Kubota WG1903-G-E3 User manual

WG1605
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WG1605
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L
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WG1605
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GL
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WG1605
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WG1605
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LN
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WG1903
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WG1903
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WG1903
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WG1903
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WG1903
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WG2503
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WG2503
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WG2503
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WG2503
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WG2503
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WG3800
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WG3800
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WG3800
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WG3800
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WG3800
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PRINTED IN JAPAN
© KUBOTA Corporation 2011
U.S.A. :KUBOTAENGINEAMERICACORPORATION
505 SchelterRoad,Lincolnshire,Illinois 60069 U.S.A.
Telephone:(
847 ) 955 - 2500
Canada :KUBOTACANADALTD.
5900  14 thAvenue,Markham,Ontario,L 3 S 4 K 4 ,Canada
Telephone:(
905 ) 294 - 7477
France :KUBOTAEUROPES.A.S
19 - 25 ,RueJulesVercruysse,Z.I.BP 88 , 95101 ArɡenteuilCedex,France
Telephone:(
33 ) 1 - 3426 - 3434
Italy :KUBOTAEUROPES.A.SItalyBranch
ViaGrandi,
29  20068 PeschieraBorrome(MI)Italy
Telephone:(
39 ) 02 - 51650377
Germany :KUBOTA(DEUTSCHLAND)GmbH
SenefelderStr.
3 - 5  63110 Rodɡau/Nieder-Roden,Germany
Telephone:(
49 ) 6106 - 873 - 0
U.K. :KUBOTA(U.K.)LTD.
DormerRoad,Thame,Oxfordshire,OX
9  3 UN,U.K.
Telephone:(
44 ) 1844 - 214500
Australia :KUBOTAAUSTRALIAPTYLTD.
25 - 29 PermasWay,Truɡanina,VIC 3029 ,Australia
Telephone:(
61 )- 3 - 9394 - 4400
Malaysia :SIMEKUBOTASDN.BHD.
No.
3 JalanSepadu 25 / 123 TamanPerindustrianAxis,
Seksyen
25 , 40400 ShahAlam,SelanɡorDarulEhsanMalaysia
Telephone:(
60 ) 3 - 736 - 1388
Philippines :KUBOTAPHILIPPINES,INC.
232 QuirinoHiɡhway,Baesa,QuezonCity 1106 ,Philippines
Telephone:(
63 ) 2 - 422 - 3500
Indonesia :P.T.KUBOTAINDONESIA
TamanIndustriBukitSemaranɡBaru(BSB)BlokD.
1 Kav. 8 , Kel.Jatibaranɡ-
Kec.Mijen,Semaranɡ,Indonesia
Telephone:(
62 )- 24 - 7472849
Japan :KUBOTACorporation
EnɡineExportDept.
2 - 47 ,Shikitsuhiɡashi 1 -chome,Naniwa-ku,Osaka,Japan 556 - 8601
Telephone:( 81 ) 6 - 6648 - 2155 Fax:( 81 ) 6 - 6648 - 3521
OPERATOR'S MANUAL
KUBOTA LIQUID COOLED GASOLINE
/
LPG ENGINE
MANUEL DE L'OPERATEUR
MOTEUR À ESSENCE
/
LPG REFROIDI PAR LIQUIDE DE KUBOTA
BEDIENUNGSANLEITUNG
FLÜSSIGKEITSGEKÜHLTER BENZIN-
/
LPG-MOTOR VON KUBOTA
MANUALE DELL'OPERATORE
MOTORE KUBOTA A BENZINA
/
LPG CON RAFFREDDAMENTO A LIQUID O
MANUAL DE INSTRUCCIONES
MOTOR KUBOTA DE GASOLINA
/
LPG REFRIGERADO POR LÍQUIDO
Code No. EG523-8917-4
WG1605-G-E3
WG1605-L-E 3
WG1605-GL-E3
WG1605-N-E3
WG1605-LN-E3
WG1903-G-E3
WG1903-L-E 3
WG1903-GL-E3
WG1903-N-E3
WG1903-LN-E3
WG2503-G-E3
WG2503-L-E 3
WG2503-GL-E3
WG2503-N-E3
WG2503-LN-E3
WG3800-G-E3
WG3800-L-E 3
WG3800-GL-E3
WG3800-N-E3
WG3800-LN-E3
1BGAAAIAP0020 1BGAAAIAP0540 1BGAAAIAP0220 1BGAAAIAP0440
1904-0508
READ AND SAVE THIS BOOK
MANUEL A LIRE ET A CONSERVER
DIESE ANLEITUNG BITTE SORGFÄLTIG DURCHLESEN
UND GRIFFBEREIT AUFBEWAHREN
LEGGETE E CONSERVATE QUESTO MANUALE
LEAN Y CONSERVEN ESTE MANUAL

