Complete workshop repair service manual with electrical wiring diagrams for Komatsu Bulldozer D66S-1, D68E-1, D68P-1. It's the same service manual used by dealers that guaranteed to be fully functional and intact without any missing page.

This Komatsu Bulldozer D66S-1, D68E-1, D68P-1 service & repair manual (including maintenance, overhaul, disassembling & assembling, adjustment, tune-up, operation, inspecting, diagnostic & troubleshooting…) is divided into different sections. Each section covers a specific component or system with detailed illustrations. A table of contents is placed at the beginning of each section. Pages are easily found by category, and each page is expandable for great detail. The printer-ready PDF documents work like a charm on all kinds of devices.

SEBM0142A10 - D66S-1 Shop Manual (SN1001&up).pdf
SEBMU1440102 - Bulldozer D68E-1, D68P-1 Shop Manual (SN1001&up).pdf

EXCERPT:
TABLE OF CONTENTS
10 ENGINE
11 STRUCTURE AND FUNCTION . . . . . . . 11-1
12 TESTING AND ADJUSTING . . . . . . 12-1
13 DISASSEMBLY AND ASSEMBLY . . . . . . . . . 13-1
20 POWER TRAIN
21 STRUCTURE AND FUNCTION . . . . . . . 21 ,..1
22 TESTING AND ADJUSTING . . . . . . 22-1
23 DISASSEMBLY AND ASSEMBLY . . . . . . . . . 23-1
24 MAINTENANCE STANDARD . . . . . . . . . 24-1
30 UNDERCARRIAGE
31 STRUCTURE AND FUNCTION . . . . . . . 31-1
33 DISASSEMBLY AND ASSEMBLY . . . . . . . . . 33-1
34 MAINTENANCE STANDARD . . . . . . . . . 34-1
60 HYDRAULIC SYSTEM
61 STRUCTURE AND FUNCTION . . . . . . . 61-1
62 TESTING AND ADJUSTING . . . . . . 62-1
63 DISASSEMBLY AND ASSEMBLY . . . . . . . . . 63-1
64 MAINTENANCE STANDARD . . . . . . . . . 64-1
70 WORK EQUIPMENT
71 STRUCTURE AND FUNCTION . . . . . . . 71-1
73 DISASSEMBLY AND ASSEMBLY ............... 73-1
74 MAINTENANCE STANDARD ......... 74-1
80 ELECTRIC AND ELECTRONIC SYSTEM
81 STRUCTURE AND FUNCTION . . . . . . . 81-1
…
STRUCTURE AND FUNCTION
HYDRAULIC CYLINDER
General
The hydraulic cylinder is a device which converts fluid energy into mechanical energy moving in a straight line.
There are oil ports at both the head (piston rod end) and bottom ends of the cylinder. If the oil enters at the head end, the piston moves towards the bottom and the oil at the bottom is drained to the tank. In the same way, if the oil enters at the bottom end, the piston moves towards the head and the oil at the head is drained to the tank.
The piston therefore can be moved in two directions.
This type of piston is called a double-acting piston.
Structure and function
1. Cylinder
• The cylinder is made of steel pipe and a bottom plate is welded on at the bottom end.
The inside of the cylinder is finished by honing to prevent wear of the piston rings or oil leakage.
2. Piston valve
• The piston valve is installed in the piston of the blade lift cylinder of the straight-tiltdozer. As shown in the diagram below, the piston valve opens to let the oil on the high pressure side flow to the low pressure side. In this way it functions to relieve the pressure when the piston reaches the end of its stroke.
