts.

6. Radiator screen.

7. Panel screen.

8. Brake play.

9. Oiling.

10.Fuel level.

11.Air cleaner.

•Mower.

1. Make sure blade bolts are tight.

2. Check blades for wear or damage.

3. Check all hardware.

4. Make sure all pins are in place.

• Grass Collector.

1. Check grass collector net material for deterioration, wear and damage.

2. Tightness of all bolts and nuts.

3. Make sure all pins are in place.

4. Check all hardware.

5. Oiling.

• While sitting in the operator’s seat.

1. Speed control pedal.

2. Brake pedal.

3. Parki ng brak e.

4. Steering wheel.

• Turning the key switch “ON”.

1. Per forma nc e of the easy ch ec ker lig ht.

2. Head lights.

• Starting the engine.

1. Color of the exhaust fumes.

2. Safety start switch, seat safety control and another safety devices.

3. Check for abnormal noise and vibration.

G-12

G21LD · G21HD, WSM

■

IMPORTANT■

KiSC issued 08, 2007 A

G GENERAL

Checking Engine Oil Level

CAUTION

• To avoid personal injury : Always stop the engine and
remove the key before checking oil.

1. Check engi ne oi l befo re starti ng and 5 minut es or more afte r the
engine has stopped.

2. Wipe dipstick area clean.

3. To check the oil level, remove the dipstick (2), wipe it clean,
replace it, and draw it out again. Check to see that the oil level is
between the two notches.

4. Add new oil to the prescribed level at the oil port if necessary.

IMPORTANT

• Use the specified engine oil.
Refer to “LUBRICANTS, FUEL AND COOLING WATER”.
(See page G-7)

• When using new oil of a different maker or viscosity from the
previous one, drain all used oil.
Never mix two different types of oil.

(1) Oil Inlet Plug
(2) Dipstick

(A) Upper Level
(B) Lower Level

W1021025

Checking Transmission Fluid Level

1. Park the machine on a level ground.

2. To check the oil level, remove the dipstick (1), wipe it clean,
replace it and draw it out again.

3. Check to see that the oil level is between the upper (A) and lower
(B) levels.

4. Add new oil to the prescribed level if necessary.

• Use the specified transmission fluid.

• Refer to “LUBRICANTS, FUEL AND COOLANT”.
(See page G-7.)

(1) Dipstick
(2) Oil Inlet Plug
(3) Cover

(A) Upper Level
(B) Lower Level
[a] G21LD
[b] G21HD

W1014533

G-13

G21LD · G21HD, WSM

IMPORTANT■

NOTE■

KiSC issued 08, 2007 A

G GENERAL

Checking Amount of Fuel and Refueling

CAUTION

• Handle fuel carefully. If the engine is running, do not fill the
fuel tank. If engine is hot, let engine cool several minutes
before adding fuel. Do not smoke while filling the fuel tank
or servicing the fuel system. Fill fuel tank only to bottom of
filler neck.

1. Check the fuel level.

2. Take care that the fuel tank does not become empty.

Fuel tank capacity 22 L (5.8 U.S.gal.)

• Use diesel fuel only

1. Use No.2 diesel fuel.

2. Use No.1 diesel fuel if the temperature is below –10 °C (14 °F).

3. Always use a strainer when refueling to prevent fuel injection
pump contamination.

• No.2-D is a distillate fuel of lower volatility for engines in
industrial and heavy mobile service.
(SAE J313 JUN87)
Grade of diesel fuel oil according to ASTM D975

Flash Point

°C (°F)

Min Max Max Max

52

(125)

Water and
Sediment,

volume %

0.05 0.35 0.01

Carbon Residue

on, 10 percent

Residuum, %

Ash, weight %

Distillation

Temperatures

°C (°F)

90 % Point
Min Max Min Max Min Max Max M ax Min
282

(540)

338

(640)

Viscosity

Kinematic

cSt or mm

at 40 °C

1.9 4.1 32.6 40.1 0.50 No.3 40

Viscosity

2

saybolt,

/s

SUS

at 100 °F

Sulfur,
weight

%

Copper

strip

Corrsion

Catane

Number

W1021324

G-14

G21LD · G21HD, WSM

IMPORTANT■

NOTE■

NOTE■

KiSC issued 08, 2007 A

G GENERAL

Radiator Screen and Panel Screen

Daily or after every 5 hours of operation, c heck to be sure the
radiator screen (1) and p anel sc reen (2) are clean . Dirt or c haff on
the radiator screen (1) or radiator core decrease cooling
performance.

1. Remove the radiator screen (1) and remove all foreign material.

2. Remove the dust from between the fins and the tube.

3. If scale forms in the tube, clean with scale inhibitor or its

equivalent.

4. Each time the panel screen is covered with grass during

operation, wipe off the screen with hand. Check the radiator

screen (1) from time to time if grass often gets on it.

5. If dust or chaff is accumulated inside of the panel, clean the

inside of the panel.

• Be sure to stop the engine before cleaning the radiator
screen.

(1) Radiator Screen (2) Panel Screen

W1022263

Retightening Mower Blade Screw

CAUTION

• To avoid injury, always handle the mower blade with care.

1. Dismount the mower and turn it over to expose the mower
blades.

2. Wedge a wooden bloc k (1) securely b etween the mower blade
and mower deck.

3. Retighten the mower blade screw to the specified torque.

4. If the mower blade screw (2) is worn or broken, replace it.

• The screw of the red-painted mower blade is of inverse
helical type.

88.2 to 117.6 N·m

Tightening torque Mower blade screw

(1) Wooden Block
(2) Mower Blade Screw

(A) LOOSEN
(B) TIGHTEN

9.0 to 12.0 kgf·m

65.1 to 86.8 ft-lbs

W1022525

Checking Mower Blade

1. Check the cutting edge of mower blade.

2. Sharpen the cutting edges , if the mo wer b lad es are as s hown in
figure (2).

3. Replace the mower blades, if they are as shown in figure (3).

• To sharpen the mower blades by yourself, clamp the mower
blade securely in a vise and use a la rge mill file along the
original bevel.

• To balance the mower blade, place a small rod through the
center hole and check to see if the blade balances
evenly.File heavy side of the blade until it balance out even.

(1) New Blade
(2) Worn Blade

(3) Cracked Blade

W1022841

G-15

G21LD · G21HD, WSM

■

KiSC issued 08, 2007 A

G GENERAL

Oiling [G21LD, G21HD]

CAUTION

• Be sure to stop the engine and remove the key before oiling.

Oil the following points before starting.

NOTE

• Oil these points on both sides of the machine.

1. Apply oil to the following points.

(1) Link Fulcrum
(2) PTO Lever (Fulcrum) and PTO cable
(3) Front PTO Cable

(4) Brake Pedal
(5) Seat Adjuster

W1030315

G-16

G21LD · G21HD, WSM

■

KiSC issued 08, 2007 A

G GENERAL

Oiling [G21LD, G21HD] (Continued)

CAUTION

• Be sure to stop the engine and remove the key before oiling.

Oil the following points before starting.

NOTE

• Oil these points on both sides of the machine.

1. Apply oil to the following points.

(6) Speed Control Pedal Shaft
(7) Throttle Cable
(8) Mower Univerdsl Joint
(9) Front Link

(10) Around the hole of the Mower Link
(11) Around the Link
(12) Pivo t of Mower Link
(13) Pivo t of Liftarm

W1054445

G-17

G21LD · G21HD, WSM

■

KiSC issued 08, 2007 A

G GENERAL

Oiling [G21LD]

CAUTION

• Be sure to stop the engine and remove the key before oiling.
NOTE

• Oil these points on both sides of the machine.

1. Oil the following points before starting.

(1) L Pin
(2) Latch
(3) Linkage
(4) Guide Hole
(5) Duct Rod Link

(6) Grass Collector Linkages
(7) Grass Collector Cable
(8) Around the Pin
(9) Around the Hole of the Launching

Plate Link

W1013174

G-18

G21LD · G21HD, WSM

■

KiSC issued 08, 2007 A

G GENERAL

Oiling [G21HD]

CAUTION

• Be sure to stop the engine and remove the key before oiling.

Oil the following points before starting.

NOTE

• Oil these points on both sides of the machine.

1. Apply oil to the following points.

(1) Grass Catcher Cable
(2) Pin
(3) Quick Clean Lever Link

(4) Back Cover Link
(5) Back Cover Pivot

W1030878

G-19

G21LD · G21HD, WSM

■

KiSC issued 08, 2007 A

G GENERAL

Checking Grass Collector Net

CAUTION

• Be sure to stop engine before c hecking the grass collector
net condition.

• The grass collector net material is subject to deterioration
and wear. Check it frequently. Use only genuine
replacement net from KUBOTA.

• Make sure all shields and guards are securely in place
following all service, cleaning, or repair work.

[G21LD]

1. The grass collector net (1) is made of cloth and plastic.

2. Check grass collector net (1) for deterioration, wear and damage.

3. A fter inspection, if the grass collector net ( 1) is found worn or
deteriorated, replace it.

4. I f the g rass co ll ec tor net ( 1) is un us ually dir ty or gr as s s tai ned , it
should be washed with a mild detergent and hung up to dry.

[G21HD]

The grass collector net should be checked daily.

NOTE

• Do not attempt to dry the collector net in clothes dryer!

(1) Grass collector Net [a] G21LD

[b] G21HD

W1020458

G-20

G21LD · G21HD, WSM

■

IMPORTANT■

KiSC issued 08, 2007 A

[2] CHECK POINTS OF INITIAL 50 HOURS

Changing Engine Oil

CAUTION

• Be sure to stop the engine before changing oil.

1. Start and warm up the engine for approx. 5 minutes.

2. Place an oil pan underneath the engine.

3. To dra in the used o il, remo ve the drain pl ug ( 1) at the b ottom o f
the engine and drain the oil completely.

4. Screw in the drain plug (1).

5. Fill new oil up to upper line on the dipstick (3).

IMPORTANT

• When using an oil of different manufacture or viscosity from
the previous one, remove all of the old oil.

• Never mix two different type of oil.

• Use the proper SAE engine oil according to ambient
temperatures.
Refer to “LUBRICANTS, FUEL AND COOLANT”.
(See page G-7)

(1) Drain Plug
(2) Oil Inlet Plug
(3) Dipstick

G GENERAL

(A) Upper Level
(B) Lower Level

W1030749

Replacing Engine Oil Filter Cartridge

CAUTION

• Be sure to stop the engine before changing the oil filter
cartridge.

• Allow engine to cool down sufficiently, oil can be hot and
may cause burns.

1. Remove the engine oil filter cartridge (1) with the filter wrench.

2. Apply a slight coat of oil onto the rubber gasket of new cartridge.

3. To install the new cartridge, screw it in by hand. Over tightening
may cause deformation of rubber gasket.

4. After the cartridge has been replaced, the engine oil level
normally lowers a little. Add engine oil to proper level. Check for
oil leaks around filter gasket.

• To prevent serious damage to the engine, element of
recommended type must be used. Use only a genuine
KUBOTA filter or its equivalent.

(1) Engine Oil Filter Cartridge

W1030949

G-21

G21LD · G21HD, WSM

■

IMPORTANT■

KiSC issued 08, 2007 A

G GENERAL

Replacing Transmission Oil Filter Cartridg e

CAUTION

• Be sure to stop the engine before changing the oil filter
cartridge.

• Allow transmission case to cool down sufficiently ; oil can
be hot and may cause burns.

1. The oil filter cartridge must be changed every 300 service hours.

2. Remove the oil filter cartridge with the filter wrench.

3. Lightly tighten the screw (2) by using a screwdriver.

4. Apply a slight coat of oil onto the cartridge gasket.

5. To install the new cartridge, screw it in by hand.
Over tightening may cause deformation of rubber gasket.

6. After the new cartridge has been replaced, the transmission fluid
level normally lowers a little. Add fluid to proper level. Check for
oil leaks around filter gasket.

IMPORTANT

• To prevent serious damage to hydraulic system, the
replacement filter must be a highly efficient, 10 μm filter.
Use only a genuine KUBOTA filter or its equivalent.

(1) Transmission Oil Filter Cartridge (2) Screw

W1031068

Changing Mower Gear Box Oil

1. Dismount the mower, and place the mower on level ground.

2. Remove the oil inlet plug (2).

3. Remove the drain plug (1), and drain the used oil completely.

4. After draining the used oil, reinstall the drain plug (1).

5. Fill with new oil up to the specified level.

• Use the proper SAE Gear Oil.

