Complete workshop repair & service manual with electrical wiring diagrams for Caterpillar 120H & 135H Motor Graders. It's the same service manual used by dealers that guaranteed to be fully functional and intact without any missing page.

This Caterpillar 120H & 135H Motor Graders 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.

MANUAL LIST:
RENR1416 - Specifications (120H & 135H Motor Graders Air System & Brakes)
RENR1431 - Schematic (120H Motor Grader ES Version Hydraulic Systems)
RENR1439 - Schematic (120H Motor Grader (ES Version) Electrical System)
SENR6984 - Schematic (120H (ES Version) Motor Grader Electrical System)
SENR6994 - Specifications (120H & 135H Motor Graders Power Train)
SENR8523 - Specifications (120H & 135H Motor Graders Air System & Brakes)
SENR8538 - Disassembly & Assembly (Supplement for 120H & 135H Motor Graders - 3116 Engine)
SENR8543 - Disassembly & Assembly (120H & 135H Motor Graders Power Train)
SENR8544 - Disassembly & Assembly (120H & 135H Motor Graders Machine System)
SENR8557 - Specifications (120H Motor Grader Hydraulic & Steering System)
SENR8592 - Schematic (120H ES Version Motor Grader Hydraulic Systems)
SENR9059 - Specifications (120H, 12H, 135H, 140H, 143H, 14H, 160H, 163H & 16H Motor Graders Secondary Steering System)
SENR9059 - Systems Operation (120H, 12H, 135H, 140H, 143H, 14H, 160H, 163H & 16H Motor Graders Secondary Steering System)
SENR9059 - Testing & Adjusting (120H, 12H, 135H, 140H, 143H, 14H, 160H, 163H & 16H Motor Graders Secondary Steering System)
SENR9102 - Schematic (120H ES Version Motor Grader Hydraulic Systems)
SENR9157 - Specifications (120H & 135H Motor Graders Power Train)
SENR9179 - Specifications (120H & 135H Motor Graders Hydraulic & Steering System)
RENR1426 - Schematic (120H & 135H Motor Grader Standard Version Electrical System).pdf
RENR1440 - Schematic (120H & 135H Motor Grader Standard Version Electrical System).pdf
SENR8570 - 120H & 135H Standard Versions Motor Graders Hydraulic System.pdf
...

EXCERPT:
1. Remove plug (1) and drain the oil from the circle drive housing in a suitable container for storage or disposal. The capacity of the circle drive housing is 7 L (1.8 gal U.S.). Install plug (1).
2. Bend lock (2) away from nut (3).
3. Remove nut (3), lock (2), spacer (4) and the O-ring seal from circle drive shaft (7).
4. Remove nuts (6) and washers from the long studs of the circle drive housing.
5. Install Tooling (A) and a hoist to the circle drive housing.
6. Remove bolts (8) and the spacers that hold the circle drive housing to the circle draw bar.
7. Lift the circle drive enough in order to remove pinion gear (5) from shaft (7) and from engagement with the circle. Remove the circle drive from the circle. The weight of the circle drive is 45 Kg (100 lb).
8. Remove the Duo-Cone seal from the pinion.
Install Circle Drive
...