1904-0508
WG1605-G-E3/WG1605-L-E3/WG1605-GL-E3/WG1605-N-E3/WG1605-LN-E3
WG1903-G-E3/WG1903-L-E3/WG1903-GL-E3/WG1903-N-E3/WG1903-LN-E3
WG2503-G-E3/WG2503-L-E3/WG2503-GL-E3/WG2503-N-E3/WG2503-LN-E3
WG3800-G-E3/WG3800-L-E3/WG3800-GL-E3/WG3800-N-E3/WG3800-LN-E3
AX. F. 17-31. 10. K
California Proposition 65
Engine exhaust, some of its constituents,
certain vehicle components and fluids,
contain or emit chemicals known to the
State of California to cause cancer and birth
defects or other reproductive harm.
WARNING

MODELS
WG1605-G-E3
WG1605-L-E 3
WG1605-GL-E3
WG1605-N-E3
WG1605-LN-E3
WG1903-G-E3
WG1903-L-E 3
WG1903-GL-E3
WG1903-N-E3
WG1903-LN-E3
WG2503-G-E3
WG2503-L-E 3
WG2503-GL-E3
WG2503-N-E3
WG2503-LN-E3
WG3800-G-E3
WG3800-L-E 3
WG3800-GL-E3
WG3800-N-E3
WG3800-LN-E3
1BGAAAIAP0020 1BGAAAIAP0540 1BGAAAIAP0220 1BGAAAIAP0440
OPERATOR'S MANUAL
KUBOTA
LIQUID COOLED
GASOLINE
/
LPG ENGINE
READ AND SAVE THIS BOOK

ENGLISH
You are now the proud owner of a KUBOTA Engine. This engine is a
product of KUBOTA quality engineering and manufacturing. It is made
of fine materials and under a rigid quality control system. It will give
you long, satisfactory service. To obtain the best use of your engine,
please read this manual carefully. It will help you become familiar with
the operation of the engine and contains many helpful hints about
engine maintenance. It is KUBOTA's policy to utilize as quickly as
possible every advance in our research. The immediate use of new
techniques in the manufacture of products may cause some small
parts of this manual to be outdated. KUBOTA distributors and dealers
will have the most up-to-date information. Please do not hesitate to
consult with them.
This symbol, the industry's "Safety Alert Symbol", is used throughout
this manual and on labels on the machine itself to warn of the
possibility of personal injury. Read these instructions carefully. It is
essential that you read the instructions and safety regulations before
you attempt to assemble or use this unit.
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, could result in minor or moderate
injury.
IMPORTANT : Indicates that equipment or property damage
could result if instructions are not followed.
NOTE : Gives helpful information.
FOREWORD
SAFETY FIRST