• Refer to “LUBRICANTS, FUEL AND COOLANT”.
(See page G-7)

(1) Drain Plug (2) Oil Inlet Plug

W1031440

G-22

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

[3] CHECK POINTS OF EVERY 50 HOURS

Checking Tire Pressure

1. Check the wear and damage or tires.

2. Check the tire pressure.

3. If insufficient, add air. If excessive, reduce air.

Tire pressure

CAUTION

• Always maintain the correct tire pressure. Do not inflate
tires above the recommended pressure.

(1) Ground (A) Insufficient

Front

Rear

(B) Normal
(C) Excessive
(D) Bad

200 kPa

2.0 kgf/cm
28 psi

140 kPa

1.4 kgf/cm
20 psi

G GENERAL

2

2

W1068933

Adjusting Brake Pedal Play

CAUTION

• When making ad just ment s, park t he mach i ne o n a fl at a rea ,
block wheels, stop engine and remove the key.

1. If brake peda l play is not corr ect, loose the lock nu t (2) and turn
the nut (3) in the desired direction until the proper play is
achieved.

2. After adjustment, retighten lock nut securely.

Brake play Factory spec.

(1) Brake Pedal
(2) Lock Nut
(3) Nut
(4) Spring

(A) Brake Pedal Play

15 to 25 mm

0.59 to 0.98 in.

W1069219

G-23

G21LD · G21HD, WSM

IMPORTANT■

KiSC issued 08, 2007 A

G GENERAL

Adjusting Fan Belt Tension

CAUTION

• Be sure to stop the engine and remove the key before
checking belt tension.

1. If the fan drive belt becomes loose, the engine may overheat.

2. To adjust, loosen bolts and turn the alternator to tighten the belt.

3. A fte r adjus tmen t, secur ely tigh ten the bol ts.

Moderate belt tension :

The belt deflect app rox. 10 mm (0.4 in .) when the center of the

belt is depressed with finger pressure of 98 N (10 kgf, 22 lbs).

Fan belt tension Factory spec.

Approx. 10 mm

0.4 in.

• When replacing fan belt, be careful not to catch it on the cap
under the water pump. See the illustration to the left.

(1) Cap
(2) Tension bolt
(3) Alternator
(4) Adjustment bolt

(A) Approx. 10 mm (0.4 in.)

W1069477

G-24

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

G GENERAL

Greasing

CAUTION

• Be sure to stop the engine and remove the key before
greasing.

1. Apply grease to the following points.

(1) King Pin
(2) Center Pin
(3) Mower Universal Joint
(4) Machine Universal Joint
(5) Grease Nipple (Side Blade Shaft

(LH, RH))

(6) Grease Nipple (Center Blade Shaft)
(7) Grease Nipple (Mower Tension Arm)
(8) Grass Collector Rotating Pivot
(9) Tension Lever

W1069765

G-25

G21LD · G21HD, WSM

NOTE■

IMPORTANT■

KiSC issued 08, 2007 A

G GENERAL

Cleaning Air Cleaner Element

1. The air cleaner uses a dry element, never apply oil.

2. Do not touch the filter element except where cleaning is required.
To clean the elemen t, use cle an and dry co mpress ed air on the
inside of the eleme nt. Air pres sure shou ld not exce ed 205 kPa

2

(2.1 kgf/cm

, 30 psi).

• Operating in dusty conditions requires frequent

maintenance.

(1) Air Cleaner Cover
(2) Air Cleaner Element

(3) Evacuator Valve

W1070714

Checking and Adjusting Front PTO Belt Tension

CAUTION

• Always stop the eng ine, set the parking brake, remove the
key, and disengage the PTO lever before working on the
front PTO.

If the front PTO belts slip when the PTO is operating under load,

check the front PTO belt tension and adjust the tension spring
length, as explained below.

1. Engage the PTO lever.

2. Measure tension spring length L.

3. If L is shorter tha n 87 mm (3.43 in.), adjust it with the tension
clutch cable adjusting nut.

• L should be 88 to 90 mm (3.47 to 3.54 in.).

4. After adjustment, tighten the nut securely.

• When replacing the new front P TO belts, L sho uld be 91 to 92
mm (3.58 to 3.62 in.).

• When replacing the front PTO belts, be sure to replace the
complete set. These belts are a matched set.

Front PTO belt tension
(L)

(1) Adjusting Nut

Factory spec.

88 to 90 mm

3.47 to 3.54 in.

W1034175

G-26

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

G GENERAL

Checking Safety Devices

The Safety Devices in your ma chine help to protect you while
operating. Please check this Safety Devices periodically–daily is
best–to test function of the Safety Devices before operation.

CAUTION

To avoid personal injury :

• Do not allow anyone near the machine while testing.

• If the machine does not pass a test, do not operate the
machine.

• Sit on operator’s seat for all tests.

1. Check the following tests before operating t he machine.

2. If the mach ine does not pass one of the following te sts, do not
operate the machine, ch eck the related sa fety switches and the
wiring harness.

Test 1 (Safety Start Control 1)

1. Depress the brake pedal (1) fully.

2. Engage the PTO lever (2).

3. Turn the key switch to “START” position.

4. The engine should not crank.

Test 2 (Safety Start Control 2)

1. Disengage PTO lever (2).

2. Release the brake pedal (1).

3. Turn the key to “START” position.

4. The engine should not crank.

Test 3 (Seat Safety Control 1)

1. Run the engine at half throttle.

2. Engage the PTO lever (2).

3. Stand up. (DO NOT GET OFF THE MACHINE.)

4. Engine should shut off.

Test 4 (Seat Safety Control 2)

1. Run the engine at half throttle.

2. Disengage PTO lever (2).

3. Release the brake pedal (1).

4. Stand up. (DO NOT GET OFF THE MACHINE.)

5. Engine should shut off.

(1) Brake Pedal
(2) PTO Lever
(3) Pin
(4) Joint of Lift Arm
(5) PTO Wire

(A) ENGAGED
(B) DISENGAGED

W1031130

G-27

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

G GENERAL

Checking Safety Devices (Continued)
Test 5 (PTO Safety Control 1)

[G21LD]

1. Dismount the grass collector from the platform.

2. Run the engine at half throttle.

3. Engage the PTO lever (2).

4. Engine should shut off.

[G21HD]

1. Remove the pin (3) of the PTO wire (5).

2. Run the engine at half throttle.

3. Engage the PTO lever (2).

4. Lift the grass collector.

5. Engine should shut off.

6. Be sure to attach the PTO wire (5) to original position.

Test 6 (PTO Safety Control 2)
[G21LD]

1. Run the engine at half throttle.

2. Engage the PTO lever (2).

3. Dump the grass collector.

4. PTO lever (2) automatically disengage.

[G21HD]

1. Run the engine at half throttle.

2. Lower the grass collector.

3. Engage the PTO lever (2).

4. Lift the grass collector.

5. PTO lever (2) automatically disengage.

(1) Brake Pedal
(2) PTO Lever
(3) Pin
(4) Joint of Lift Arm
(5) PTO Wire

(A) ENGAGED
(B) DISENGAGED

W1058728

G-28

G21LD · G21HD, WSM

IMPORTANT■

KiSC issued 08, 2007 A

[4] CHECK POINTS OF EVERY 100 HOURS

Changing Engine Oil

1. See page G-21.

Checking Fuel Lines And Fuel Filter

CAUTION

• Be sure to stop the engine and remove the key when
attempting to make the following checks and changes.

• Never fail to check the fuel lines p eriod ic ally . The fuel lines
are subject to wear and age. Fuel may leak out onto the
running engine, causing a fire.

The fuel line connections should be checked annually or every
100 service hours, whichever comes first.

1. The fuel lines is made o f rubber a nd ages regardles s of ser vice
period.

2. If the fuel line and clamps are found damages o r deteriorated,
replace them.

3. Check fuel filter, if it is clogged by debris, and replace it.

G GENERAL

W1034674

• When the fuel line is disconnected for maintenance or
repair, close both ends of the fuel line with a piece of clean
cloth or paper to prevent dust and dirt from entering. In
addition, particular care must be taken not to admit dust and
dirt into the fuel pump. Entrance of dust and dirt causes
malfunction of the fuel pump.

(1) Pipe Clamps
(2) Fuel Line

(3) Fuel Filter

W1034725

Checking Radiator Core

CAUTION

• Be sure to stop the engine before removing the screen.

1. Remove the radiator screen (1).

2. Check the radiator core (2) for the dust and chaff.

3. If the dust or chaff is accumlated, clean the radiator core
completely. After cleaning, place the screens properly.

(1) Radiator Screen (2) Radiator Core

W1034897

G-29

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

G GENERAL

Checking Battery Condition

CAUTION

• Never remove the vent cap while the engine is running.
Keep electrolyte away from eye s, hand s and clot hes . If you
are spattered with it, wash it away completely with water
immediately and get medical attention.

• Wear eye protection and rubber gloves when working
around battery.

Mishandling the battery shortens the service life and adds to
maintenance costs.
The original battery is a maintenance-free, non accessible type
battery.
If the battery is weak, the engine wi ll be difficult to sta rt and the
lights will become dim. It is important to check the battery
periodically.

(1) Battery

W1035046

G-30

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

G GENERAL

Battery Charging

DANGER

To avoid serious injury or death :

• When the battery is being activated, hydrogen and oxygen

gases in the battery are extremely explosive. Keep open
sparks and flames away from the battery at all times,
especially when charging the battery.

CAUTION

• When charging battery, ensure that the vent caps are
securely in place (if equipped).

• When disconnecting the cables from the battery, start with
the negative terminal first.
When connecting the cables to the battery, start with the
positive terminal first.

• Never check battery charge by placing a metal object across
the posts.
Use a voltmeter or hydrometer.

(For accessible maintainable type batteries with removable vent

caps.)

1. Make sure each electrolyte level is at the bottom of vent wells, if
necessary add distilled water in a well-ventilated area.

2. The water in the electrolyte evaporates during recharging. Liquid
shortage damages the battery. Exc essive liquid s pills over and
damages the machine body.

3. To slow charge the battery, connect the battery positive terminal
to the charger positive terminal and the negative to the negative,
then recharge in the standard fashion.

4. A boost charge is only for emergencies. It will partially charge the
battery at a higher rate and in a short time.
When using a boost-charged battery, it is necessary to recharge
the battery as soon as possible.
Failure to do this will shorten the battery’s service life.

5. When the specific gravity of electrolyte reaches 1.27 to 1.29,
charge has completed.

6. When exchang ing an ol d battery with new o ne, use a battery o f
equal specifications shown in “SPECIFICATIONS”.
(For non-accessible maintenance-free type batteries.)
Maintenance-free, non-accessible batteries are designed to
eliminate the need to add water. Yet the volu me of electrolyte
above plates may even tually becom e depleted d ue to abnor mal
conditions such a s hi gh heat or imp roper reg ulator s etting . Use
a voltmeter to check the state of charge. (See reference chart to
determine if charging is necessary.)

Battery voltage Reference state of charge

12.6 100 % (Full charge)

12.4 75 %

12.2 50 %

12.0 25 %

11.8 0 %

(1) Vent well
(2) Separator
(3) Electrolyte

G-31

A : HIGHEST LEVEL
B : LOW EST LEVEL

W1062448

G21LD · G21HD, WSM

NOTE■

NOTE■

KiSC issued 08, 2007 A

[5] CHECK POINT OF EVERY 150 HOURS

Changing Mower Gear Box Oil

1. See page G-22.

[6] CHECK POINTS OF EVERY 200 HOURS

Changing Engine Oil Fiter Cartridge

1. See page G-21.

Checking Radiator Hose and Clamp

• Check to see if the radiator hoses are properly fixed every
200 hours of operation or 6 months, whichever comes first.

1. I f clamp bands (2) a re loose or water l eaks, tight en clamp band
(2) securely.

2. Replace radiator hoses (1) and tighten clamp bands (2) securely,
if radiator hoses (1) are swollen, hardened or cracked.
Repalce radiator hoses (1) and clamp bands (2) every 2 years or
earlier if checked and found that hoses are swollen, hardened or
cracked.

G GENERAL

W1036280

W1036341

• Take the following actions in the event the coolant
temperature be nearly or more than the boiling point, what is
called “Overheating”.

• Park the machine in a safe place and keep the engine
unloaded idling.

• Don’t stop the engine suddenly, but stop it after about 5
minutes of unloaded idling

• Keep yourself well away from the machine for further 10
minutes or while the steam is belown out.

• Checking that there gets no danger such as burning, get rid
of the causes of overheating and then start the engine again.

