Jacobsen SXG323 User manual

LAWN MOWERS:
MOWER DECKS:
COLLECTORS:
SCMB48 & SCMA54
SBC550X & 600X

ISEKI LAWN MOWERS
1
This service manual has been prepared to provide the information and suggestions necessary
for servicing the ISEKI SXG Lawn Mower. These include construction, specifications, removal
and reinstallation of the components, disassembly and reassembly instructions, inspection and
adjustment instructions, troubleshooting, general precautions etc.
Figures mentioned in this manual are standard values established by ISEKI for the SXG,
consequently when a non-ISEKI part has been installed on the machine or adjustments and
repairs have been made in a manner other than as specified in this manual, the pertinent values
mentioned herein are no longer valid. ISEKI does not assume responsibility for problems or
damage caused by a value deviation due to maladjustment or by the use of unauthorized parts.
Servicing procedures outlined in the manual contain sufficient information to return all
component parts of a machine to new condition. In discussion of each component part, it is
assumed that a complete overhaul is being performed, consequently, complete disassembly and
reassembly are outlined. The machine is relied upon to decide how far disassembly must be
carried out when complete overhaul is not required.
Study unfamiliar service procedures thoroughly and understand them clearly before attempting
disassembly. Specific data essential for proper overhaul, such as running clearances and torque
values, have been provided in interline of inspection and reassembling procedures of each
group section.
This manual was compiled from latest information available at time of publication, However
ISEKI reserves the right to make changes at any time without notice.
Whenever the terms “left” and“ right” are used, this means as viewed by the operator when
seated in the operator’s seat.
Whenever servicing the machines, pay sufficient attention to the operational safety to protect you
and other persons around the machines from danger by following carefully the instructions given
in the manual. Never take chances!
FOREWORD

SERVICE MANUAL FOR SXG323&326
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TOTAL CONTENTS
LAWN MOWERS
CHAPTER 1. GENERAL INFORMATION ......................................................................................11
CHAPTER 2. DISASSEMBLY OF MAJOR COMPONENTS..........................................................17
CHAPTER 3. ENGINE ACCESSORIES.........................................................................................27
CHAPTER 4. ENGINE ....................................................................................................................33
CHAPTER 5. LUBRICATION SYSTEM..........................................................................................67
CHAPTER 6. COOLING SYSTEM..................................................................................................73
CHAPTER 7. FUEL SYSTEM.........................................................................................................75
CHAPTER 8. TRANSMISSION AND RELATED PARTS ...............................................................87
CHAPTER 9. REAR AXLE .............................................................................................................93
CHAPTER 10. HYDROSTATIC TRANSMISSION..........................................................................95
CHAPTER 11. HYDRAULIC SYSTEM .........................................................................................117
CHAPTER 12. POWER STEERING SYSTEM .............................................................................121
CHAPTER 13. ELECTRICAL ACCESSORIES ............................................................................127
MOWER DECKS
CHAPTER 1. FOR SAFETY LABELS..............................................................................................5
CHAPTER 2. SPECIFICATIONS ......................................................................................................7
CHAPTER 3. ATTACHING AND DETACHING THE MOWER DECK..............................................9
CHAPTER 4. MOWER OPERATION..............................................................................................11
CHAPTER 5. INSPECTION AND MAINTAINANCE OF MAJOR PARTS......................................17
CHAPTER 6. DISASSEMBLY AND REASSEMBLY OF GEAR BOX............................................25
CHAPTER 7. INSPECTION OF MOWER DECK SCMA TYPE......................................................29
CHAPTER 8. TROUBLESHOOTING..............................................................................................33
COLLECTORS
CHAPTER 1. SAFETY LABELS.......................................................................................................5
CHAPTER 2. SPECIFICATIONS ......................................................................................................7
CHAPTER 3. NAME OF MAJOR COMPONENTS...........................................................................9
CHAPTER 4. DETACHING AND ATTACHING THE COLLECTOR............................................... 11
CHAPTER 5. COLLECTOR OPERATION......................................................................................15
CHAPTER 6. INSPECTION AND MAINTAINANCE OF MAJOR PARTS......................................17
CHAPTER 7. ASSEMBLY INSTRUCTION.....................................................................................21
CHAPTER 8. TROUBLESHOOTING..............................................................................................47

I
S
EKI LAWN M
O
WER
S
S
X
G
323 & 32
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ISEKI LAWN MOWERS
SXG323 & 326
CHAPTER 1
CHAPTER 2
CHAPTER 3
CHAPTER 4
CHAPTER 5
CHAPTER 6
CHAPTER 7
CHAPTER 8
CHAPTER 9
CHAPTER 10
CHAPTER 11
CHAPTER 12
CHAPTER 13