CONTENTS
ENGLISH
SAFE OPERATION ..................................................................................................1
SERVICING OF THE ENGINE ....................................................................................1
IMPORTANT INFORMATION OF EMISSION REGULATION.....................................2
NAMES OF PARTS .....................................................................................................3
PRE-OPERATION CHECK..........................................................................................8
BREAK-IN.................................................................................................................8
DAILY CHECK..........................................................................................................8
OPERATING THE ENGINE .........................................................................................9
STARTING THE ENGINE (NORMAL)......................................................................9
STOPPING THE ENGINE ......................................................................................11
CHECKS DURING OPERATION ...........................................................................12
Radiator cooling water (Coolant) .................................................................................... 12
Oil pressure lamp ........................................................................................................... 12
Immediately stop the engine if;....................................................................................... 12
If MIL (Malfunction Indicator Light) lights up:.................................................................. 12
EMISSION CONTROL SYSTEM............................................................................12
MAINTENANCE .........................................................................................................13
SERVICE INTERVALS...........................................................................................14
PERIODIC SERVICE .................................................................................................20
FUEL ......................................................................................................................20
Gasoline ......................................................................................................................... 20
Fuel level check and refueling........................................................................................ 20
Checking the fuel pipes .................................................................................................. 20
LPG ................................................................................................................................ 20
LPG leakage check ....................................................................................................... 20
LPG fuel tank check ....................................................................................................... 20
LPG regulator check....................................................................................................... 20
NG .................................................................................................................................. 21
NG leakage check .......................................................................................................... 21
NG fuel tank check ......................................................................................................... 21
NG regulator check ........................................................................................................ 21
NG line check ................................................................................................................. 21
ENGINE OIL ...........................................................................................................21
Checking oil level and adding engine oil ........................................................................ 22
Changing engine oil........................................................................................................ 23
Replacing the oil filter cartridge ...................................................................................... 24
SPARK PLUG.........................................................................................................25
Cleaning and adjustment clearance .............................................................................. 25
RADIATOR .............................................................................................................26
Checking coolant level, adding coolant .......................................................................... 26
Changing coolant ........................................................................................................... 28
Remedies for quick decrease of coolant ........................................................................ 28
Checking radiator hoses and clamp bands .................................................................... 28
Precaution at overheating .............................................................................................. 28
Cleaning radiator core (outside) ..................................................................................... 28
Anti-freeze ...................................................................................................................... 29
AIR CLEANER........................................................................................................30
EG523-8917_E.book Page 1 Friday, May 17, 2019 10:32 AM

CONTENTS
ENGLISH
Cleaning primary air cleaner element............................................................................. 30
Evacuator valve.............................................................................................................. 30
For the air cleaner with a dust cup (optional) ................................................................. 30
Dust indicator (optional) ................................................................................................. 30
FUEL SYSTEM AND DIAGRAMS..........................................................................31
LPG fuel system ............................................................................................................. 31
Tightening torques and leak check for LPG regulator with vaporizer............................. 31
NG fuel system............................................................................................................... 31
Fuel system diagrams .................................................................................................... 32
ELECTRIC WIRING ...............................................................................................34
FAN BELT ..............................................................................................................34
Adjusting fan belt tension ............................................................................................... 34
OIL SEPARATOR...................................................................................................35
Changing of oil separator element ................................................................................. 35
RUBBER PIPING RELATED OIL SEPARATOR ....................................................35
Replacement of rubber piping related oil separator ....................................................... 35
CARRIAGE AND STORAGE .....................................................................................36
CARRIAGE .............................................................................................................36
STORAGE ..............................................................................................................36
TROUBLESHOOTING ...............................................................................................37
SPECIFICATIONS .....................................................................................................40
EG523-8917_E.book Page 2 Friday, May 17, 2019 10:32 AM

1SAFE OPERATION
ENGLISH
SAFE OPERATION
Careful operation is your best assurance against an accident. Read and understand this
section carefully before operating the engine. All operators, no matter how much
experience they may have, should read this and other related manuals before operating
the engine or any equipment attached to it. It is the owner's obligation to provide all
operators with this information and instruct them on safe operation.
Be sure to observe the following for safe operation.
1.OBSERVE SAFETY INSTRUCTIONS
ARead and understand carefully this "OPERATOR'S
MANUAL" and "LABELS ON THE ENGINE" before
attempting to start and operate the engine.
ALearn how to operate and work safely. Know your
equipment and its limitations. Always keep the engine in
good condition.
ABefore allowing other people to use your engine, explain
how to operate and have them read this manual before
operation.
ADO NOT modify the engine. UNAUTHORIZED
MODIFICATIONS to the engine may impair the function
and/or safety and affect engine life. If the engine does not
perform properly, consult your local Kubota Engine
Distributor first.
2. WEAR SAFE CLOTHING AND PERSONAL PROTECTIVE EQUIPMENT (PPE)
ADO NOT wear loose, torn or bulky clothing around the
machine that may catch on working controls and
projections or into fans, pulleys and other moving parts
causing personal injury.
AUse additional safety items-PPE, e.g. hard hat, safety
protection, safety goggles, gloves, etc., as appropriate or
required.
ADO NOT operate the machine or any equipment attached
to it while under the influence of alcohol, medication, or
other drugs, or while fatigued.
ADO NOT wear radio or music headphones while
operating the engine.
EG523-8917_E.book Page 1 Friday, May 17, 2019 10:32 AM