(1) Radiator Hose (2) Clamp Band

W1036392

G-32

G21LD · G21HD, WSM

■

KiSC issued 08, 2007 A

G GENERAL

Checking Hydraulic Hose

CAUTION

• Be sure to stop the engine and remove the key before
checking and replacing hydraulic hose.

• Allow transmission case to cool down sufficiently; oil can be
hot and may cause burns.

• When replace the hoses, dismount the grass collector.
(G21LD : See page 2-S 6, G21HD : See “High Dump Grass
Collector” section )

NOTE

• Check to see if the hydraulic hoses are properly fixed every
200 hours of operation.

1. Check to see that all lines and hose clamp s are tight and not
damaged.

2. If hoses and clamp are found worn or damaged, replace or repair
them at once.

(1) Mower Lift Cylinder Hose
(2) Grass Collector Cylinder Hose

[a] G21LD
[b] G21HD

W1036641

Checking Intake Air Line

1. Check to see that hoses and hose clamps are tight and not
damaged.

2. If hoses and clamps are found worn or dam aged, replace them
at once.

(1) Hose (2) Clamp

W1041481

G-33

G21LD · G21HD, WSM

■

KiSC issued 08, 2007 A

[7] CHECK POINTS OF EVERY 300 HOURS

Changing Transmission Fluid

CAUTION

• Be sure to stop the engine and remove the key before
changing or checking the oil.

• Allow transmission case to cool down sufficiently; oil can be
hot and may cause burns.

1. Place the machine on level ground.

2. R emove the drain plug (1) and oil inlet plug (2), and drain the
used oil completely.

3. After draining the oil, reinstall the drain plug (1).

4. Fi ll wi th new oi l up to the uppe r level (A) on the oil level dipst ick
(3).

5. A fter draining , disassem ble and clea n the straine rs and chan ge
the oil filter cartridge. After reassembling, fill with UDT or SUPER
UDT hydraulic transmission fluid, or its equivalent.

6. After running the engine for a few minutes, stop it and check the
oil level again; add oil to the prescribed level.

IMPORTANT

• Operate only at low RPM’s immediately after changing the
transmission fluid and filter cartridge.
Keep the engine at medium speed for a few minutes to
insure proper lubrication of all parts so there is no damage
to transmission.

(1) Drain Plug
(2) Oil Inlet Plug
(3) Oil Level Dipstick
(4) Cover

G GENERAL

(A) Upper Level
(B) Lower Level
[a] G21LD
[b] G21HD

W1036772

Changi ng Transmis s io n O il Filter Cart r i d g e

1. See page G-22.

W1036964

G-34

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

G GENERAL

Cleaning Transmission Oil Strainer

CAUTION

• Be sure to stop the engine and remove the key before
cleaning the transmission oil strainer.

• Allow transmission case to cool down sufficiently; oil can be
hot and may cause burns.

1. Remove 2-M8 bolts.

2. Remove the suction pipe (1) with O ring (2).

3. Clean completely the oil strainer (3) with kerosene.

4. Install the suction pipe (1) with O ring (2).

5. Install the bolts.

(1) Suction Pipe
(2) O-ring

(3) Oil Strainer

W1037015

[8] CHECK POINT OF EVERY 500 HOURS

Replacing Fuel Filter

1. Replace the fuel filters (1).

(1) Fuel Filter

W1037174

G-35

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

[9] CHECK POINT OF EVERY 1500 HOURS

Checking Fuel Injection Nozzle

1. See page 1-S54.

[10] CHECK POINT OF EVERY 3000 HOURS

Checking Injection Pump

1. See page 1-S52.

G GENERAL

W1042838

G-36

G21LD · G21HD, WSM

IMPORTANT■

IMPORTANT■

KiSC issued 08, 2007 A

[11] CHECK POINTS OF EVERY 1 YEAR

Replacing Air Cleaner Element

1. Remove the air cleaner element (2) once a year.

• The air cleaner uses a dry element, never apply oil.

• Do not run the engine with filter element removed.

• Be sure to refit the air cleaner cover (1) as shown in the
figure. If the air cleaner cover (1) is improperly fitted,
evacuator valve (3) will not function and dust will adhere to
the element.

• If it is loose, dust and dirt may be sucked in, wearing down
the cylinder and piston rings earlier and thereby resulting in
poor power output.

(1) Air Cleaner Cover
(2) Air Cleaner Element

Flushing Cooling System and Changing Coolant

CAUTION

• Never open radiator cap when engine is hot.

• When opening, loosen cap slightly to the stop to relieve any
excess pressure before removing radiator cap completely.

G GENERAL

(3) Evacuator Valve

W1037268

1. Stop the engine and let cool down.

2. To drain the coolant, open the radiator drain plug (3) and engine
drain plug (4) and remove the radi ator cap (1). The ra diator cap
(1) must be removed to completely drain the coolant.

3. After all coolant is drained, fill with clean water and cooling
system cleaner.

4. Follow directions of the cleaner instruction.

5. After flushing, fill with clean water and anti-freeze until the coolant
level is just below the port.

6. Fill with clean water and anti -freeze upper lev el of the recovery
tank (2).

7. Start and operate the engine for few minutes.

8. Stop the engine. Check coolant level and add coolant if
necessary.

9. Install the radiator cap (1) securely.

• Do not start engine without coolant.

• Use clean, fresh water and anti-freeze to fill the radiator and
recovery tank.
Refer to “LUBRICANTS, FUEL AND COOLANT”.
(See page G-7)

• When the anti-freeze is mixed with water, the anti-freeze
mixing ratio must be less than 50 %.

• Securely tighten the radiator cap (1). If the cap is loose or
improperly fitted, water may lead out and the engine could
overheat.

(1) Radiator Cap
(2) Recovery Tank
(3) Radiator Drain Plug
(4) Engine Drain Plug

A : Highest Level
B : Lowest Level

W1037402

G-37

G21LD · G21HD, WSM

NOTE■

KiSC issued 08, 2007 A

G GENERAL

Flushing Cooling System and Changing Coolant (Continued)

■ Anti-Freeze

If cooling water freezes, the cylinders and radiator can be
damaged. It is necessary, if the ambient temperature falls below
0 °C (32 °F), to remove coolin g water mix it with anti- freeze and
full the radiator with it.

1. Th ere are two types of anti-freeze av ailable; use the permanent
type (PT) for this engine.

2. Before adding anti-freeze for the first time, clean the radiator
interior by pouring fresh water and draining it a few times.

3. The procedure for mixing of water and anti-freeze differs
according to the maker of the anti-freeze and the ambient
temperature, basical ly should be referred to SAE J1034, more
specially als o to SAE J814c.

4. Mix the anti-freeze with water, and then fill in to the rediator.

Vol % Anti­freeze

40 -24 -12 106 222
50 -37 -34 108 226

Freezing Point Boilling Point*

°C °F °C °F

* At 101 kPa (760 mmHg) pressure (atmospheric). A higher
boiling point is obtained by u sing a radiat or pressure cap which
permits the development of pressure within the cooling system.

• The above date represent industry standards that
necessitate a minimum glycol c ontent in the concentrates
anti-freeze.

• When the cooling water level drops due to evaporation, add
water only. In case of leaka ge, a dd ant i-freeze a nd wa ter in
the specified mixing ratio.

• Anti-freeze abs or bs moisture. Keep unused an ti- f reeze in a
tightly sealed container.

• Do not use radiator cleaning agents when anti-freeze has
been added to the cooling water. (Anti-freeze contains an
anti-corrosive agent, which will react with the radiator
cleaning agent forming sludge which will affect the engine
parts.)

W1037674

G-38

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

G GENERAL

Replacing Grass Collector Net (G21LD)

1. Remove the knob nut (1) from top of grass collector cover.

2. Remove plastic cover (2) from collector.

3. Remove the 2 clevis pins, 2 cotter-pins (3), 2 flange bolts and the
height adjust stay (4) from the top of collector frame.

4. Remove 4-1/4 hex bolts, 7-1/4 curved bolts and bottom plate
from collector frame.

5. Remove the 4-M6 bolts and 2 side beams (6) from collector.

6. Remove the 4-M6 bolts and 2 bottom corner plates (5) from
collector frame.

7. Remov e the 2 curved bol ts (7), 2 hex bolts ( 8), 4 spacers ( 9), 4
plain washers (10), 4 lock was he rs (11) , 4 hex nuts ( 12) , bo ttom
corner plate (14) and pipe frame bag (13) from bag frame.

8. Then remove the hopper net from frame.

9. To attach new or cleaned net (15), reverse the above procedures
and be sure to install removed components.

(1) Knob Nut
(2) Plastic Cover
(3) Cotter-pin
(4) Height Adjust Stay
(5) Bottom Corner Plate
(6) Side Beam
(7) Curved Bolt
(8) Hex Bolt

(9) Spacer
(10) Plain Washer
(11) Lock Washer
(12) Hex Nut
(13) Pipe Frame Bag
(14) Botto m Corner Plate
(15) New or Cleaned Net

W1021670

G-39

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

[12] CHECK POINTS OF EVERY 2 YEARS

Replacing Fuel Line

1. Replace the fuel hoses (1) and hose clamps (2).
Refer to “Checking Fuel Line”. (See page G-29.)

(1) Fuel Hose (2) Hose Clamp

G GENERAL

Replacing Radiator Hose and Clamp Band

1. Replace the radiator hoses (1) and clamp bands (2).
Refer to “Checking Radiator Hose and Hose Clamp” .
(See page G-32.)

(1) Radiator Hose (2) Clamp Band

G-40

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

G GENERAL

Replacing Hydraulic Hoses

CAUTION

• Be sure to stop the engine and remove the key before
checking and replacing hydraulic hose.

• Allow transmission case to cool down sufficiently; oil can be
hot and may cause burns.

• When replace the hoses, dismount the grass collector.
(G21LD : See page 2-S 6, G21HD : See “High Dump Grass
Collector” section)

1. Replace hydraulic hoses and hose clamp every 2 years or earlier
if checked and found that hydraulic hoses are swollen, hardened
or cracked.

(1) Mower Lift Cylinder Hose
(2) Grass Collector Cylinder Hose

[a] G21LD
[b] G21HD

Replacing Intake Air Line

1. Replace intake air line.

(1) Hose (2) Clamp

W1046200

G-41

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

G GENERAL

Replacing Mower Gear Box Oil Seals

1. Replace the mower gear box oil seals (1), (2).
Refer to “Disassembling Gear Box Assembly”.
(See page 9-S14.)

(1) Oil Seal (2) Oil Seal

G-42

G21LD · G21HD, WSM

IMPORTANT■

KiSC issued 08, 2007 A

[13] OTHERS

G GENERAL

Replacing Fuses

1. The electrical system is protected from potential damage by
fuses.
A blown fuse indicates that there is an overload or short
somewhere in the electrical system.

2. If any of the fuses should blow, replace with a new one of the
same capacity.

• Before replacing a blown fuse, determine why the fuse blew
and make any necessary repairs. Failure to follow this
procedure may result in serious damage to the electrical
system.

■ Protected Circuit

FUSE NO.
(ID LABEL)

(a) EPS MT 30

1

(b) E/G STOP 15 Engine stop timer relay
(c) IG/M 10

2 – Slow blow fuse 40

CAPACITY

(A)

Protected circuit

Electric power steering moter
circuit

Fuel pump, head light, power
steering control unit, etc.

Check circuit against wrong
battery connection

(1) Fuse (2) Slow Blow Fuse

Replacing Bulbs
(A) Replacing the head light bulb

1. Open hood.

2. Turn bulb socket to remove socket from headlight housing.

3. Push bulb down and turn one quarter tur n to remove bulb from
the socket.

4. Install new bulb to the socket.

5. Install the socket in housing.

6. Close hood.

Head light bulb Capacity

1.04A / 12.8 Rated
voltage

(B) Replacing the indicator light bulb

1. Open hood.

2. Turn bad bulb socket to the left and remove it.

3. Pull bulb from the socket.

4. Push new bulb into the socket.

5. Install the socket.

6. Close hood.

Indicator light bulb Capacity

0.27A / 14.0 Rated
voltage

G-43

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

8. SPECIAL TOOLS

[1] SPECIAL TOOLS FOR ENGINE

Special Use Puller Set

Code No.: 079 16- 09 032
Application: Use exclusively for pushing out bearing, gears and

Piston Ring Compressor

Code No.: 079 09- 32 111
Application: Use exclusively for pushing in the piston with piston

G GENERAL

other parts with ease.