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TABLE OF CONTENTS
FOREWORD.....................................................................................................................................1
TOTAL CONTENTS..........................................................................................................................2
TABLE OF CONTENTS....................................................................................................................5
CHAPTER 1. GENERAL INFORMATION ......................................................................................11
1. MODEL NAME AND IDENTIFICATIONS NUMBERS.............................................................. 11
2. SPECIFICATIONS...................................................................................................................12
3. EXTERIOR VIEW ....................................................................................................................13
4. PERIODIC INSPECTION TABLE ............................................................................................14
5. FILLING DIAGRAM..................................................................................................................15
CHAPTER 2. DISASSEMBLY OF MAJOR COMPONENTS..........................................................17
1. GENERAL PRECAUTIONS FOR SEPARATION AND REINSTALLATION.............................17
1.1. BEFORE OPERATION.....................................................................................................17
1.2. PRECAUTIONS TO BE FOLLOWED WHEN INSTALLING COMMON PARTS...............17
2. DISASSEMBLY OF FUNCTIONAL BLOCKS ..........................................................................20
2.1. REMOVAL OF THE MOWER DECK ................................................................................20
2.2. DETACHING THE COLLECTOR......................................................................................21
2.2.1. DETACHING THE HIGH DUMP COLLECTOR ..........................................................21
2.2.2. DETACHING THE LOW DUMP COLLECTOR...........................................................21
2.3. REMOVAL OF MAJOR FUNCTIONAL COMPONENTS ..................................................22
2.3.1. REMOVAL OF FENDER(WING) PANEL....................................................................22
2.3.2. REMOVAL OF FLOOR STEP, COVER AND FUEL TANK..........................................22
2.3.3. REMOVAL OF STEERING HEEL,METER PANEL.....................................................23
2.3.4. REMOVAL OF RADIATOR .........................................................................................23
2.3.5. REMOVAL OF ENGINE..............................................................................................24
2.3.6. REMOVAL OF REARAXLE CASE.............................................................................24
2.3.7. REMOVAL OF TRANSMISSION CASE......................................................................25
2.3.8. REMOVAL OF FRONTAXLE CASE AND STEERING CYLINDER............................25
3. REINSTALLATION...................................................................................................................26
CHAPTER 3. ENGINE ACCESSORIES .........................................................................................27
1. RADIATOR...............................................................................................................................27
2. COOLING FAN AND BELT......................................................................................................28
3. AIR CLEANER.........................................................................................................................29
4. FUEL SYSTEM........................................................................................................................29
5. TROUBLE SHOOTING............................................................................................................31

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CHAPTER 4. ENGINE ....................................................................................................................33
1. ENGINE...................................................................................................................................33
1.1. SPECIFICATIONS............................................................................................................33
1.2. PERFORMANCE CURVES..............................................................................................34
2. INSPECTION AND ADJUSTMENT..........................................................................................35
2.1. INSPECTION OF ENGINE OIL........................................................................................35
2.2. INSPECTION OF FAN BELT............................................................................................35
2.3. INSPECTION AND ADJUSTMENT OF VALVE CLEARANCES.......................................36
2.3.1. Remove the cylinder head cover. ...............................................................................36
2.3.2. Turn the crankshaft by hand so that the piston in No.1 cylinder reaches at
TDC: align the TDC notch in the crankshaft pulley with the pro-jection on the
gear case. ...................................................................................................................36
2.3.3. Insert a feeler gauge of a specified thickness and adjust the clearance with
the adjusting screw......................................................................................................36
2.4. INSPECTION AND ADJUSTMENT OF NOZZLE OPENING PRESSUREAND
INJECTION TIMING..........................................................................................................36
2.4.1. Adjustment of the valve opening pressure of the injection nozzles. ...........................36
2.4.2. Inspection of oil tightness of valve seats ....................................................................37
2.4.3. Spraying condition of injection nozzle.........................................................................37
2.4.4. Inspection and adjustment of injection timing.............................................................37
2.5. COMPRESSION AND UNLOADED IDLING SPEEDS.....................................................39
2.5.1. Inspection of compression..........................................................................................39
2.5.2. Inspection and adjustment of the idling speeds..........................................................39
2.6. INSPECTION OF WATER PUMP.....................................................................................39
2.6.1. Inspection of the pump and pulley..............................................................................39
2.6.2. Inspection of the bearing unit......................................................................................40
2.7. INSPECTION OF THERMOSTAT.....................................................................................40
3. ENGINE BODY........................................................................................................................40
3.1. CYLINDER HEAD.............................................................................................................40
3.1.1. REMOVAL OF THE CYLINDER HEAD ......................................................................41
3.1.2. DISASSEMBLY...........................................................................................................42
3.1.3. INSPECTION..............................................................................................................42
3.1.4. DISASSEMBLY AND INSPECTION OF THE ROCKERARM SHAFT .......................45
3.1.5. INSPECTION OF THE PUSH RODS .........................................................................46
3.1.6. INSTALLATION OF THE CYLINDER HEAD...............................................................46
3.2. GEAR CASE.....................................................................................................................48
3.2.1. EXPLODED VIEW......................................................................................................48
3.2.2. REMOVAL OF THE GEAR CASE...............................................................................48
3.2.3. RE-INSTALLATION OF THE GEAR CASE.................................................................49
3.3. CYLINDER BLOCK ..........................................................................................................50
3.3.1. EXPLODED VIEW......................................................................................................50
3.3.2. DISASSEMBLY OF THE CYLINDER BLOCK............................................................51