…

SEBM0142A10 - D66S-1 Shop Manual (SN1001&up)...2
  COVER...2
  CONTENTS...3
  01 GENERAL...36
    GENERAL VIEW...37
    ASSEMBLY DRAWING...38
    SPECIFICATIONS...39
    ENGINE ASSEMBLY DRAWING...41
    ENGINE SPECIFICATIONS...45
    WEIGHT TABLE...46
    TABLE OF OIL AND COOLANT QUANTITIES...47
    OUTLINE...48
    LAYOUT OF LIST ELECTRONIC CONTROL, MONITOR, SENSORS, ACTUATORS AND CONTROLLER...50
    MONITORING SYSTEM...51
  10 ENGINE...52
    11 STRUCTURE AND FUNCTION...52
      ENGINE MOUNT...53
      RADIATOR AND COOLER...54
      FUEL TANK AND PIPING...55
      ENGINE CONTROL...56
    12 TESTING AND ADJUSTING...57
      STANDARD VALUE TABLE...58
      TOOL LIST FOR TESTING AND ADJUSTING...59
      ADJUSTING VALVE CLEARANCE...60
      MEASURING COMPRESSION PRESSURE...61
      TESTING AND ADJUSTING FUEL INJECTION TIMING...62
      TESTING AND ADJUSTING FAN BELT TENSION...64
      MEASURING ENGINE OIL PRESSURE AND TEMPERATURE...65
      MEASURING BLOW-BY PRESSURE...66
    13 DISASSEMBLY AND ASSEMBLY...67
      STARTING MOTOR ASSEMBLY...68
        REMOVAL...68
        INSTALLATION...68
      ALTERNATOR ASSEMBLY...69
        REMOVAL...69
        INSTALLATION...69
      FUEL INJECTION PUMP ASSEMBLY...70
        REMOVAL...70
        INSTALLATION...70
      WATER PUMP ASSEMBLY...71
        REMOVAL...71
        INSTALLATION...71
      NOZZLE HOLDER ASSEMBLY...72
        REMOVAL...72
        INSTALLATION...72
      CYLINDER HEAD ASSEMBLY...73
        REMOVAL...73
        INSTALLATION...80
      TURBOCHARGER ASSEMBLY...89
        REMOVAL...89
        INSTALLATION...89
      AFTER-COOLER CORE ASSEMBLY...90
        REMOVAL...90
        INSTALLATION...91
      RADIATOR ASSEMBLY...92
        REMOVAL...92
        INSTALLATION...92
      ENGINE OIL COOLER ASSEMBLY...94
        REMOVAL...94
        INSTALLATION...94
      ENGINE, RADIATOR ASSEMBLY...95
        REMOVAL...95
        INSTALLATION...96
      ENGINE ASSEMBLY...97
        REMOVAL...97
        INSTALLATION...97
      HOOD ASSEMBLY (SERIAL NO.1001-1399)...98
        OPENING...98
        CLOSING...98
      HOOD ASSEMBLY (SERIAL NO.1400 AND UP)...99
        REMOVAL...99
        INSTALLATION...99
      HST OIL COOLER ASSEMBLY (SERIAL NO.1001-1399)...100
        REMOVAL...100
        INSTALLATION...100
      HST OIL COOLER ASSEMBLY (SERIAL NO.1400 AND UP)...101
        REMOVAL...101
        INSTALLATION...101
  20 POWER TRAIN...102
    21 STRUCTURE AND FUNCTION...102
      GENERAL...103
      POWER TRAIN HYDRAULIC SYSTEM...105
      DAMPER...109
      DRIVE SHAFT (INPUT, OUTPUT)...111
      TORQUE SPLITTER...112
      HST (HYDROSTATIC TRANSMISSION)...114
      HYDROSTATIC TRANSMISSION PIPING...116
      SPEED CONTROL...118
      HYDROSTATIC TRANSMISSION OIL CIRCUIT DIAGRAM...119
      COMPONENTS OF HST (SERIAL NO.1001-1399)...125
      HST PUMP GROUP (SERIAL NO.1001-1399)...126
      COMPONENTS OF HST (SERIAL NO.1400 AND UP)...129
      HST PUMP GROUP (SERIAL NO.1400 AND UP)...130
      HST MOTOR GROUP...159
      HST CHARGING PUMP AND HST SERVO PUMP...166
      HST FILTER...169
      CHARGE OIL FILTER BYPASS VALVE AND CHARGE OIL SAFETY VALVE...170
      HST TANK...173
      STEERING CONTROL...174
      BRAKE CONTROL...175
      BRAKE AND BRAKE CONTROL VALVE...176
      FINAL DRIVE...185
    22 TESTING AND ADJUSTING...187
      STANDARD VALUE TABLE...188
      TESTING AND ADJUSTING...190
        BLEEDING AIR FROM HST BRAKE CIRCUIT...190
        TESTING AND ADJUSTING HYDRAULIC PRESSURE...191