W1048293

rings into the cylinder.

W1048361

Piston Ring Tool

Code No.: 079 09- 32 121
Application: Use exclusively for removing or installing the piston ring

with ease.

W1048421

Diesel Engine Compression Tester

Code No.: 07909-30208 (Assembly) 07909-31251 (G)

07909-30934 (A to F) 07909-31271 (I)
07909-31211 (E and F) 07909-31281 (J)
07909-31231 (H)

Application: Use to measure diesel engine compression and

diagnostics of need for major overhaul.

(1) Gauge
(2) L Joint
(3) Adaptor A
(4) Adaptor B
(5) Adaptor C
(6) Adaptor E

(7) Adaptor F
(8) Adaptor G

(9) Adaptor H
(10) Adaptor I
(11) Adaptor J

W1048481

G-44

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

G GENERAL

Oil Pressure Tester

Code No.: 07916-32032
Application: Use to measure lubricating oil pressure.

(1) Gauge
(2) Cable
(3) Threaded Joint
(4) Adaptor 1

(5) Adaptor 2
(6) Adaptor 3
(7) Adaptor 4
(8) Adaptor 5

W1048722

Valve Seat Cutter

Code No.: 07909-33102
Application: Use to reseat valves.
Angle: 0.785 rad. (45 °)

0.262 rad. (15 °)

Diameter: 28.6 mm (1.126 in.)

31.6 mm (1.244 in.)

35.0 mm (1.378 in.)

38.0 mm (1.496 in.)

41.3 mm (1.626 in.)

50.8 mm (2.000 in.)

W1048944

Radiator Tester

Code No.: 07909-31551
Application: Use to check of r adiator c ap pressu re, and leak s from

cooling system.

Remarks: Adapter (1) BANZAI Code No. RCT-2A-30S

W1049045

Connecting Rod Alignment Tool

Code No.: 07909-31661
Application: Use to check the connecting rod alignment.
Applicable: Connecting rod big end I.D.
range 30 to 75 mm (1.18 to 2.95 in.) dia.

Connecting rod length
65 to 300 mm (2.57 to 11.81 in.)

W1049118

Flywheel Puller

Code No.: 07916-32011
Application: Use exclusively for removing the flywheel with ease.

W1049723

G-45

G21LD · G21HD, WSM

NOTE■

KiSC issued 08, 2007 A

G GENERAL

Nozzle Tester

Code No.: 079 09- 31 361
Application: Use to check the fuel injection pressure and spray

pattern of nozzle.

Measuring: 0 to 50 MPa

2

range (0 to 500 kgf/cm

, 0 to 7000 psi)

W1049783

Plastigage

Code No.: 079 09- 30 241
Application: Use to check the oil clearance between crankshaft and

bearing, etc..

Measuring: Green.....0.025 to 0.076 mm (0.001 to 0.003 in.)

range Red........0.051 to 0.152 mm (0.002 to 0.006 in.)

Blue.......0.102 to 0.229 mm (0.004 to 0.009 in.)

W1049942

Red Check

Code No.: 079 09- 31 371
Application: Use to check cra cks on cylinder head, cy linder block,

etc..

• The following special tools are not provided, so make them referring to the figure.
Valve Guide Replacing Tool

Application: Use to press out and press fit the valve guide.

A 20 mm dia. (0.79 in. dia.)

B

C

D 200 mm (7.87 in.)
E 80 mm (3.15 in.)
F 40 mm (1.58 in.)

G 15 mm (0.59 in.)

H 5 mm (0.197 in.)

I 6.0 to 6.1 mm dia. (0.236 to 0.240 in. dia.)

J 18 mm dia. (0.71 in. dia.)
K 10.6 to 10.7 mm dia. (0.417 to 0.421 in. dia.)
L 7 mm (0.276 in.)

C1 Chamfer 1.0 mm (0.039 in.)
C2 Chamfer 2.0 mm (0.079 in.)

C0.3 Chamfer 0.3 mm (0.012 in.)

9.96 to 9.98 mm dia.
(0.3921 to 0.3929 in. dia.)

5.5 to 5.7 mm dia.
(0.2165 to 0.2244 in. dia.)

W1050024

W1050106

G-46

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

G GENERAL

Injection Pump Pressure Tester

Application: Use to check fuel tightness of injection pumps.

A
B Copper gasket

C Flange (Material: Steel)
D Hex. nut 27 mm (1.06 in.) across the plat
E Injection pipe
FPF1/2
G 5 mm (0.20 in.)
H 17 mm dia. (0.67 in. dia.)

I 8 mm dia. (0.31 in. dia.)
J 1.0 mm (0.039 in.)

K 17 mm dia. (0.67 in. dia.)

L

M 8 mm (0.31 in.)
N 4 mm (0.16 in.)

O

PPF1/2
Q 23 mm (0.91 in.)
R 17 mm (0.67 in.)
S 4 mm (0.16 in.)

T
U 100 mm (3.94 in.)

V M12 × P1.5

a Adhesive application
b Fillet welding on the enter circumference

Pressure gauge full scale: More than

29.4 MPa (300 kgf/cm

6.10 to 6.20 mm dia.
(0.2402 to 0.2441 in. dia.)

11.97 to 11.99 mm dia.
(0.4713 to 0.4721 in. dia.)

12.00 to 12.02 mm dia.
(0.4724 to 0.4732 in. dia.)

2

, 4267 psi)

W1050289

G-47

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

G GENERAL

Bushing Replacing Tool

Application: Use to press out and to press fit the bushing.

1. For small end bushing

A 145 mm (5.71 in.)
B 20 mm (0.79 in.)
C 100 mm (3.94 in.)

D

E
F 25 mm dia. (0.98 in.dia.)

a6.3 μm (250μin.)
b6.3 μm (250μin.)

19.90 to 19.95 mm dia.
(0.7835 to 0.7854 in.dia.)

21.90 to 21.95 mm dia.
(0.8622 to 0.8642 in.dia.)

2. For idle gear bushing

A 150 mm (5.91 in.)
B 20 mm (0.79 in.)
C 100 mm (3.94 in.)

D

E
F 25 mm (0.98 in.)

a6.3 μm (250μin.)
b6.3 μm (250μin.)

19.90 to 19.95 mm
(0.7835 to 0.7854 in.)

21.90 to 21.95 mm
(0.8622 to 0.8642 in.)

Flywheel Stopper

Application: Use to loosen and tighten the flywheel screw.

A 200 mm (7.87 in.)
B 20 mm (0.79 in.)
C 30 mm (1.18 in.)
D 8 mm (0.31 in.)
E 10 mm dia. (0.39 in. dia.)

W1050660

W1050819

G-48

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

G GENERAL

Crankshaft Bearing 1 Replacing Tool

Application: Use to press out and to press fit the crankshaft bearing

1.

[Press Out]

A 135 mm (5.31 in.)
B 72 mm (2.83 in.)
C40° (1.57 rad.)
D 10 mm (0.39 in.)
E 22 mm (0.87 in.)
F 20 mm dia. (0.79 in.dia.)

G

H

47.90 to 47.95 mm dia.
(1.8858 to 1.8878 in. dia.)

43.90 to 43.95 mm dia.
(1.7283 to 1.7303 in. dia.)

[Press Fit]

A 130 mm (5.12 in.)
B 72 mm (2.83 in.)
C40° (1.57 rad.)
D 9 mm (0.35 in.)
E 24 mm (0.95 in.)
F 20 mm dia. (0.79 in.dia.)
G 68 mm dia. (0.79 in. dia.)

H

39.90 to 39.95 mm dia.
(1.5709 to 1.5728 in. dia.)

W1051113

G-49

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

[2] SPECIAL TOOLS FOR MACHINE

Steering Wheel Puller

Code No.: 079 16- 51 090
Application: Use for removing the steering wheel without damaging

Toe-in Gauge

Code No.: 079 09- 31 681
Application: This allows easy measurement of toe-in for all machine

G GENERAL

the steering shaft.

W1051779

models.

W1051843

Relief Valve Pressure Tester

Code No.: 079 16- 50 045
Application: This allows easy measurement of relief set pressure.

(1) Gauge (07916-50322)
(2) Cable (07916-50331)
(3) Threaded Joint (07916-50401)
(4) Threaded Joint (07916-50341)
(5) Adaptor B (M18 × P1.5)
(07916-50361)

(6) Adaptor C (PS3/8) (07916-50371)
(7) Adaptor D (PT1/8) (07916-50381)
(8) Adaptor E (PS3/8) (07916-50392)
(9) Adaptor F (PF1/2) (07916-62601)

(10) Adaptor 58 (PT1/4) (07916-52391)

W1051907

Pressure Gauge 50

Code No.: 079 16- 52 961
Application: This pressure gauge is used to measure the low oil

pressure.

W1052218

G-50

G21LD · G21HD, WSM

NOTE■

KiSC issued 08, 2007 A

• The following special tool is not provided, so make it referring to the figure.

Steering Wheel Puller Adaptor

G GENERAL

Application: Use for removing the steering wheel with steering wheel

A 22 mm (0.87 in.) F 116 mm (4.57 in.)
B 64 mm (2.52 in.) G 5 mm (0.20 in.)
C 11 mm (0.43 in.) H 9.5 mm (0.38 in.)
D 32 mm (1.26 in.) I 3 mm (0.12 in.)
E 20 mm (0.79 in.) J 5 mm (0.20 in.)

G-51

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

Adaptor Bolt for HST

Application: Use for checking the charge relief valve setting pressure.

A 26 mm (1.02 in.) K 0.4 mm (0.02 in.)
B 18 mm (0.71 in.) L 0.5 mm (0.02 in.)
C 15 mm (0.59 in.) M 15 mm (0.59 in.)
D 30 mm (1.18 in.) N G 3/8
E RP 1/4 O Chamfer 1 mm (0.04 in.)
F 22 mm (0.87 in.) P 8 mm (0.31 in.) dia. drill thru

G 10 mm (0.39 in.) Q 10 mm dia. (0.39 in. dia.)
H 0.8 mm (0.03 in.) R 16.8 mm dia. (0.66 in. dia.)

I 46.5 mm (1.83 in.) S 24.5 mm dia. (0.96 IN. dia.)

J 17 mm (0.67 in.)

G GENERAL

Chamfer 0.5 mm (0.02 in.) (Both ends)

G-52

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

Adaptor for Control Valve

Application: Use for checking the main relief valve setting pressure.

A 40 mm (1.57 in.) I 4.5 mm dia. (0.18 in. dia.)
B 18 mm (0.71.) J 9 mm dia. (0.18 in. dia.)
C 6 mm (0.24 in.) K RP 1/4 thread depth 15 mm (0.59 in.)

D 3 mm (0.12 in.) L 0.5 mm (0.02 in.)
E 3 mm (0.12 in.) M 7/16-20 SAE 37 ° flare
F 0.785 rad. (45 °) N 21 mm (0.83 in.)
G 0.523 rad. (30 °) O 24.2 mm (0.95 in.)
H 0.645 rad. (37 °)

G GENERAL

Drill depth 20 mm (0.79 in.)

G-53

G21LD · G21HD, WSM

■

KiSC issued 08, 2007 A

Flange for Control Valve

1. Use for checking the relief valve setting pressure.

NOTE

• When using , attach with following parts.

1. O-ring: 04811-10240

2. O-ring: 04811-10600.

G GENERAL

A RP 1/4 N 5 mm dia. (0.20 in. dia.)
B 14.5 mm dia. (0.59 in. dia.) O 2.70 to 2.95 mm (0.106 to 0.116 in.)
C 2.09 rad. (120 °) P 2.09 rad. (120 °)
D 20 mm (0.79 in.) Q 20 mm dia. (0.79 in. dia.)
E 3/4-16 UNF R 23.95 to 24.00 mm dia.

(0.9429 to 0.9449 in. dia.)

F Chamfer 1mm (0.04 in.) S 63.00 to 63.05 mm dia.

G 38 mm (1.50 in.) T 76 mm dia. (2.99 in. dia.)
H 18 mm (0.71 in.) U R 0.5 mm (0.02 in.)

I 15 mm (0.59 in.) V 1.4 to 1.5 mm (0.055 to 0.059 in.)
J 1.4 to 1.5 mm (0.055 to 0.059 in.) W 2.70 to 2.95 mm (0.106 to 0.116 in.)
K Chamfer 1mm (0.04 in.) X R 0.5mm (0.02 in.)
L R 0.5 mm (0.02 in.) Y 20 mm (0.79 in.)

M R 0.5 mm (0.02 in.) Z 26 mm (1.02 in.)