SAFE OPERATION2
ENGLISH
3. CHECK BEFORE STARTING & OPERATING THE ENGINE
ABe sure to inspect the engine before operation. Do not
operate the engine if there is something wrong with it.
Repair it immediately.
AEnsure all guards and shields are in place before
operating the engine. Replace any that are damaged or
missing.
ACheck to see that you and others are a safe distance
from the engine before starting.
AAlways keep the engine at least 3 feet (1 meter) away
from buildings and other facilities.
ADO NOT allow children or livestock to approach the
machine while the engine is running.
ADO NOT start the engine by shorting across starter
terminals.
4. KEEP THE ENGINE AND SURROUNDINGS CLEAN
ABe sure to stop the engine before cleaning.
AKeep the engine clean and free of accumulated dirt,
grease and trash to avoid a fire. Store flammable fluids in
proper containers and cabinets away from sparks and
heat.
ACheck for and repair leaks immediately.
ADO NOT stop the engine without idling; Allow the engine
to cool down, first. Keep the engine idling for about 5
minutes before stopping unless there is a safety problem
that requires immediate shut down.
5. SAFE HANDLING OF FUEL AND LUBRICANTS -KEEP AWAY FROM FIRE
AAlways stop the engine before refueling and/or
lubricating.
ADO NOT smoke or allow flames or sparks in your work
area. Fuel is extremely flammable and explosive under
certain conditions.
ARefuel at a well ventilated and open place. When fuel
and/or lubricants are spilled, refuel after letting the
engine cool down.
ADo not use unapproved containers e.g. buckets, bottles,
jars. Use approved fuel storage containers and
dispensers.
EG523-8917_E.book Page 2 Friday, May 17, 2019 10:32 AM

3SAFE OPERATION
ENGLISH
AIf running the engine on LPG, use the standard LPG fuel
recommended by KUBOTA. The use of other fuel may
cause a hazardous or dangerous condition.
ALPG fuel in the gaseous state is heavier than air and will
settle in low areas, this may be hazardous.
Please follow all operator's manual instructions when
changing the fuel tank and servicing the fuel system.
6. EXHAUST GASES & FIRE PREVENTION
AEngine exhaust fumes can be very harmful if allowed to
accumulate. Be sure to run the engine in a well ventilated
location and where there are no people or livestock near
the engine.
AThe exhaust gas from the muffler is very hot. To prevent
a fire, do not expose dry grass, mowed grass, oil or any
other combustible materials to exhaust gas. Keep the
engine and muffler clean at all times.
ATo avoid a fire, be alert for leaks of flammable
substances from hoses and lines. Be sure to check for
leaks from hoses or pipes, such as fuel and hydraulic
fluid by following the maintenance check list.
ATo avoid a fire, do not short across power cables and
wires. Check to see that all power cables and wirings are
in good condition. Keep all electrical connections clean.
Bare wire or frayed insulation can cause a dangerous
electrical shock and personal injury.
7. ESCAPING FLUID
ARelieve all pressure in the air, the oil and the cooling
systems before disconnecting any lines, fittings or
related items.
ABe cautious of possible pressure relief when
disconnecting any device from a pressurized system that
utilizes pressure. DO NOT check for pressure leaks with
your hand. High pressure oil or fuel can cause personal
injury.
AEscaping fluid under pressure has sufficient force to
penetrate skin causing serious personal injury.
AFluid escaping from pinholes may be invisible. Use a
piece of cardboard or wood to search for suspected
leaks: do not use hands and body. Use safety goggles or
other eye protection when checking for leaks.
AIf injured by escaping fluid, see a medical doctor
immediately. This fluid can produce gangrene or severe
allergic reaction.
EG523-8917_E.book Page 3 Friday, May 17, 2019 10:32 AM