        MEASURING OIL TEMPERATURE...193
        MEASURING OPERATING FORCE...194
        MEASURING AND ADJUSTING TRAVEL...195
      PROCEDURE FOR ADJUSTMENT OF TRAVEL DEVIATION...200
      TROUBLESHOOTING...206
        1.OUTLINE OF TROUBLESHOOTING FOR HST AND HST ELECTRONIC CONTROL SYSTEM...207
        2.HST TROUBLESHOOTING...210
          CONTENTS...210
            1.INTRODUCTION...211
            2.ASSUMPTIONS WHEN TROUBLESHOOTING...211
            3.PRECAUTIONS REGARDING DIRT AND CONTAMINATION IN OIL...211
            4.TROUBLESHOOTING TOOLS AND REPLACEMENT PARTS FOR TROUBLESHOOTING...211
            5.PRECAUTIONS FOR UNIT EXCHANGE...212
            6.TROUBLESHOOTING...213
              H-1 MACHINE DOES NOT MOVE FORWARD OR IN REVERSE...213
              H-2 MACHINE MOVES IN ONE DIRECTION (FORWARD OR REVERSE) BUT NOT IN OTHER DIRECTION...215
              H-3 MACHINE MOVES EVEN WHEN SPEED CONTROL LEVER IS IN NEUTRAL...216
              H-4 MACHINE DEVIATES GRADUALLY...216
              H-5 MACHINE DEVIATES SHARPLY...219
              H-6 TRACKS COUNTERROTATE...222
              H-7 MACHINE MOVES IN OPPOSITE DIRECTION...222
              H-7' WHEN STARTING ON LEVEL GROUND...223
              H-8 MACHINE MOVES SUDDENLY WHEN STARTING...223
              H-9 WHEN MACHINE STARTS, FRONT OF MACHINE WAVERS SLIGHTLY...224
              H-10 EXCESSIVE TIME LAG WHEN STARTING...225
              H-11 POOR ACCELERATION...225
              H-12 DIFFICULT TO TURN...226
              H-13 MACHINE TURNS SHARPLY INSTEAD OF GRADUALLY...227
              H-14 MACHINE TURNS IN OPPOSITE DIRECTION...227
              H-15 MACHINE DOES NOT RETURN TO STRAIGHT LINE...227
              H-16 MACHINE OVERSTEERS...228
              H-17 MACHINE DOES NOT SLOW DOWN SMOOTHLY...229
              H-18 MACHINE DEVIATES WHEN SLOWING DOWN...230
              H-19 MACHINE CANNOT BE CONTROLLED ON DOWNHILL SLOPES...231
              H-20 MACHINE STOPS SUDDENLY...231
              H-21 MACHINE LACKS POWER (MACHINE CANNOT TRAVEL AT MAXIMUM SPEED.)...232
              H-22 MACHINE LACKS POWER (ENGINE STALLS.)...233
              H-23 EXCESSIVE NOISE FROM HST...234
              H-24 HST OIL TEMPERATURE RISES TOO HIGH...235
    23 DISASSEMBLY AND ASSEMBLY...236
      DAMPER ASSEMBLY...237
        REMOVAL...237
        INSTALLATION...238
      TORQUE SPLITTER ASSEMBLY...239
        REMOVAL...239
        INSTALLATION...242
        DISASSEMBLY...245
        ASSEMBLY...248
      HST ASSEMBLY...251
        REMOVAL...251
        INSTALLATION...255
      HST UNIT...261
        DISASSEMBLY...261
        ASSEMBLY...278
      HST PUMP SERVO VALVE ASSEMBLY...333
        REMOVAL...333
        INSTALLATION...333
      ASSIST VALVE ASSEMBLY...334
        REMOVAL...334
        INSTALLATION...335
        DISASSEMBLY...336
        ASSEMBLY...338
      NEUTRAL BYPASS VALVE ASSEMBLY...340
        DISASSEMBLY...340
        ASSEMBLY...340
      HST MOTOR SERVO VALVE ASSEMBLY...341
        REMOVAL...341
        INSTALLATION...341
      CHARGING, SERVO PUMP ASSEMBLY...342
        REMOVAL...342
        INSTALLATION...342
      CHARGE FILTER BYPASS VALVE ASSEMBLY...343
        REMOVAL...343
        INSTALLATION...343
        DISASSEMBLY...344
        ASSEMBLY...344
      BRAKE CONTROL VALVE ASSEMBLY...345
        REMOVAL...345
        INSTALLATION...346
        DISASSEMBLY...347
        ASSEMBLY...349
      FINAL DRIVE ASSEMBLY...352
        REMOVAL...352