(2.4803 to 2.4823 in. dia.)

G-54

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

G GENERAL

9. IMPLEMENT LIMITATIONS

The KUBOTA Machi ne has been thoroughl y tes ted for p roper pe rforman ce wit h impl ements sold or a pprov ed by
KUBOTA. Use of implements which exceed the maximum loading weight listed below, or which are not recommended
for use with the KUBOTA Ma chine m ay result in malfunction s or failur es of the machine, d amage to oth er property
and injury to the operator or others.
(Any malfunctions or fa ilures of the machine resulting from use with improper implements are not covered by the
warranty.)

Maximum axle loading weigh t

G21LD

G21HD

Front axle

Wf

350 kg (770 lbs) 550 kg (1210 lbs) 900 kg (1980 lbs)

Rear axle

Wr

Total gross machine weight

W1054384

G-55

1 ENGINE

KiSC issued 08, 2007 A

SERVICING

KiSC issued 08, 2007 A

CONTENTS

1. TROUBLESHOOTING...................................................................................1-S1

2. SERVICING SPECIFICATIONS ....................................................................1-S5

[1] ENGINE BODY........................................................................................1-S5

[2] L UBR ICATI NG SYSTEM ............................... ...... ....... ...... ....... ...... ....... ...1-S9

[3] COOLING SYSTEM.................................................................................1-S9

[4] FU EL SYSTE M ........................... ...... ...... ....... ...... ....... ...... ....... ...... ....... .1-S10

3. TIGHTENING TORQUES ............................. ....... ...... ....... ...... ....... ...... ....... .1-S11

4. CHECKING, DISASSEMBLING AND SERVICING.....................................1-S12

[1] S EPA RATIN G ENGINE .......................... ....... ...... ....... ...... ....... ...... ....... .1-S12

(1) Disassembling and Assembling........................................................1-S12

[2] ENGINE BODY......................................................................................1-S17

(1) Checking and Adjus ti ng ..................... ....................................... ....... .1-S17

(2) Disassembling and Assembling........................................................1-S20

(3) Servicing ...........................................................................................1-S32

[3] L UBR ICATI NG SYSTEM ............................... ...... ....... ...... ....... ...... ....... .1-S47

(1) Checking ...........................................................................................1-S47

(2) Servicing ...........................................................................................1-S47

[4] COOLING SYSTEM...............................................................................1-S49

(1) Checking and Adjus ti ng ..................... ....................................... ....... .1-S49

(2) Disassembling and Assembling........................................................1-S51

[5] FU EL SYSTE M ........................... ...... ...... ....... ...... ....... ...... ....... ...... ....... .1-S52

(1) Checking and Adjus ti ng ..................... ....................................... ....... .1-S52

(2) Disassembling and Assembling........................................................1-S55

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

1. TROUBLESHOOTING

ENGINE

Symptom Probable Cause Solution

Engine Does Not
Start

No fuel Replenish fuel –
Air in the fuel system Bleed fuel system –
Water in the fuel system Change fuel and

replace fuel system
Fuel pipe clogged Clean fuel pipe –
Fuel filter clogged Replace fuel filter G-35
Excessively high viscosity of fuel or engine oil at

low temperature
Fuel with low cetane number Use specified fuel G-7
Fuel leak due to loose injection pipe retaining nut Tighten retaining nut 1-S55
Incorrect injection timing Adjust injection

Fuel camshaft worn Replace fuel

Injection nozzle clogged Clean injection

Injection pump malfunctioning Repair or replace

Seizure of crankshaft, camshaft, piston, cylinder
or bearing

Compression leak from cylinder Replace head

Improper valve timing Correct valve timing 1-S52
Piston ring and cylinder worn Replace piston ring

Excessive valve clearance Adjust valve

Use specified fuel or

engine oil

timing

camshaft

nozzle

injection pump

Replace crankshaft,

camshaft, piston,

cylinder or bearing

gasket, tighten

cylinder head screw,

glow plug and nozzle

holder

and bore oversize

cylinder

clearance

Reference
Page

–

G-7

1-S52

1-S25

1-S54

1-S52

1-S29, S30

1-S21, S22

1-S28, S46

1-S19

W1014322

1-S1

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

ENGINE

Symptom Probable Cause Solution

Engine Does Not
Start
(Starter Does Not
Run)

Battery discharged Charge battery G-31
Starter malfunctioning Repair or replace

starter

Slow blow fuse blown Replace slow blow

fuse

Main switch malfunctioning Repair or replace

main switch
PTO switch defective Replace PTO switch 8-S24
Brake switch defective Replace brake switch 8-S23
Seat switch defective Replace seat switch 8-S24
Wiring harness disconnected Connect wiring

harness.

Engine Revolution Is
Not Smooth

Fuel filter clogged or dirty Replace fuel filter G-35
Air cleaner clogged Clean or replace air

cleaner element
Fuel leak due to loose injection pipe retaining nut Tighten retaining nut 1-S20
Injection pump malfunctioning Repair or replace

injection pump
Incorrect nozzle injection pressure Adjust nozzle

injection pressure
Injection nozzle stuck or clogged Repair or replace

injection nozzle
Governor malfunctioning Repair governor 1-S25

Either White or Blue
Exhaust Gas Is
Observed

Excessive engine oil Reduce to specified

engine oil level
Piston ring and cylinder worn or sto ck Repair piston ring

and bore oversize

piston
Incorrect injection timing Adjust injection

timing
Deficient compression Adjust top clearance 1-S18

Either Black or Dark
Gray Exhaust Gas Is
Observed

Overload Lessen load –
Low grade fuel used Use specified fuel –
Fuel filter clogged Replace fuel filter G-35
Air cleaner clogged Clean or replace air

cleaner element
Deficient nozzle injection Repair or replace

nozzle

Reference
Page

8-S13

–

8-S8

–

G-26, G-37

1-S23

1-S54

1-S54

–

1-S28

1-S52

G-26, G-37

1-S54

W1084427

1-S2

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

ENGINE

Symptom Probable Cause Solution

Deficient Output Incorrect injection timing Adjust injection

timing

Engine's moving parts seem to be seized Repair or replace

engine’s moving
parts

Uneven fuel injection Repair or replace

injection pump

Deficient nozzle injection Repair or replace

nozzle

Compression leak from cylinder Replace head

gasket, tighten
cylinder head screws,
glow plugs and
nozzle holders

Excessive Lubricant
Oil Consumption

Piston ring gap facing the same direction Shift ring gap

direction
Oil ring worn or stuck Replace oil ring 1-S28
Piston ring groove worn Replace piston 1-S28
Valve stem and valve guide worn Replace valve stem

and valve guide
Oil leaking due to defective seals or packing Replace defective

seals or packing

Fuel Mixed into
Lubricant Oil

Injection pump's plunge r worn Replace pump

element or injection

pump
Deficient nozzle injection Repair or replace

nozzle
Injection pump broken Replace injection

pump

Water Mixed into
Lubricant Oil

Head gasket defective Replace head gasket 1-S22
Cylinder block or cylinder head flawed Replace cylinder

block or cylinder

head

Reference
Page

1-S52

–

1-S52

1-S54

1-S21, S22

1-S27, S28

1-S33

–

1-S53

1-S54

1-S52

1-S22

W1088099

1-S3

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

ENGINE

Symptom Probable Cause Solution

Reference
Page

Low Oil Pressure Engine oil insufficient Replenish engine oil G-21

Oil strainer clogged Clean oil strainer G-35
Engine oil filter cartridge clogged Change engine oil

G-21

filter cartridge
Relief valve stuck with dirt Replace relief valve 1-S47
Relief valve spring weaken or broken Replace relief valve

–

spring
Excessive oil clearance of crankshaft bearing Replace main

1-S44
bearings, metals or
crankshaft

Excessive oil clearance of crankpin bearing Replace crankpin

1-S43
bearings

Excessive oil clearance of rocker arm Replace rocker arms,

1-S36
rocker arm brackets
or rocker arm shaft

Oil passage clogged Clean oil passage –
Different type of oil Use specified type of

–

oil

Oil pump defective Repair or replace oil

1-S47
pump

High Oil Pressure Different type of oil Use specified type of

–

oil

Relief valve defective Replace relief valve 1-S47

Engine Overheated Engine oil insufficient Replenish engine oil G-21

Fan belt broken or tensioned improperly Replace fan belt or

G-24
adjust fan belt
tension

Cooling water insufficient Replenish cooling

–

water

Radiator net and radiator fin clogged with dust Clean radiator net

–

and radiator fin

Inside of radiator corroded Clean inside of

G-37
radiator or replace
radiator

Cooling water flow route corroded Clean or replace

G-37
cooling water flow
route

Radiator cap defective Replace radiator cap 1-S50
Overload running Loosen load –
Head gasket defective Replace head gasket 1-S22
Incorrect injection timing Adjust injection

1-S52

timing

Unsuitable fuel used Use specified fuel –

W1090661

1-S4

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

2. SERVICING SPECIFICATIONS

[1] ENGINE BODY

Cylinder Head

Item Factory Specifications Allowable Limit

Cylinder Head Surface Flatness – 0.05 mm

0.0020 in.

Top Clearance 0.50 to 0.70 mm

0.0197 to 0.0276 in.

Compression Pressure 2.84 to 3.24 MPa

29.0 to 33.0 kgf/cm

2

412 to 469 psi

Variance Among Cylinders – 10 % or less

Valves

Valve Clearance (Cold) 0.145 to 0.185 mm

0.00571 to 0.00728 in.

Valve Seat Width 2.12 mm

0.0835 in.

Valve Seat Angle 0.79 rad

45°

Valve Face Angle 0.79 rad

45°

Valve Recessing −0.10 to 0.10 mm

−0.0039 to 0.0039 in.

Clearance between Valve Stem and Valve Guide

0.030 to 0.057 mm

0.00118 to 0.00224 in.

–

2.26 MPa

23.0 kgf/cm
327 psi

–

–

–

–

0.3 mm

0.0118 in.

0.10 mm

0.0039 in.

ENGINE

2

W1013874

Valve Stem O.D.

5.968 to 5.980 mm

0.23496 to 0.23543 in.

Valve Guide I.D.

6.010 to 6.025 mm

0.23661 to 0.23720 in.

Valve Spring

Free Length 31.3 to 31.8 mm

1.232 to 1.252 in.

Setting Load / Setting Length 64.7 N / 27.0 mm

6.6 kgf / 27.0 mm

14.6 lbs / 1.063 in.

28.4 mm

1.118 in.

54.9 N / 27.0 mm

5.6 kgf / 27.0 mm

12.3 lbs / 1.063 in.

Tilt – 1.2 mm

0.047 in.

–

–

W1014656

W1014987

1-S5

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

Rocker Arm

Item Factory Specifications Allowable Limit

Clearance between Rocker Arm Shaft and Rocker Arm

0.016 to 0.045 mm

0.00063 to 0.00177 in.

ENGINE

0.15 mm

0.0059 in.

Rocker Arm Shaft O.D.

10.473 to 10.484 mm

–

0.41232 to 0.41276 in.

Rocker Arm I.D.

10.500 to 10.518 mm

–

0.41339 to 0.41410 in.

Push Rod

Push Rod Alignment – 0.25 mm

0.0098 in.

Tappet

Clearance between Tappet and Guide Bore

Tappet O.D.

0.016 to 0.052 mm

0.00063 to 0.00205 in.

17.966 to 17.984 mm

0.10 mm

0.0039 in.
–

0.70732 to 0.70803 in.

Tappet Guide I.D.

18.000 to 18.018 mm

–

0.70866 to 0.70937 in.

Camshaft

Camshaft Side Clearance 0.15 to 0.31 mm

0.0059 to 0.0122 in.

0.50 mm

0.0197 in.

Camshaft Alignment – 0.01 mm

0.0004 in.

Cam Height of Intake and Exhaust 26.88 mm

1.0583 in.

Oil Clearance between Camshaft Journal and Cylinder Block
Bore

0.050 to 0.091 mm

0.00197 to 0.00358 in.

26.83 mm

1.0563 in.

0.15 mm

0.0059 in.

W1015094

W1015197

W1013874

Camshaft Journal O.D.

Cylinder Block Bore I.D.

1-S6

32.934 to 32.950 mm

1.29661 to 1.29724 in.

33.000 to 33.025 mm

1.29921 to 1.30020 in.

–

–

W1016577

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

Timing Gear

Timing Gear Backlash
Crank Gear- Idle Gear

ENGINE

Item Factory Specifications Allowable Limit

0.043 to 0.124 mm

0.00169 to 0.00488 in.