SAFE OPERATION4
ENGLISH
8. CAUTIONS AGAINST BURNS & BATTERY EXPLOSION
ATo avoid burns, be cautious of hot components, e.g.
muffler, muffler cover, radiator, hoses, engine body,
coolants, engine oil, etc. during operation and after the
engine has been shut off.
ADO NOT remove the radiator cap while the engine is
running or immediately after stopping. Otherwise hot
water will spout out from the radiator. Wait until the
radiator is completely cool to the touch before removing
the cap. Wear safety goggles.
ABe sure to close the coolant drain valve, secure the
pressure cap, and fasten the pipe band before operating.
If these parts are taken off, or loosened, it will result in
serious personal injury.
AThe battery presents an explosive hazard. When the
battery is being charged, hydrogen and oxygen gases
are extremely explosive.
ADO NOT use or charge the battery if its fluid level is below
the LOWER mark.
Otherwise, the component parts may deteriorate earlier
than expected, which may shorten the service life or
cause an explosion. Immediately, add distilled water until
the fluid level is between the UPPER and LOWER marks.
AKeep sparks and open flames away from the battery,
especially during charging. DO NOT strike a match near
the battery.
ADO NOT check the battery charge by placing a metal
object across the terminals. Use a voltmeter or
hydrometer.
ADO NOT charge a frozen battery. There is a risk of
explosion. When frozen, warm the battery up to at least
16 C (61 F).
9. KEEP HANDS AND BODY AWAY FROM ROTATING PARTS
ABe sure to stop the engine before checking or adjusting
the belt tension and cooling fan.
AKeep your hands and body away from rotating parts,
such as the cooling fan, V-belt, fan drive pulley or
flywheel. Contact with rotating parts can cause severe
personal injury.
ADO NOT run the engine without safety guards. Install
safety guards securely before operation.
EG523-8917_E.book Page 4 Friday, May 17, 2019 10:32 AM

5SAFE OPERATION
ENGLISH
10. ANTI-FREEZE & DISPOSAL OF FLUIDS
AAnti-freeze is poisonous. If it is swallowed, seek immediate
medical help. Do NOT make a person throw up unless told
to do so by poison control or a health care professional. Use
standard first aid and CPR for signs of shock or cardiac
arrest. Call your local Poison Control Center or your local
emergency number for further assistance.
AWear rubber gloves to avoid personal injury, when you
treat anti-freeze. In case of contact with skin, wash it off
immediately.
ADO NOT mix different types of Anti-freeze. The mixture can
produce a chemical reaction causing harmful substances.
Use approved or genuine KUBOTA Anti-freeze.
ABe mindful of the environment and the ecology. Before
draining any fluids, determine the correct way to dispose
of them. Observe the relevant environmental protection
regulations when disposing of oil, fuel, coolant, brake
fluid, filters and batteries.
AWhen draining fluids from the engine, place a suitable
container underneath the engine body.
ADO NOT pour waste onto the ground, down a drain, or
into any water source. Dispose of waste fluids according
to environmental regulations.
11. CONDUCTING SAFETY CHECKS & MAINTENANCE
AWhen inspecting the engine or servicing, place the engine
on a large flat surface. DO NOT work on anything that is
supported ONLY by lift jacks or a hoist. Always use blocks
or the correct stands to support the engine before servicing.
ADisconnect the battery from the engine before
conducting service. Put a "DO NOT OPERATE!" tag on
the key switch to avoid accidental starting.
ATo avoid sparks from an accidental short circuit always
disconnect the battery's ground cable (-) first and
reconnect it last.
ABe sure to stop the engine and remove the key when
conducting daily and periodic maintenance, service and
cleaning.
ACheck or conduct maintenance after the engine, coolant,
muffler, or muffler cover have cooled off completely.
AAlways use the appropriate tools and fixtures. Verify that
they are in good condition before performing any service
work. Make sure you understand how to use them before
service.
AUse ONLY correct engine barring techniques for
manually rotating the engine. DO NOT attempt to rotate
the engine by pulling or prying on the cooling fan and V-
belt. This practice can cause serious personal injury or
premature damage to the cooling fan and belt.
EG523-8917_E.book Page 5 Friday, May 17, 2019 10:32 AM