        INSTALLATION...354
        DISASSEMBLY...356
        ASSEMBLY...367
    24 MAINTENANCE STANDARD...375
      DAMPER...376
      TORQUE SPLITTER...377
      CHARGING PUMP AND SERVO PUMP...378
      BYPASS VALVE FOR CHARGING FILTER...379
      BRAKE...380
      FINAL DRIVE...381
  30 UNDERCARRIAGE...383
    31 STRUCTURE AND FUNCTION...383
      TRACK GROUP...384
      RECOIL SPRING...385
      IDLER...386
      CARRIER ROLLER...387
      TRACK ROLLER...388
      TRACK...389
      SUSPENSION...390
    33 DISASSEMBLY AND ASSEMBLY...392
      TRACK FRAME ASSEMBLY...393
        REMOVAL...393
        INSTALLATION...394
      RECOIL SPRING ASSEMBLY...395
        REMOVAL...395
        INSTALLATION...396
        DISASSEMBLY...397
        ASSEMBLY...398
      IDLER ASSEMBLY...399
        REMOVAL...399
        INSTALLATION...399
      TRACK ROLLER ASSEMBLY...400
        REMOVAL...400
        INSTALLATION...400
      CARRIER ROLLER ASSEMBLY...401
        REMOVAL...401
        INSTALLATION...401
      TRACK SHOE ASSEMBLY...402
        REMOVAL...402
        INSTALLATION...404
        ADJUSTING TENSION...406
      PIVOT SHAFT ASSEMBLY...407
        REMOVAL...407
        INSTALLATION...408
    34 MAINTENANCE STANDARD...409
      TRACK FRAME...410
      RECOIL SPRING...411
      IDLER...412
      TRACK ROLLER...414
      CARRIER ROLLER...416
      MEASURING PROCEDURE OF ROLLERS...417
      TRACK SHOE...419
      MEASURING PROCEDURE OF TRACK...421
      SUSPENSION...423
  60 HYDRAULIC SYSTEM...425
    61 STRUCTURE AND FUNCTION...425
      GENERAL...426
      HYDRAULIC CIRCUIT SYSTEM...428
      HYDRAULIC CONTROL...430
      HYDRAULIC AND UNLOADER PUMPS...431
      BUCKET CONTROL VALVE...432
      UNLOADER VALVE...437
      HYDRAULIC TANK...440
      HYDRAULIC CYLINDER...441
    62 TESTING AND ADJUSTING...442
      STANDARD VALUE TABLE...443
      TESTING AND ADJUSTING HYDRAULIC PRESSURE...444
      MEASURING HYDRAULIC OIL TEMPERATURE...445
      TESTING AND ADJUSTING TRAVEL AND OPERATING FORCE OF CONTROL LEVER...445
      MEASURING HYDRAULIC DRIFT OF WORK EQUIPMENT...446
      ADJUSTING ELECTRIC POSITIONER...447
    63 DISASSEMBLY AND ASSEMBLY...448
      MAIN CONTROL VALVE, PLATE ASSEMBLY (SERIAL NO.1001-1399)...449
        REMOVAL...449
        INSTALLATION...450
      MAIN CONTROL VALVE, PLATE ASSEMBLY (SERIAL NO.1400 AND UP)...451
        REMOVAL...451
        INSTALLATION...452
      MAIN CONTROL VALVE ASSEMBLY...453
        REMOVAL...453
        INSTALLATION...455
      RIPPER CONTROL VALVE ASSEMBLY...456
        REMOVAL...456
        INSTALLATION...456
      MAIN CONTROL VALVE ASSEMBLY...457
        DISASSEMBLY...457
        ASSEMBLY...459
      UNLOADER VALVE ASSEMBLY...461
        REMOVAL...461
        INSTALLATION...461
        DISASSEMBLY...463
        ASSEMBLY...464
      HYDRAULIC PUMP, UNLOADER PUMP ASSEMBLY...465
        REMOVAL...465
        INSTALLATION...465
      DUMP CYLINDER ASSEMBLY...466
        REMOVAL...466
        INSTALLATION...466
      LIFT CYLINDER ASSEMBLY...467
        REMOVAL...467
        INSTALLATION...468
      HYDRAULIC CYLINDER ASSEMBLY...469
        DISASSEMBLY...469
        ASSEMBLY...471
    64 MAINTENANCE STANDARD...474
      HYDRAULIC CONTROL VALVE...475
      UNLOADER VALVE...477
      HYDRAULIC AND UNLOADER PUMPS...479
      DUMP CYLINDER...480
      LIFT CYLINDER...481
  70 WORK EQUIPMENT...482
    71 STRUCTURE AND FUNCTION...482
      BUCKET LINK...483
      BUCKET CONTROL...485