0.15 mm

0.0059 in.

Idle Gear-Cam Gear

0.047 to 0.123 mm

0.00185 to 0.00484 in.

Idle Gear-Injection Pump Gear

0.046 to 0.124 mm

0.00181 to 0.00488 in.

Crank Gear-Oil Pump Drive Gear

0.041 to 0.123 mm

0.00161 to 0.00484 in.

Clearance between Idle Gear Shaft and Idle Gear Bushing

0.020 to 0.084 mm

0.00079 to 0.00331 in.

Idle Gear Shaft O.D.

19.967 to 19.980 mm

0.78610 to 0.78661 in.

Idle Gear Bushing I.D.

20.000 to 20.051 mm

0.78740 to 0.78941 in.

Idle Gear Side Clearance 0.20 to 0.51 mm

0.0079 to 0.0201 in.

Piston • Piston Ring

Piston Pin Bore I.D. 20.000 to 20.013 mm

0.78740 to 0.78791 in.

Clearance between Piston Ring and Piston
Ring Groove

Second Ring 0.090 to 0.120 mm

0.00354 to 0.00472 in.

Oil Ring 0.04 to 0.08 mm

0.0016 to 0.0031 in.

Piston Ring Gap Top Ring 0.15 to 0.30 mm

0.0059 to 0.0118 in.

Second Ring 0.30 to 0.45 mm

0.0118 to 0.0177 in.

Oil Ring 0.15 to 0.30 mm

0.0059 to 0.0118 in.

0.15 mm

0.0059 in.

0.15 mm

0.0059 in.

0.15 mm

0.0059 in.

0.10 mm

0.0039 in.
–

–

0.80 mm

0.0315 in.

W1013874

20.05 mm

0.7894 in.

0.15 mm

0.0059 in.

0.15 mm

0.0059 in.

1.20 mm

0.0472 in.

1.20 mm

0.0472 in.

1.20 mm

0.0472 in.

W1016812

Connecting Rod

Connecting Rod Alignment – 0.05 mm

0.0020 in.

Clearance between Piston Pin and Small End Bushing

Piston Pin O.D.

0.014 to 0.038 mm

0.00055 to 0.00150 in.

20.002 to 20.011 mm

0.10 mm

0.0039 in.
–

0.78748 to 0.78783 in.

Small End Bushing I.D.

20.025 to 20.040 mm

0.78839 to 0.78897 in.

–

W1016985

1-S7

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

Crankshaft

Item Factory Specifications Allowable Limit

Crankshaft Alignment – 0.02 mm

0.0008 in.

Crankshaft Side Clearance 0.15 to 0.31 mm

0.0059 to 0.0122 in.

Oil Clearance between Crankshaft Journal and Crankshaft
Bearing 1

0.034 to 0.106 mm

0.00134 to 0.00417 in.

0.50 mm

0.0197 in.

0.20 mm

0.0079 in.

ENGINE

Crankshaft Journal O.D.

Crankshaft Bearing 1 I.D.

Oil Clearance between Crankshaft Journal and Crankshaft
Bearing 2 (Flywheel Side)

Crankshaft Journal O.D.
Crankshaft Bearing 2 I.D.

Oil Clearance between Crankshaft Journal and Crankshaft
Bearing 3 (Intermediate)

Crankshaft Journal O.D.

Crank bearing 3 I.D.

Oil Clearance between Crankpin and Crankpin Bearing

39.934 to 39.950 mm

1.57221 to 1.57284 in.

39.984 to 40.040 mm

1.57417 to 1.57638 in.

0.028 to 0.059 mm

0.00110 to 0.00232 in.

43.934 to 43.950 mm

1.72969 to 1.73032 in.

43.978 to 43.993 mm

1.73142 to 1.73201 in.

0.028 to 0.059 mm

0.00110 to 0.00232 in.

39.934 to 39.950 mm

1.57221 to 1.57284 in.

39.978 to 39.993 mm

1.57394 to 1.57453 in.

0.020 to 0.051 mm

0.00079 to 0.00201 in.

–

–

0.20 mm

0.0079 in.
–

–

0.20 mm

0.0079 in.
–

–

0.15 mm

0.0059 in.

Crankpin O.D.

Crankpin Bearing I.D.

Cylinder Liner

Cylinder Liner I.D.
[Standard]

Oversized Cylinder Liner I.D.
[Oversize : 0.25 mm (0.0098 in.)]

33.959 to 33.975 mm

1.33697 to 1.33760 in.

33.995 to 34.010 mm

1.33839 to 1.33898 in.

67.000 to 67.019 mm

2.63779 to 2.63854 in.

67.250 to 67.269 mm

2.64764 to 2.64839 in.

–

–

W1017094

67.169 mm

2.64445 in.

67.419 mm

2.65429 in.

W1017278

1-S8

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

[2] LUBRICATING SYSTEM

Oil Pump

Item Factory Specifications Allowable Limit

Engine Oil Pressure
At Idle Speed

49 kPa

0.5 kgf/cm
7 psi

ENGINE

–

2

At Rated Speed

196 to 441 kPa

2.0 to 4.5 kgf/cm
28 to 64 psi

Clearance between Inner Rotor and Outer Rotor 0.03 to 0.14 mm

0.0012 to 0.0055 in.

Clearance between Outer Rotor and Pump Body 0.07 to 0.15 mm

0.0028 to 0.0059 in.

End Clearance between Inner Rotor and Cover 0.075 to 0.135 mm

0.00295 to 0.00531 in.

[3] COOLING SYSTEM

Thermostat

Thermostat's Valve Opening Temperature 69.5 to 72.5 °C

157.1 to 162.5 °F

Temperature at which Thermostat Completely Opens 85 °C

185 °F

Radiator

Radiator Water Tightness Water tightness at

specified pressure

157 kPa

2

1.6 kgf/cm

Radiator Cap Air Leakage 10 seconds or more

88 → 59 kPa

0.9 → 0.6 kgf/cm
13 → 9 psi

Fan Belt Tension 7.0 to 9.0 mm / 98 N

0.28 to 0.35 in. / 98 N
(10 kgf, 22 lbs)

, 23 psi

2

147 kPa

1.5 kgf/cm

2

21 psi

–

–

–

W1017384

–

–

W1017547

–

–

2

–

W1013874

1-S9

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

[4] FUEL SYSTEM

Injection Pump

Item Factory Specifications Allowable Limit

Injection Timing 0.28 to 0.31 rad (16° to

18°) Before T.D.C.

Fuel Tightness of Pump Element – 13.73 MPa

Fuel Tightness of Delivery Valve 10 seconds

13.73 → 12.75 MPa
140 →130 kgf/cm

1991 → 1849 psi

2

13.73 → 12.75

140 →130 kgf/cm

1991 → 1849 psi

Injection Nozzle

Fuel Injection Pressure 13.73 to 14.71 MPa

140 to 150 kgf/cm

2

1991 to 2134 psi

Fuel Tightness of Nozzle Valve Seat When the pressure is

12.75 MPa

(130 kgf/cm

2

, 1849 psi),

the valve seat must be

fueltight

–

140 kgf/cm

1991 psi

5 seconds

MPa

–

–

ENGINE

2

2

W1013874

W1013973

1-S10

G21LD · G21HD, WSM

NOTEn

KiSC issued 08, 2007 A

ENGINE

3. TIGHTENING TORQUES

Tightening torques of screws, bolts and nuts on the table below are especially specified.

(For general use screws, bolts and nuts : See page G-8.)

Item Size x Pitch N·m kgf·m ft-lbs

Starter M terminal nut M6 × 1.0 9.8 to 13.7 1.0 to 1.4 7.2 to 10.1
Alternator B terminal nut M6 × 1.0 7.8 to 9.3 0.80 to 0.95 5.8 to 6.9
Glow plug terminal mounting nut 1.0 to 1.8 0.10 to 0.18 0.74 to 1.33
Universal joint mounting scre w M8 × 1.25 23.5 to 27.5 2.4 to 2.8 17.4 to 20.3
Engine mounting nut M8 × 1.25 23.5 to 27.5 2.4 to 2.8 17.4 to 20.3
Cylinder head screw M8 × 1.25 37.3 to 42.2 3.8 to 4.3 27.5 to 31.1
* Cylinder head cover cap nut M6 × 1.0 3.9 to 5.9 0.4 to 0.6 2.9 to 4.3
Injection pipe retaining nut M12 × 1.5 24.5 to 34.3 2.5 to 3.5 18.1 to 25.3
Nozzle holder assembly M20 × 1.5 49.0 to 68.6 5.0 to 7.0 36.2 to 50.6
Overflow pipe assembly retaining nut M12 × 1.5 19.6 to 24.5 2.0 to 2.5 14.5 to 18.1
Glow plug M8 × 1.0 7.85 to 14.7 0.8 to 1.5 5.8 to 10.8
* Rocker arm bracket nut M6 × 1.0 9.8 to 11.3 1.00 to 1.15 7.2 to 8.3
* Fan drive pulley retaining screw M12 × 1.5 117.7 to 127.5 12.0 to 13.0 86.8 to 94.0
* Idle gear shaft mounting screw M6 × 1.0 9.8 to 11.3 1.00 to 1.15 7.2 to 8.3
* Connecting rod screw M7 × 0.75 26.5 to 30.4 2.7 to 3.1 19.5 to 22.4
* Flywheel bolt M10 × 1.25 53.9 to 58.8 5.5 to 6.0 39.8 to 43.4
* Main bearing case screw 2 M7 × 1.0 26.5 to 30.4 2.7 to 3.1 19.5 to 22.4
* Main bearing case screw 1 M6 × 1.0 12.7 to 15.7 1.3 to 1.6 9.4 to 11.6
Oil pressure switch PT 1/8 14.7 to 19.6 1.5 to 2.0 10.8 to 14.5
Nozzle holder 34.3 to 39.2 3.5 to 4.0 25.3 to 28.9

• For * marked screws, bolts and nuts on the table, apply engine oil to their threads and seats before
tightening.

• The letter “M” in Size x Pitch means that the screw, bolt or nut dimension stands for metric. The size is
the nominal outside diameter in mm of the threads. The pitch is the nominal distance in mm between two
threads.

W1013236

1-S11

G21LD · G21HD, WSM

n

KiSC issued 08, 2007 A

4. CHECKING, DISASSEMBLING AND SERVICING

[1] SEPARATING ENGINE

(1) Disassembling and Assembling

Dismount Mower

1. See “MOWER” section.

Draining Engine Oil

1. Park the machine on level ground.

2. Start and warm up the engine for approx. 5 minutes.

3. Place an oil pan underneath the engine.

4. Remove the drain plug (1) to drain oil.

5. After draining, screw in the drain plug (1).

(When refilling)

• Fill the engine oil up to the upper line on the dipstick (3).

2.8 L

Engine oil Capacity

IMPORTANT

• Never mix two different type of oil.

• Use the proper SAE Engine Oil according to ambient
temperatures.
Refer to "LUBRICANTS, FUEL AND COOLING WATER".(See
page G-7.)

(1) Drain Plug
(2) Oil Inlet Plug
(3) Dipstick

(A) Upper Level
(B) Lower Level

2.95 U.S.qts.

2.4 lmp.qts.

ENGINE

W1019171

W1019220

1-S12

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

ENGINE

Draining Coolant

CAUTION

• Never open the radiator cap while operating or immediately
after stopping. Otherwise, hot water will spout out from the
radiator. Wait for more than ten minutes to cool the radiator,
before opening the cap.

1. Stop the engine and let cool down.

2. Remov e the radiator coolant drain plug (3) and engine coolan t
drain plug (4) to drain the coolant.

3. Remove the radiator cap (1) to completely drain the coolant.

4. After all coolant is drained, close the drain plugs.

Radiator

Coolant Capacity

Recovery tank

2.1 L

2.2 U.S.qts.

1.8 lmp.qts.

0.25 L

0.26 U.S.qts.

0.22 lmp.qts

(1) Radiator Cap
(2) Recovery Tank

(3) Radiator Coolant Drain Plug
(4) Engine Coolant Drain Plug

W1019510

Battery

CAUTION

• When disconnecting the battery cables, disconnect the
negative cable from the battery first. When connecting,
connect the positive cable to the battery first.