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3.3.3. INSPECTION OF CYLINDER BLOCK,CRANKSHAFT, CAMSHAFT,
AND TAPPETS............................................................................................................52
3.3.4. INSPECTION OF PISTONSAND CONNECTING RODS..........................................57
3.3.5. ASSEMBLY OF PISTONAND CONNECTING ROD..................................................59
3.3.6. INSTALLATION OF CRANKSHAFT............................................................................60
3.3.7. INSTALLATION OF PISTON/CON-NECTING-RODASSEMBLIES ...........................61
3.3.8. INSTALLATION OF REAR OIL SEAL.........................................................................62
3.3.9. INSTALLATION OF STRAINER AND OIL PAN ..........................................................62
3.3.10. INSTALLATION OF REAR PLATE AND FLYWHEEL...............................................62
3.3.11. INSTALLATION OF FRONT PLATE AND GEARS....................................................63
CHAPTER 5. LUBRICATION SYSTEM..........................................................................................67
1. GENERAL DESCRIPTION ......................................................................................................67
1.1. LUBRICATION DIAGRAM................................................................................................67
1.2. RELIEF VALVE.................................................................................................................68
1.3. OIL FILTER.......................................................................................................................68
1.4. EXPLODED VIEW OF OIL PUMP....................................................................................69
2. REMOVAL, DISASSEMBLY, INSPECTION AND RE-INSTALLATION OF OIL PUMP............70
2.1. REMOVAL OF OIL PUMP.................................................................................................70
2.2. DISASSEMBLY OF OIL PUMP.........................................................................................70
2.3. INSPECTION....................................................................................................................70
2.4. INSTALLATION OF OIL PUMP.........................................................................................71
3. OIL FILTER..............................................................................................................................71
3.1. REMOVAL OF OIL FILTER...............................................................................................71
3.2. INSTALLATION OF OIL FILTER.......................................................................................71
CHAPTER 6. COOLING SYSTEM..................................................................................................73
1. COOLING SYSTEM DIAGRAM...............................................................................................73
2. THERMOSTAT.........................................................................................................................73
2.1. REMOVAL OF THERMOSTAT..........................................................................................73
2.2. INSTALLATION OF THERMOSTAT..................................................................................73
2.3. INSPECTION OF THERMOSTAT.....................................................................................73
3.WATER PUMP..........................................................................................................................74
3.1. REMOVAL OF WATER PUMP..........................................................................................74
3.2. INSTALLATION OF WATER PUMP..................................................................................74
3.3. INSPECTION OF WATER PUMP.....................................................................................74
CHAPTER 7. FUEL SYSTEM.........................................................................................................75
1. INJECTION PUMP CONSTRUCTION.....................................................................................75
2. REMOVAL, DISASSEMBLY, INSPECTION, RE-ASSEMBLY, AND INSTALLATION...............76
2.1. REMOVAL OF INJECTION PUMP...................................................................................77
2.2. DISASSEMBLY OF INJECTION PUMP ...........................................................................77