SAFE OPERATION6
ENGLISH
1. Keep warning and caution labels clean and free from obstructing material.
2. Clean warning and caution labels with soap and water, dry with a soft cloth.
3. Replace damaged or missing warning and caution labels with new labels from your local
KUBOTA dealer.
4. If a component with warning and caution label(s) affixed is replaced with a new part, make
sure the new label(s) is (are) attached in the same location(s) as the replaced component.
5. Mount new warning and caution labels by applying to a clean dry surface and pressing any
bubbles to the outside edge.
AReplace fuel pipes and lubricant pipes with their hose
clamps every 2 years or earlier whether they are
damaged or not. They are made of rubber and age
gradually.
AWhen servicing is performed together by two or more
persons, take care to perform all work safely.
AKeep a first aid kit and fire extinguisher handy at all times.
12. WARNING AND CAUTION LABELS
13. CARE OF WARNING AND CAUTION LABELS
EG523-8917_E.book Page 6 Friday, May 17, 2019 10:32 AM

1SERVICING OF THE ENGINE
ENGLISH
SERVICING OF THE ENGINE
Your dealer is interested in your new engine and has the
desire to help you get the most value from it. After reading
this manual thoroughly, you will find that you can do some
of the regular maintenance yourself.
However, when in need of parts or major service, be sure
to see your KUBOTA dealer.
For service, contact the KUBOTA Dealership from which
you purchased your engine or your local KUBOTA dealer.
When in need of parts, be prepared to give your dealer
the engine serial number.
Locate the serial number now and record them in the
space provided.
[WG1605-G-E3 / WG1605-L-E3 / WG1605-GL-E3 /
WG1605-N-E3 / WG1605-LN-E3]
[WG1903-G-E3 / WG1903-L-E3 / WG1903-GL-E3 /
WG1903-N-E3 / WG1903-LN-E3]
[WG2503-G-E3 / WG2503-L-E3 / WG2503-GL-E3 /
WG2503-N-E3 / WG2503-LN-E3]
[WG3800-G-E3 / WG3800-L-E3 / WG3800-GL-E3 /
WG3800-N-E3 / WG3800-LN-E3]
Type Serial No.
Engine
Date of Purchase
Name of Dealer
(To be filled in by purchaser)
(1) Engine serial number
(1) Engine serial number
(1) Engine serial number
(1) Engine serial number
EG523-8917_E.book Page 1 Friday, May 17, 2019 10:32 AM

2 IMPORTANT INFORMATION OF EMISSION REGULATION
ENGLISH
IMPORTANT INFORMATION OF EMISSION REGULATION
1. EXHAUST SYSTEM (COMMON)
THE WG1605-E3 ENGINE MUST USE THE BELOW CATALYTIC PARTS.
THE WG1903-E3 ENGINE MUST USE THE BELOW CATALYTIC PART.
THE WG2503-E3 ENGINE MUST USE THE BELOW CATALYTIC PART.
THE WG3800-E3 ENGINE MUST USE THE BELOW CATALYTIC PART.
Any modifications to the fuel system or any adjustments made on this engine will cause this engine to be in non-
compliance with emission regulations.
2. LPG REGULATOR WITH VAPORIZER (WG1605-L-E3 / WG1605-GL-E3 / WG1605-LN-E3 / WG1903-L-E3 /
WG1903-GL-E3 / WG1903-LN-E3 / WG2503-L-E3 / WG2503-GL-E3 / WG2503-LN-E3 / WG3800-L-E3 / WG3800-
GL-E3 / WG3800-LN-E3)
When operating WG1605-L-E3 / WG1605-GL-E3 / WG1605-LN-E3 / WG1903-L-E3 / WG1903-GL-E3 / WG1903-LN-E3 /
WG2503-L-E3 / WG2503-GL-E3 / WG2503-LN-E3 / WG3800-L-E3 / WG3800-GL-E3 / WG3800-LN-E3 on LPG, only a
KUBOTA genuine regulator assy (D-STAGE) and lock off valve with LPG filter can be used.
Only this regulator assy (D-STAGE) and lock off valve with LPG filter can be installed by an authorized KUBOTA
DISTRIBUTOR or the manufacturer of the equipment in which this engine is used.
To conform to U.S. EPA Phase 3, CARB LSI (Large SI) and EU stage V emission regulations,
the following standards must be followed before using the WG1605-E3 / WG1903-E3 /
WG2503-E3 / WG3800-E3 engine.
GENUINE PART PART NO.
CATALYTIC CONVERTER EG523-1212
CATALYTIC MUFFLER EG526-1211
EG541-1211
GENUINE PART PART NO.
CATALYTIC CONVERTER EG523-1212
GENUINE PART PART NO.
CATALYTIC CONVERTER EG543-1212
CATALYTIC MUFFLER EG541-1211
GENUINE PART PART NO.
CATALYTIC CONVERTER EG504-1212
EG523-8917_E.book Page 2 Friday, May 17, 2019 10:32 AM