1. Disconnect the negative cable (1) from the battery.

2. Disconnect the positive cable (2) from the battery.

(1) Negative Cable (2) Positive Cable

W1019788

Bonnet and Air Cleaner

1. Disconnect the 1P connectors (3) from the head light (2).

2. Remove the wiring (4) from the bonnet.

3. Remove the bonnet stay mounting screws (6).

4. Remove the bonnet with the bonnet bracket (5) from the frame.

5. Loosen the air cleaner hose clamp.

6. Remove the air cleaner (1) with air cleaner hose.

(1) Air Cleaner
(2) Head Light
(3) 1P Connectors

(4) Wiring
(5) Bonnet Bracket
(6) Bonnet Stay Mounting Screws

W1019921

1-S13

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

ENGINE

Wiring

1. D isconnect the tie (1) from the alterna tor, and remove the P TO
cable (3) and wiring (2).

2. Disconnect 2P connector (5) and wiring (4) from the alternator.

3. Disconnect 1P connector (8) from the oil pressure switch.

4. Disconnect 1P connector (10) and wiring (9) from the starter.

5. Disconnect the tie (6) from the rear end plate.

6. Disconnect the ground cable (7).

9.8 to 13.7 N·m

Starter M terminal nut

Tightening torque

Alternator B terminal nut

1.0 to 1.4 Kgf·m

7.2 to 10.1 ft-lbs

7.8 to 9.3 N·m

0.80 to 0.95 Kgf·m

5.8 to 6.9 ft-lbs

(1) Tie
(2) Wiring
(3) PTO Cable
(4) Wiring
(5) 2P Connector

(6) Tie
(7) Ground Cable
(8) 1P Connector
(9) Wiring

(10) 1P Connector

W1020275

Front Cover and PTO Assembly

1. Remove the front PTO cover.

2. R emove the PTO clutch s pring (4), brake spring ( 7) and return
spring (6).

3. Remove the belt stay (9).

4. Remove the pulley (10).

5. Remove the front PTO belts (8).

6. Remove the cotter pin and flange bolt (3).

7. Pull out the PTO brake assembly (5) and tension arm (2) with
tension pulley.

(When reassembling)

• Apply grease to the tension arm bushings a nd the PTO brake
bushing.

• After reassembl ing the PTO cl utch spring, be s ure to adju st the
front PTO belt tension. (See page 7-S3)

• After reassembling the belt stay, be sure to adjust the clearance
between the belt stay and front PTO belt. (See page 7-S3)
Clearance (L) :1.0 to 2.5 mm (0.04 to 0.10 in.)

(1) Cotter Pin
(2) Tension Arm
(3) Flange Bolt
(4) PTO Clutch Spring
(5) PTO Brake Assembly

(6) Return Spring
(7) Brake Spring
(8) Front PTO Belts
(9) Belt Stay

(10) Pulley

W1020759

1-S14

G21LD · G21HD, WSM

IMPORTANTn

KiSC issued 08, 2007 A

ENGINE

Muffler, Wiring, Accelerator and Hose

1. Remove the muffler mounting screws (1), (7).

2. Remove the muffler (2).

3. Disconnect 1P connector (5) from the coolant temperature
sensor.

4. Disconnect the wiring (3) from the glow plug.

5. Disconnect 1P connector (4) from the engine stop solenoid.

6. Disconnect the accelerator wire (6).

7. Loosen the hose clamps.

8. Remove the return hose 1 (8) and fuel hose 1 (9).

9. Disconnect the ground cables (10), (11).

• When disconnecting the fuel hose 1 and return hose 1, be
careful not to let the fuel spill out of the hoses.

(When reassembling)

1.0 to 1.8 N·m

0.10 to 0.18 Kgf·m

0.74 to 1.33 ft-lbs

Tightening torque

Glow plug terminal
mounting nut

(1) Muffler Mounting Screws
(2) Muffler
(3) Wiring
(4) 1P Connector
(5) 1P Connector
(6) Accelerator Wire

(7) Muffler Mounting Screw
(8) Return Hose 1

(9) Fuel Hose 1
(10) Ground Cable
(11) Ground Cable

W1021263

Universal Joint*****

1. Remove the universal joint mounting screws (1).

2. Disconnect the universal joint (2) from the fun drive pulley.

(When reassembling)

• Apply grease to the all splines on the drive shaft.

Tightening torque

(1) Universal Joint Mounting Screw (2) Universal Joint

Univer s al joint
mounting screw

23.5 to 27.5 N·m

2.4 to 2.8 Kgf·m

17.4 to 20.3 ft-lbs

W1021776

1-S15

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

ENGINE

Separating Engine

1. Pull out the hairpin cotters from the radiator.

2. R emove the e ngine mount ing n uts, a nd s upport th e eng ine with
an engine lift hook and hoist.

3. Separate the engine with the radiator from the frame, taking care
not to damage the radiator.

(When reassembling)

• Fit the radiator to the frame, adjusting the clearance between the
radiator and the fan as shown in the figure.

23.5 to 27.5 N·m

Tightening torque Engine mounting nut

2.4 to 2.8 Kgf·m

17.4 to 20.3 ft-lbs

(Reference)

9.0 mm

0.35 in.

2.0 mm

0.08 in.

Clearance between fan
and radiator

Factory
spec.

L

H

(1) Fan
(2) Radiator

L : Circumferential clearance

between fan and radiator

H : Longitudinal clearance between

fan and radiator

W1021955

1-S16

G21LD · G21HD, WSM

NOTEn

KiSC issued 08, 2007 A

[2] ENGINE BODY

(1) Checking and Adjusting

ENGINE

Compression Pressure

1. Run the engine until it is warmed up.

2. Stop the engine.

3. Disconnect the 2P connector from the fuel pump.

4. Remove the air cleaner, the muffler and all injection nozzles.

5. Disconnect the accelerator wire.

6. Remove the air cleaner stay.

7. Remove the glow plugs and return hose 1.

8. Engage the parking brake.

9. Set a compression tester (Code No. 07909-30208) with the
adaptor (Adaptor H, Code No. 07909-31231) to the nozzle hole.

10.While cranking the engine with the starter, measure the
compression pressure.

11.Repeat steps 9 and 10 for each cylinder.

12.If the measurem ent is below the allowable limit, apply a small
amount of oil to the cylinder wall through the nozzle hole and
measure the compression pressure again.

13.If the compres sion pressure is still less than the allowabl e limit,
check the top clearance, valve and cylinder head.

14.If the c ompression pressu re increases after a pplying oil, check
the cylinder wall and piston rings.

• Check the compression pressure with the specified valve
clearance.

• Always use a fully charged battery for performing this test.

• Variances in cylinder compression values should be under
10 %.

Compression pressure

Factory spec.

Allowable limit

2.84 to 3.24 MPa

29.0 to 33.0 kgf/cm
412 to 469 psi

2.26 MPa

23.0 kgf/cm
327 psi

2

2

W1022478

1-S17

G21LD · G21HD, WSM

NOTEn

KiSC issued 08, 2007 A

ENGINE

Top Clearance

1. Remove the cylinder head (Do not attempt to remove the cylinder
head gasket completely).

2. B ring the pis ton to its top dead cente r fasten 1 .5 mm dia. 5 to 7
mm long fuse wires to 3 to 4 sp ots on the piston top wi th gr ease
so as to avoid the intake and exhaust valves and the combustion
chamber ports.

3. B ring the pisto n to its middle position, insta ll the cylinde r head,
and tighten the cylinder head screws to specification. (Head
gasket must be changed to new one.)

4. Turn the crank shaft until the piston exceeds its top dead center.

5. Remove the cylinder head, and measure the thickness of the
squeezed fuses.

6. If the measurement is not within the factory specifications, check
the oil clearanc e of between the crankpin and crankpin bea ring
and between the piston pin and small end bushing.

• After checking the t op clearance, be sure to assemble the
cylinder head with a new cylinder head gasket.

Top clearance Factory spec.

0.50 to 0.70 mm

0.0197 to 0.0276 in.

Tightening torque Cy linder head screw

(1) Fuse

37.3 to 42.2 N·m

3.8 to 4.3 kgf·m

27.5 to 31.1 ft-lbs

W10107670

1-S18

G21LD · G21HD, WSM

IMPORTANTn

NOTEn

KiSC issued 08, 2007 A

ENGINE

Valve Clearance

• The valve clearance must be checked and adjusted when
engine is cold.

1. Remove the cylinder head cover and the glow plugs.

2. Align the “1TC” mark (1) on the flywheel and alignment mark (2)
on the rear end plate so that the No. 1 piston comes to the
compression top dead center.

3. Check the following valve clearance marked with “I” using a
feeler gauge.

[When No. 1 piston comes to the compression top dead center]

Cylinder No. No.1 No.2 No.3
Intake valve HH
Exhaust valve HH

4. If the clearance is not within the factory specifications, adjust with
the adjusting screw.

5. Then turn the flywheel 6.28 rad (360°), and align the “1TC” mark
(1) on the flywheel and alig nment mark (2) on the rear end plate
so that the No.1 piston comes to the overlap position.

6. Check the following valve clearance marked with “I” using a
feeler gauge.

[When No. 1 piston comes to the overlap position]

Cylinder No. No.1 No.2 No.3
Intake valve I
Exhaust valve I

7. If the clearance is not within the factory specifications, adjust with
the adjusting screw.

Intake and exhaust
valve clearance (Cold)

Factory spec.

0.145 to 0.185 mm

0.00571 to 0.00728 in.

• The sequence of cylinder numbers is given as No.1, No.2
and No.3 starting from the gear case side.

• After adjusting the valve clearance, secure the adjusting
screw with the lock nut.

(1) “1TC” Mark
(2) Alignment Mark

A : Gear Case Side

W10113200

1-S19

G21LD · G21HD, WSM

IMPORTANTn

KiSC issued 08, 2007 A

(2) Disassembling and Assembling
(A) Cylinder Head and Valves

ENGINE

External Components

1. Remove the air cleaner stay (5).

2. R emove the water pipe 1 (2), water pipe 2 ( 7) and radiator (8)
with the recovery tank.

3. R emo ve the alt ernato r (9) and fan belt (10).

4. R e mo ve the cooli ng fan (4) and fan pul ley .

5. Remove the starter (11).

6. Remove the engine stop solenoid (1).

7. Remove the engine mounting stays (6).

8. Remove the PTO pulley.

(When reassembling)

• Connect the water pipe 1 with the white marking facing upward.

• Connect the water pipe 2 with the yellow marking facing upward.

• Install the engine stop solenoid so that the plunger moves
smoothly.

• After reassembling the fan belt, be sure to adjust the fan belt
tension. (See page 1-S49)

(1) Engine Stop Solenoid
(2) Water Pipe 1
(3) PTO Pulley
(4) Cooling Fan
(5) Air Cleaner Stay
(6) Engine Mounting Stay

(7) Water Pipe 2
(8) Radiator

(9) Alternator
(10) Fan Belt
(11) Starter

W1024919

Cylinder Head Cover

1. Remove the head cover cap nuts.

2. Remove the cylinder head cover.

(When reassembling)

• Check to see if the cylinder head cover gasket is not defective.

• Apply engine oil to the cylinder head cover cap nuts.
And tighten them.

3.9 to 5.9 N·m

0.4 to 0.6 kgf·m

2.9 to 4.3 ft-lbs
W10147380

Tightening torque

Cylinder head cover cap
nut

Injection Pipes

1. Loosen the screws on the pipe clamps (1).

2. Detach the injection pipes (2).

(When reassembling)

• Blow out dust from the pipes with compressed air.
Then reassemble the pipes in the reverse order..

Tightening torque

Injection pipe retaining
nut

24.5 to 34.3 N·m

2.5 to 3.5 kgf·m

18.1 to 25.3 ft-lbs

(1) Pipe Clamp (2) Injection Pipe

W10150780

1-S20

G21LD · G21HD, WSM

n

IMPORTANTn

KiSC issued 08, 2007 A

ENGINE

Nozzle Holder Assembly and Glow Plug

1. Remove the overflow pipe assembly (5).

2. Remov e the nozzle holde r assemblies (2) us ing a 21 mm deep
socket wrench.

3. Remove the copper gasket and heat seal (3).

4. Remove the lead (4) from the glow plugs.

5. Remove the glow plugs (1).

(When reassembling)

• Replace the copper gasket and heat seal with new one.