RENR1416 - Specifications (120H & 135H Motor Graders Air System & Brakes)...1
  Air Compressor...2
  Air Compressor Governor...4
  Air Tank...5
  Relief Valve (Air Tank)...6
  Solenoid Valve (Air Horn)...7
  Air Horn...9
  Air Dryer...11
  Pressure Switch (Low Brake Air)...13
  Pressure Switch (Brake Air) (Stop Lamp)...14
  Front Wiring...15
  Service Brake Control...17
  Air Control Valve (Parking Brake)...20
  Check Valve (Parking Brake Release)...21
  Solenoid Valve (Parking Brake)...22
  Pressure Switch (Brake Air) (Parking Brake)...23
  Service Brakes...24
  Parking Brake...27
RENR1426 - Schematic (120H & 135H Motor Grader Standard Version Electrical System)...29
  Features...29
  Cover Page...30
  Information...0
    Component Location...31
    Connector Location...32
    CID/MID/FMI...33
    Specifications And Related Manuals...34
    Wire Description...35
    Electrical Symbols...36
  Schematic...37
  Machine View...0
    Machine Harness Connector And Component Locations...38
RENR1431 - Schematic (120H Motor Grader ES Version Hydraulic Systems)...39
  Main...40
RENR1439 - Schematic (120H Motor Grader (ES Version) Electrical System)...42
  Main...43
  Collage...45
RENR1440 - Schematic (120H & 135H Motor Grader Standard Version Electrical System)...55
  Features...55
  Cover Page...56
  Information...0
    Component Location...57
    Connector Location...58
    CID/MID/FMI...59
    Specifications And Related Manuals...60
    Electrical Symbols...61
  Schematic...62
  Machine View...0
    Machine Harness Connector And Component Locations...63
SENR6984 - Schematic (120H (ES Version) Motor Grader Electrical System)...64
  Main...65
  Collage...67
SENR6994 - Specifications (120H & 135H Motor Graders Power Train)...94
  Magnetic Screen (Transmission)...95
  Gear Pump (Transmission Charging and Scavenge)...97
  Transmission Oil Lines...99
  Oil Filter (Power Train)...100
  Governor Control...103
  Clutch Control (Modulation)...106
  Transmission Case...113
  Transmission...115
  Transmission Control Valve...128
  Selector and Pressure Control Valve...133
  Pressure Switch (Transmission Modulation)...146
  Solenoid Valve (Transmission Clutch)...149
  Speed Sensor (Transmission Output)...152
  Temperature Sensor (Transmission Oil)...153
  Drive Shaft...154
  Differential and Bevel Gear...155
  Differential...162
  Solenoid Valve (Differential Lock)...164
  Final Drive...168
  Tandem and Cover...170
  Drive Chain...172
  Wheel Group...174
  Solenoid Valve (Centershift Lock)...176
  Case and Frame...177
  Rollover Protective Structure (ROPS) - If Equipped SMCS - 7325...179
  Window Wipers...181
  Window Washer...183
  Air Conditioner...184
SENR8523 - Specifications (120H & 135H Motor Graders Air System & Brakes)...186
  Air Compressor Governor...187
  Air Tank...189
  Relief Valve (Air Tank)...190
  Solenoid Valve (Air Horn)...191
  Air Horn...193
  Air Dryer...195
  Pressure Switch (Low Brake Air)...197
  Pressure Switch (Brake Air) (Stop Lamp)...198
  Front Wiring...200
  Service Brake Control...202
  Air Control Valve (Parking Brake)...205
  Check Valve (Parking Brake Release)...206
  Solenoid Valve (Parking Brake)...207
  Pressure Switch (Brake Air) (Parking Brake)...209
  Service Brakes...210
  Parking Brake...213
SENR8538 - Disassembly & Assembly (Supplement for 120H & 135H Motor Graders - 3116 Engine)...215
  Batteries...216
  Batteries & Battery Boxes...218
  Exhaust Pipe Assembly...221
  Prescreener Assembly...222
  Hood...223
  Air Cleaner Group...225
  Muffler...228
  Turbocharger...229
  Alternator...231
  Fan Spider Assembly...233
  Fan Drive...235
  V-Belts...239
  Electric Starting Motor...240
  Air Compressor...241
  Air Conditioning Compressor...244
  Engine Oil Filler Group...246
  Engine Oil Filter & Oil Filter Base...247
  Engine Oil Cooler...251
  Transmission Oil Cooler...254
  Fuel Priming Pump...256
  Fuel Filter & Fuel Filter Base...257
  Water Separator Group...259