3NAMES OF PARTS
ENGLISH
NAMES OF PARTS
[WG1605-G-E3 / WG1605-L-E3 / WG1605-GL-E3 / WG1605-N-E3 / WG1605-LN-E3]
G Type : WG1605-G-E3, L Type : WG1605-L-E3, GL Type : WG1605-GL-E3, N Type : WG1605-N-E3,
LN Type : WG1605-LN-E3
A(25) ECU (Engine Control Unit) is not connected to the engine in the figure above.
Ref.
No. Part Name Type Ref. No. Part Name Type
GLGLNLN GLGLNLN
(1) Oil filler plug (14) Electronic control throttle
(2) Delivery pipe (gasoline) - - - (15) Injector - - -
(3) Plug ignition coil (16) Gas mixer -
(4) Spark plug (17) Pressure regulator -
(5) PCV valve (18) Intake manifold
(6) Engine hook (19) Cooling fan
(7) Oil level gauge (20) Fan belt
(8) Exhaust manifold (21) Fan drive pulley
(9) Starter (22) Oil drain plug
(10) Alternator (23) Oil pan
(11) Coolant drain shutoff-valve (24) Flywheel
(12) Oil filter cartridge (25) ECU (Engine Control Unit)
(13) Oil pressure switch
EG523-8917_E.book Page 3 Friday, May 17, 2019 10:32 AM

4 NAMES OF PARTS
ENGLISH
[WG1903-G-E3 / WG1903-L-E3 / WG1903-GL-E3 / WG1903-N-E3 / WG1903-LN-E3]
G Type : WG1903-G-E3, L Type : WG1903-L-E3, GL Type : WG1903-GL-E3, N Type : WG1903-N-E3,
LN Type : WG1903-LN-E3
AGas mixer has two models.
N and LN type’s gas mixer are different from L and GL type.
Ref.
No. Part Name Type Ref. No. Part Name Type
GLGLNLN GLGLNLN
(1) Engine hook (13) Alternator
(2) Oil filler plug (14) Intake manifold
(3) PCV valve (15) Electronic control throttle
(4) Delivery pipe (gasoline) - - - (16) Injector - - -
(5) Plug ignition coil (17) Gas mixer -
(6) Spark plug (18) Pressure regulator -
(7) Exhaust manifold (19) Cooling fan
(8) Flywheel (20) Fan belt
(9) Oil drain plug (21) Fan drive pulley
(10) Oil pan (22) Oil filter cartridge
(11) Starter (23) Oil level gauge
(12) Oil pressure switch (24) ECU (Engine Control Unit)
EG523-8917_E.book Page 4 Friday, May 17, 2019 10:32 AM

5NAMES OF PARTS
ENGLISH
[WG2503-G-E3 / WG2503-L-E3 / WG2503-GL-E3 / WG2503-N-E3 / WG2503-LN-E3]
G Type : WG2503-G-E3, L Type : WG2503-L-E3, GL Type : WG2503-GL-E3, N Type : WG2503-N-E3,
LN Type : WG2503-LN-E3
AGas mixer has two models.
N and LN type’s gas mixer are different from L and GL type.
Ref.
No. Part Name Type Ref. No. Part Name Type
GLGLNLN GLGLNLN
(1) Engine hook (13) Alternator
(2) Oil filler plug (14) Intake manifold
(3) PCV valve (15) Electronic control throttle
(4) Delivery pipe (gasoline) - - - (16) Injector - - -
(5) Plug ignition coil (17) Gas mixer -
(6) Spark plug (18) Pressure regulator -
(7) Exhaust manifold (19) Cooling fan
(8) Flywheel (20) Fan belt
(9) Oil drain plug (21) Fan drive pulley
(10) Oil pan (22) Oil filter cartridge
(11) Starter (23) Oil level gauge
(12) Oil pressure switch (24) ECU (Engine Control Unit)
EG523-8917_E.book Page 5 Friday, May 17, 2019 10:32 AM