SERVICE MANUAL FOR SXG323&326
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2.3. INSPECTION....................................................................................................................79
2.4. RE-ASSEMBLY.................................................................................................................79
3. INJECTION NOZZLES AND HOLDERS..................................................................................81
3.1. REMOVAL OF INJECTION NOZZLESAND HOLDERS ..................................................81
3.2. INSPECTION OF INJECTION NOZZLES........................................................................81
3.3. DISASSEMBLY AND WASHING OF INJECTION NOZZLES...........................................82
3.4. INSTALLATION OF INJECTION NOZZLES AND HOLDERS ..........................................83
3.5. INSTALLATION OF INJECTION NOULES AND HOLDERS ............................................83
4. GOVERNOR............................................................................................................................84
4.1. GOVERNOR CONSTRUCTION.......................................................................................84
4.2. GOVERNOR OPERATION...............................................................................................86
CHAPTER 8. TRANSMISSION AND RELATED PARTS ...............................................................87
1. DRIVE TRAIN DIAGRAM ........................................................................................................87
2. TRANSMISSION......................................................................................................................88
3. REAR WHEEL DRIVING MECHANISM (GE type)..................................................................88
4. BRAKE SYSTEM DISASSEMBLY...........................................................................................90
5. PRECAUTIONS FOR REASSEMBLY.....................................................................................90
6. BRAKE ADJUSTMENT............................................................................................................90
7. DIF-LOCK ADJUSTMENT ......................................................................................................91
CHAPTER 9. REAR AXLE .............................................................................................................93
1. CONSTRUCTION....................................................................................................................93
CHAPTER 10. HYDROSTATIC TRANSMISSION..........................................................................95
1. CONSTRUCTION AND NAMES OF MAJOR COMPONENTS ...............................................95
2. OPERATING DIAGRAM OF HST............................................................................................96
3. FUNCTION ..............................................................................................................................97
3.1. VARIABLE TYPE PUMP...................................................................................................97
3.2. FIXED TYPE MOTOR.......................................................................................................98
3.3. VALVES ............................................................................................................................98
4. DISASSEMBLY AND REASSEMBLY ....................................................................................100
4.1. REQUIRED TOOLS........................................................................................................100
4.2. PRECAUTIONS FOR DISASSEMBLY...........................................................................100
4.3. TROUBLESHOOTING....................................................................................................101
4.4. DISASSEMBLY...............................................................................................................103
4.5. CRITERIA FOR REPLACING WORN PARTS................................................................106
4.6. PRECAUTION BEFORE REASSEMBLY .......................................................................107
4.7. REASSEMBLY................................................................................................................107
4.8. PRECAUTIONS FOR REASSEMBLY.............................................................................111
4.9. LIST OF MAJOR COMPONENTS OF HIST................................................................... 113
4.10. PRECAUTIONS FOR INSTALLATION OF HST UNIT..................................................113

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4.11. PRECAUTIONS AFTER INSTALLATION OF HST UNIT..............................................113
5. ADJUSTMENT OF HIST........................................................................................................114
CHAPTER 11. HYDRAULIC SYSTEM ......................................................................................... 117
1. HYDRAULIC SYSTEM DIAGRAMS......................................................................................117
2. INSPECTION OF MAJOR COMPONENTS...........................................................................119
2.1. SUCTION FILTER...........................................................................................................119
2.2. HYDRAULIC PUMP (GEAR PUMP)............................................................................... 119
2.3. RELIEF VALVE FUNCTION............................................................................................ 119
2.4. RELIEF METAL (support)...............................................................................................120
2.5. OIL FILTER (Relief metal (support) ................................................................................120
CHAPTER 12. POWER STEERING SYSTEM .............................................................................121
1. CONSTRUCTION..................................................................................................................121
2. WORKING PRINCIPLE .........................................................................................................122
2.1. When the steering wheel is in neutral position: ..............................................................122
2.2. When the sterrring wheel is operated:............................................................................122
3. MAJOR TROUBLESAND CAUSES, AND COUNTERMEASURES .....................................123
CHAPTER 13. ELECTRICAL ACCESSORIES ............................................................................127
1. ELECTRICAL COMPORNENS AND WIRE HARNESS ........................................................127
2. WIRING DIAGRAM (E TYPE)................................................................................................129
3. WIRING DIAGRAM (GE TYPE).............................................................................................130
4. STARTER ..............................................................................................................................131
4.1. CONSTRUCTION...........................................................................................................131
4.2. REMOVALAND DISASSEMBLY OF STARTER.............................................................132
4.3. INSPECTION OF COMPONENTS.................................................................................132
4.4. REASSEMBLY OF STARTER ........................................................................................135
4.5. INSPECTION OF THE STARTERAFTER REMOVAL FROM THE TRACTOR .............136
4.6. PERFORMANCE TEST..................................................................................................136
4.7. INSTALLATION OF THE STARTER...............................................................................137
5. ALTERNATOR........................................................................................................................138
5.1. EXPLOTED VIEW, SPECIFICATIONS, AND PERFORMANCE CURVES.....................138
5.2. TROUBLESHOOTING....................................................................................................139
5.3. REMOVALAND DISASSEMBLY....................................................................................139
5.4. INSPECTION..................................................................................................................141
5.5. RE-ASSEMBLY...............................................................................................................144
6. GLOW PLUGS.......................................................................................................................145
6.1. SECTIONAL VIEW .........................................................................................................145
6.2. REMOVAL, INSPECTION, AND RE-ASSEMBLY...........................................................146