      BUCKET...487
    73 DISASSEMBLY AND ASSEMBLY...488
      WORK EQUIPMENT ASSEMBLY...489
        REMOVAL...489
        INSTALLATION...490
    74 MAINTENANCE STANDARD...491
      BUCKET LINK...492
      BUCKET...494
  80 ELECTRIC AND ELECTRONIC SYSTEM...495
    81 STRUCTURE AND FUNCTION...495
      OUTLINE OF ELECTRIC AND ELECTRONIC SYSTEMS...496
      HST CONTROL SYSTEM...498
      SELF-CHECK FUNCTION OF HST CONTROL SYSTEM...502
      HST CONTROLLER...503
      POTENTIOMETER...504
      ENGINE SPEED SENSOR...505
      ELECTRONIC MONITORING SYSTEM...507
      WIRING DIAGRAM FOR CAB...520
      ELECTRIC CIRCUIT...521
    82 TESTING AND ADJUSTING...522
      OUTLINE OF TROUBLESHOOTING...523
      WAY OF USING TROUBLESHOOTING TABLES...524
      PRECAUTIONS WHEN TROUBLESHOOTING...525
      ELECTRICAL AND ELECTRONIC EQUIPMENT FOR D66S-1...528
      TROUBLESHOOTING FOR MONITOR PANEL...535
        1.CHECK THE FOLLOWS BEFORE STARTING TROUBLESHOOTING...535
        2.WIRING DIAGRAM AS TO MONITOR PANEL...536
        3.CONNECTOR NUMBERS FOR MONITOR PANEL...537
        4.METHOD OF REMOVING MONITOR PANEL BOX...540
        5.TROUBLESHOOTING CHART FOR MONITOR PANEL...541
        6.TROUBLESHOOTING...542
      TROUBLESHOOTING OF HST ELECTRONIC CONTROL SYSTEM...567
        1.OUTLINE...567
        2.SELF-CHECK FUNCTION BY MONITOR PANEL...570
        3.TROUBLESHOOTING OF HST ELECTRONIC CONTROL SYSTEM BY USING ATESTER...574
          CONTENTS...574
            1.TROUBLESHOOTING TOOLS...575
            2.TROUBLESHOOTING ...577
              A.IN CASE THAT SELF-CHECK FUNCTION ON THE MONITOR PANEL ("HST ELECTRONIC SYSTEM MONITOR 1","HST ELECTRONIC SYSTEM MONITOR 2","HST OIL PRESSURE MONITOR","WARNING LAMP","ALARM BUZZER") IS DISPLAYED...577
                T-1 DROP IN HST CHANGE PRESSURE...577
                T-2 NO SUPPLY OF ELECTRIC POWER TO HST CONTROLLER...579
                T-3 BREAKDOWN IN SPEED CONTROL LEVER SYSTEM...582
                T-4 BREAKDOWN IN PEDAL SYSTEM...588
                T-5 BREAKDOWN IN HST SERVO SYSTEM (SOLENOID VALVE)...590
                T-6 BREAKDOWN IN THE FUEL CONTROL LEVER AND ENGINE SPEED SENSOR...592
                T-7 BREAKDOWN IN STRAIGHT TRAVEL COMPENSATION SYSTEM...596
              B.IN CASE THAT DISPLAY OF MONITOR PANEL IS NORMAL, BUT MACHINE MOVEMENT IS ABNORMAL...598
                T-8 MACHINE DOES NOT MOVE EITHER FORWARD OR IN REVERSE...598
                T-9 EITHER FORWARD OR REVERSE WORKS...602
                T-10 MACHINE STOPS WHEN TRAVELING WITH NO LOAD...605
                T-11 MACHINE TRAVELS STRAIGHT, BUT THERE IS A PROBLEM WITH MACHINE SPEED...608
                T-12 WHILE TRAVELING, ONE SIDE STOPS MOVING...609
                T-13 WHILE TRAVELING, ONE SIDE IS SLOWER OR FASTER THAN THE OTHER (MACHINE DEVIATES)...611
      HOW TO INSTALL THE POTENTIOMETER...612
    83 DISASSEMBLY AND ASSEMBLY...614
      ELECTRONIC CONTROLLER ASSEMBLY, MONITOR ASSEMBLY...615
        REMOVAL...615
        INSTALLATION...617
  90 OTHERS...619
    91 STRUCTURE AND FUNCTION...619
      ROPS CAB...620
      AIR CONDITIONER ASSEMBLY...621
      AIR CONDITIONER PIPING...622
    93 DISASSEMBLY AND ASSEMBLY...623
      OPERATOR'S CAB, FRAME ASSEMBLY (SERIAL NO.1001-1399)...624
        REMOVAL...624
        INSTALLATION...625
      OPERATOR'S CAB, FRAME ASSEMBLY (SERIAL NO.1400 AND UP)...626
        REMOVAL...626
        INSTALLATION...627
SEBMU1440102 - Bulldozer D68E-1, D68P-1 Shop Manual (SN1001&up)...628