6 NAMES OF PARTS
ENGLISH
[WG3800-G-E3 / WG3800-L-E3 / WG3800-GL-E3 / WG3800-N-E3 / WG3800-LN-E3]
G Type : WG3800-G-E3, L Type : WG3800-L-E3, GL Type : WG3800-GL-E3, N Type : WG3800-N-E3,
LN Type : WG3800-LN-E3
AGas mixer has two models.
N and LN type's gas mixer are different from L and GL type.
AThe part marked *1 is optional. It is required for continuous operation over 15 hours (day and night) ex. Generator,
Pump.
Ref.
No. Part Name Type Ref.
No. Part Name Type
GLGLNLN GLGLNLN
(1) Engine hook (13) Alternator
(2) Oil filler plug (14) Intake manifold
(3) PCV valve (15) Electronic control throttle
(4) Plug ignition coil (16) Gas mixer -
(5) Spark plug (17) Pressure regulator -
(6) Exhaust manifold (18) Cooling fan
(7) Flywheel (19) Fan belt
(8) Oil drain plug (20) Fan drive pulley
(9) Oil pan (21) Oil filter cartridge
(10) Starter (22) Oil level gauge
(11) Oil pressure switch (23) ECU (Engine Control
Unit)
(12) Delivery pipe (gasoline) - - - (24) Injector - - -
(25) Oil separator - *1 - *1 *1
EG523-8917_E.book Page 6 Friday, May 17, 2019 10:32 AM

7NAMES OF PARTS
ENGLISH
G Type : WG1605-G-E3 / WG1903-G-E3 / WG2503-G-E3 / WG3800-G-E3
L Type : WG1605-L-E3 / WG1903-L-E3 / WG2503-L-E3 / WG3800-L-E3
GL Type : WG1605-GL-E3 / WG1903-GL-E3 / WG2503-GL-E3 / WG3800-GL-E3
N Type : WG1605-N-E3 / WG1903-N-E3 / WG2503-N-E3 / WG3800-N-E3
LN Type : WG1605-LN-E3 / WG1903-LN-E3 / WG2503-LN-E3 / WG3800-LN-E3
Ref.
No. Part Name Type Remarks
GLGLNLN
(1) Sensor (O2)
(2) Fuel pump - - -
(3) Manifold (FPM) - - -
(4) Regulator assy (D-STAGE) - -
(5) Lock off valve - -
(6) Catalytic converter or catalytic muffler
(7) Catalytic muffler
[Except WG3800-E3] or catalytic converter
EG523-8917_E.book Page 7 Friday, May 17, 2019 10:32 AM

8 PRE-OPERATION CHECK
ENGLISH
PRE-OPERATION CHECK
BREAK-IN
During the engine break-in period, observe the following by all means:
1. Change engine oil and oil filter cartridge after the first 50 hours of operation. (See "ENGINE OIL" in "PERIODIC
SERVICE" section.)
2. When ambient temperature is low, operate the machine after the engine has been completely warmed up.
DAILY CHECK
To prevent trouble from occurring, it is important to know the conditions of the engine well. Check it before starting.
To avoid personal injury or death:
ABe sure to install shields and safeguards attached to the engine when operating.
AStop the engine at a flat and wide space when checking.
AKeep dust or fuel away from the battery, wiring, muffler and engine to prevent a fire.
Check and clear them before operating everyday. Pay attention to the heat of the
exhaust pipe or exhaust gas so that it can not ignite trash.
Item Ref. page
1. Parts which had trouble in previous operation -
2. By walking around the machine (1) Oil or water leaks 22 to 29
(2) Engine oil level and contamination 22, 23
(3) Amount of fuel 20
(4) Amount of coolant 26 to 29
(5) Dust in air cleaner dust cup 30
(6) Damaged parts and loosened bolts and nuts -
3. By inserting the key into the starter
switch
(1) Proper functions of meters and pilot lamps; no stains on
these parts -
4. By starting the engine (1) Unusual engine noise 12
(2) Engine start-up condition 9
(3) Slow-down and acceleration behavior 12
EG523-8917_E.book Page 8 Friday, May 17, 2019 10:32 AM