49.0 to 68.6 N·m

Tightening torque

Nozzle holder assembly

Overflow pipe assembly
retaining nut

Glow plug

5.0 to 7.0 kgf·m

36.2 to 50.6 ft-lbs

19.6 to 24.5 N·m

2.0 to 2.5 kgf·m

14.5 to 18.1 ft-lbs

7.85 to 14.7 N·m

0.8 to 1.5 kgf·m

5.8 to 10.8 ft-lbs

(1) Glow Plug
(2) Nozzle Holder Assembly
(3) Heat Seal

(4) Lead
(5) Overflow Pipe Assembly

W10259700

Removal Procedure for Nozzle Heat Seal Service

IMPORTANT

• Use a plus (phillips head) screw driver (1) that has a Dia.
bigger than the heat seal hole (Approx. 6 mm) 1/4 in..

1. Drive a screw driver (1) lightly into the heat seal hole.

2. Turn a screw driver three or four times each way.

3. Whil e turning the screw driver, slo wly pull the heat seal (4) out
together with the copper gasket (3).

4. If the heat seal drops, repeat the above procedure.

(1) Screw driver (Plus)
(2) Nozzle Holder

(3) Copper Gasket
(4) Heat Seal

W10154410

Rocker Arm and Push Rod

1. Remove the rocker arm bracket nuts.

2. Detach the rocker arm assembly (1).

3. Remove the push rods (2).

(When reassembling)

• When putting the push rods (2) onto the tappets (3), check to see
if their ends are properly engaged with the grooves.

• After installing the rocker arm, be sure to a djust the valve
clearance.

• Apply engine oil to the rocker arm bracket nuts.
And tighten them.

Tightening torque Rocker arm bracket nut

(1) Rocker Arm Assembly
(2) Push Rod

(3) Tappet

9.8 to 11.3 N·m

1.00 to 1.15 kgf·m

7.2 to 8.3 ft-lbs

W10155810

1-S21

G21LD · G21HD, WSM

NOTEn

IMPORTANTn

IMPORTANTn

KiSC issued 08, 2007 A

ENGINE

Cylinder Head

1. Loosen the pipe clamp, and remove the water return pipe.

2. Remove the cylinder head bolt in the order of (14) to (1).

3. Lift up the cylinder head to detach.

4. Remove the cylinder head gasket and O-ring.

(When reassembling)

• Replace the cylinder head gasket with a new one.

• Securely fit the O-ring to the pipe pin.

• Tighten the cylinder head bolts after applying sufficient oil.

• Tighten the cylinder head bolts in diagonal sequence starting
from the center. (Refer to figure left.)

• Tighen them unifo rmly, or the cylinder head m ay deform in the
long run.

• Retighten the cy linde r head bol ts after r un nin g the eng ine for 30
minutes.

• To Loosen : 14 to 1

• To Tighten : 1 to 14

37.3 to 42.2 N·m

Tightening torque Cylinder head screw

3.8 to 4.3 kgf·m

28.0 to 31.1 ft-lbs
W10159710

Tappets

1. Remove the tappets (1) from the crankcase.

(When reassembling)

• Before installing the tappets, apply engine oil thinly around them.

• Mark the cylinder number to the tappets to prevent
interchanging.

(1) Tappet

W1027457

Valves

1. Remove the valve caps (2).

2. Remove the valve spring collet (3), pushing the valve spring
retainer (4) by valve spring replacer (1).

3. R emo ve the v alve spring re tain er (4), v alve sp ring ( 5) and v alve
stem seal (6).

4. Remove the valve (7).

(When reassembling)

• Wash the va lve s tem and valve guid e hole, and apply eng ine oi l
sufficiently.

• After installing the valve spring collets, lightly tap the stem to
assure proper fit with a plastic hammer.

• Don’t cha nge the combination of valve and valve guide.

(1) Valve Spring Replacer
(2) Valve Cap
(3) Valve Spring Collet
(4) Valve Spring Retainer

(5) Valve Spring
(6) Valve Stem Seal
(7) Valve

W10162820

1-S22

G21LD · G21HD, WSM

NOTEn

KiSC issued 08, 2007 A

(B) Timing Gears and Camshaft

ENGINE

Injection Pump and Speed Control Plate

1. Remove the socket head screws and nuts, and remove the
injection pump (3).

2. Remove the screws and separate the speed control plate (2),
taking care not to damage the spring (4).

3. Disconnect the spring (4) and remove the speed control plate (2).

(When reassembling)

• Hook the spring (4) to the lever (5) first and install the speed
control plate (2).

• Be sure to place the copper washers underneath two screws (1)
(as shown in the figure).

• Position the slot (9) on the fork lever just under the slot (8) on the
crankcase.

• Insert the injection pump (3) so that the control rod (7) should be
pushed by the spring (6) at its end and the pin (10) on the rod
engages with the slot (9) on the fork lever (as shown in the
figure).

• The sealant is applied to both sides of the soft metal gasket
shim. The liquid gasket is not required for assembling.

• Addition or reduction of shim (0.05 mm, 0.0020 in.) delays or
advances the injection timing by approx. 0.0087 rad (0.5°).

• In disassembling and replacing, be sure to use the same
number of new gasket shims with the same thickness.

(1) Screws and Copper Washers
(2) Speed Control Plate
(3) Injection Pump
(4) Spring
(5) Lever

(6) Spring
(7) Control Rod
(8) Slot (Crankcase Side)
(9) Slot (Fork Lever Side)

(10) Pin

W10167080

Fan Drive Pulley

1. Set the stopper to the flywheel.

2. Remove the fan drive pulley retaining screw.

3. Draw out the fan drive pulley with a puller.

(When reassembling)

• Install the pulley to the crankshaft, aligning the mark (1) on them.

• Apply engine oil to the fan drive pulley retaining screws, and
tighten them.

Tightening torque

(1) Aligning Mark

Fan drive pulley retaining
screw

117.7 to 127.5 N·m

12.0 to 13.0 kgf·m

86.8 to 94.0 ft-lbs

W10172470

1-S23

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

ENGINE

Gear Case

1. Remove the screw (1).

2. Disconnect the start spring (2) in the speed control plate
mounting hole.

3. Remove the gear case (3).

(When reassembling)

• Apply a liquid gas ket (Three Bond 1215 or equivalent) to both
sides of the gear case gasket (4).

• Be sure to set three O-rings (5) inside the gear case.

(1) Screw
(2) Start Spring
(3) Gear Case

(4) Gear Case Gasket
(5) O-rings

W10174840

Idle Gear

1. Remove the external snap ring (3), the collar (2) and the idle gear
(1).

2. Remove the idle gear shaft mounting screws.

3. Remove the idle gear shaft.

(When reassembling)

• Install the idl e gear, aligning th e mark on the gears r eferring to
the figure.

• Apply engine oil to the idle gear shaft mounting screws.
And tighten them.

Tightening torque

(1) Idle Gear
(2) Idle Gear Collar

Idle gear shaft mounting
screw

(3) External Snap Ring

9.8 to 11.3 N·m

1.00 to 1.15 kgf·m

7.2 to 8.3 ft-lbs

W1028418

1-S24

G21LD · G21HD, WSM

KiSC issued 08, 2007 A

ENGINE

Fuel Camshaft

1. Remove the retaining plate (1).

2. Remove the fork lever holder mounting screws (8), then draw out
the injection pump gear (3) and fuel camshaft (2) with the
governor fork assembly.

(When reassembling)

• Hook the gevernor spring (7) to the fork lever 2 (6) as shown in
the figure before installing the fork lever assembly to the
crankcase.

(1) Retaining Plate
(2) Fuel Camshaft
(3) Injection Pump Gear
(4) Governor Sleeve

(5) Fork Lever 1
(6) Fork Lever 2
(7) Governor Spring
(8) Fork Lever Holder Mounting Screw

W10178820

Oil Pump and Crankshaft Gear

1. Remove the oil pump gear (6).

2. Remove the oil pump (5).

3. Remove the collar (4), O-ring (3) and oil slinger (2).

4. Remove the crankshaft gear (1) with a puller.

(When reassembling)

• Install the coll ar after align ing the mar ks on the gear s. (See the
figure at “Idle Gear”.)

(1) Crankshaft Gear
(2) Crankshaft Oil Slinger
(3) O-ring

(4) Crankshaft Collar
(5) Oil Pump
(6) Oil Pump Gear

W10180290

1-S25

G21LD · G21HD, WSM

IMPORTANTn

KiSC issued 08, 2007 A

(C) Connecting Rod and Piston

ENGINE

Oil Pan and Oil Strainer

1. Remove the oil pan (4).

2. Remove the oil strainer (3).

(When reassembling)

• Install the oil strainer, using care not to damage the O-ring (1).

• Using the hole (6) numbered “3”, install the oil strainer by
mounting screw.

• Apply liquid gask et (Three Bo nd 1270D or 1270C) to the oil pan
as shown in the figure.

• Scrape off the old adhesive completely. Wipe th e sealing
surface clean using waste cloth soaked with gasoline.
Now apply n e w a d he si v e 3 to 5 mm (0.1 2 t o 0. 2 0 in .) t hi c k a l l
over the contact surfac e. Apply the adhesive also on the
center of the flange as w ell as on th e inner wa ll of ea ch b olt
hole.

• Cut the nozzle of t he “flu id seala nt” c ontain er at it s sec ond
notch. Apply “fluid sealant” about 5 mm (0.20 in.) thick.
Within 20 minutes after the application of fluid sealant,
reassemble the components. Wait then for about 30
minutes, and pour oil in the crankcase.

(1) O-ring
(2) Screw
(3) Oil Strainer
(4) Oil Pan

(5) Oil Pan Mounting Screws
(6) Hole
(7) Fluid Sealant

W10265670

Connecting Rod Cap

1. Remove the connecting rod screws from connecting rod cap.

2. R e mo ve the conne cti ng ro d caps.

(When reassembling)

• Align the marks (a) with each other. ( Face th e m ar ks to ward the
injection pump.)

• Apply engine oil to the connecting rod screws and lightly screw it
in by hand, then tighten it to the specified torque.
If the connecting rod scr ew wo n’t b e s crew ed i n s moo thly, c lean
the threads.
If the connecting rod screw is still hard to screw in, replace it.

• Do not change the combination of crankpin bearing and
connecting rod.

Tightening torque Connecting rod screw

(a) Mark

26.5 to 30.4 N·m

2.7 to 3.1 kgf·m

19.5 to 22.4 ft-lbs

W10275480

1-S26

G21LD · G21HD, WSM

IMPORTANTn

KiSC issued 08, 2007 A

ENGINE

Piston

1. Turn the flywheel and bring the piston to top dead center.

2. Draw out the piston up ward by ligh tly tappin g it from the bo ttom
of the crankcase with the grip of a hammer.

3. Draw out the other pistons after the same method as above.

(When reassembling)

• Before inserting the piston into the cylinder, apply enough engine
oil to the cylinder.

• When inserting the pis ton into the cylinde r, f ace the mark on the
connecting rod to the injection pump.

• Do not change the combination of cylinder and piston. Make
sure of the position of each piston by marking. For example,
mark “1” for piston No. 1.

• When installing the piston into the cylinder, place the gaps
of all of the piston rings as shown in the figure.

• Carefully insert the piston using a piston ring compressor.
Otherwise, their chrome-plated section may be scratched,
causing trouble inside the cylinder.

(A) Top Ring Gap
(B) Second Ring Gap
(C) Oil Ring Gap
(D) Piston Pin Hole

(a) 0.785 rad (45°)
(b) 0.785 rad (45°)
(c) 0.785 rad (45°)
(d) Mark

W10277450

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G21LD · G21HD, WSM

IMPORTANTn

KiSC issued 08, 2007 A

ENGINE

Piston Ring and Connecting Rod

1. Remove the piston rings using a piston ring tool (Code No.
07909-32121).

2. R emove the piston pin (7 ), and separat e the connec ting rod (6 )
from the piston (5).

(When reassembling)

• When installing the rings, assemble the rings so that the
manufacturer’s mark (12) near the gap faces the top of the piston.

• When installi ng the oil ring o nto the piston, plac e the expander
joint (10) on the opposite side of the oil ring gap (11).

• Apply engine oil to the piston pin.

• When installing the connecting rod to the piston, immerse the
piston in 80 °C (176°F) oi l for 10 to 15 minutes and insert the
piston pin to the piston.

• When installi ng the connecti ng rod to the piston, align th e mark
(8) on the connecting rod to the fan-shaped concave (9).

• Mark the same number on the connecting rod and the piston
so as not to change the combination.

(1) Top Ring
(2) Second Ring
(3) Oil Ring
(4) Piston Pin Snap Ring
(5) Piston
(6) Connecting Rod

(7) Piston Pin
(8) Mark

(9) Fan-Shaped Concave
(10) Expander Joint
(11) Oil Ring Gap
(12) Manufact urer’s Mark

W10281670

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