  Radiator...261
  Water Temperature Regulator...266
  Water Pump...268
  Water Pump Drive...274
  Pump Group Drive Shaft...277
  Speedometer & Tachometer Sensor...279
  Engine...280
SENR8543 - Disassembly & Assembly (120H & 135H Motor Graders Power Train)...292
  Conventional Duo-Cone Seals...293
  Rear Tires & Rims...300
  Drive Chains...302
  Brake & Wheel Spindle Housings...306
  Differential Drive Shaft...315
  Parking Brake...317
  Tandem Drive Housings...326
  Drive Sprockets...328
  Final Drives...331
  Transmission Speed Sensor...342
  Transmission Oil Filter...344
  Transmission Oil Filter Base...346
  Transmission Magnetic Screen Filter Group...348
  Transmission Magnetic Screen Filter Base...350
  Transmission Oil Pump...352
  Transmission Oil Cooler...359
  Transmission Hydraulic Control Valve...362
  Transmission...386
  Differential & Bevel Gear...433
  Differential Lock Control Valve...452
  Transmission & Transmission Hydraulic Control Valve; Testing and Adjusting...454
SENR8544 - Disassembly & Assembly (120H & 135H Motor Graders Machine System)...467
  Conventional Duo-Cone Seals...469
  Front Tires & Rims...476
  Front Wheel Spindles...478
  Front Wheel Spindle Housings...483
  Steering Metering Pump...489
  Steering Cylinders...504
  Steering Tie Rod...511
  Steering Hydraulic Accumulator...513
  Wheel Lean Arms...516
  Wheel Lean Bar...523
  Wheel Lean Cylinder...526
  Front Axle Group...532
  Blade Lift Accumulators...538
  Blade Lift Cylinders...541
  Ball & Socket Joint Inserts...547
  Blade Lift Arms...549
  Centershift Lock...557
  Blade Lift Bar_Centershift Lock Bar...562
  Centershift Lock Control Valve...565
  Centershift Lock Bar Bushings...569
  Blade Side Shift Cylinder...572
  Blade Centershift Cylinder...581
  Blade Tip Cylinder...587
  Swivel Group...594
  Blade...600
  Blade Assembly...604
  Circle...610
  Circle Draw Bar...614
  Circle Drive Motor...622
  Circle Drive...630
  Seat Assembly...643
  Cab...645
  Hydraulic Oil Tank Filter...654
  Hydraulic Oil Tank...656
  Implement Pump Drive...660
  Implement Hydraulic Pump...662
  Implement Control Valves...678
  Combination Valve...691
  Compensator Valve...700
  Air Dryer Group...708
  Parking Brake Control Air Valve Assembly...710
  Parking Brake Solenoid Valve...715
  Brake Control Air Valve...716
  Differential Lock Actuator Valve...723
  Fuel Tank...726
  Articulation Cylinders...731
  Supplemental Steering...739
  Main Frames...742
  Pivot Pin Bearings...756
  Rear Bumper...761
  Ripper Lift Cylinder...764
  Ripper...771
  Air Tank...787
  Scarifier Lift Cylinder...790
  Scarifier...796
SENR8557 - Specifications (120H Motor Grader Hydraulic & Steering System)...805
  Piston Pump (Hydraulic and Steering)...807
  Pump Control Valve (Pressure and Flow Compensator)...813
  Steering Control...815
  Pump Drive Shaft...816
  Metering Pump (Steering)...817
  Hydraulic Tank Mounting...820
  Hydraulic Tank and Filter...821
  Operator Console...823
  Valve and Linkage Group...826
  Steering Accumulator...828
  Control Valve (Blade Tip)...829
  Control Valve (Blade Lift)...832
  Circle Drive Control Valve...834
  Articulation Control Valve...836
  Control Valve (Scarifier)...838
  Control Valve (Wheel Lean)...841
  Ripper Control Valve...843
  Centershift Control Valve...846
  Sideshift Control Valve...849
  Scarifier Relief Valve...851
  Blade Tip Relief Valve...853
  Sideshift Relief Valve...855
  Blade Lift Relief Valve...857
  Ripper Relief Valve...859
  Relief Valve (Implement)...861
  Combination Valve...862
  Solenoid Valve (Centershift Lock)...866
  Relief Valve (Steering)...867
  Relief Valve (Signal)...869
  Articulation Cylinder...870
  Blade Lift Cylinder...872
  Blade Tip Cylinder...874
  Centershift Cylinder...876
  Ripper Lift Cylinder...878
  Ripper Cylinder and Lines...880
  Scarifier Cylinder...881
  Sideshift Cylinder...883
  Steering Cylinder...885
  Wheel Lean Cylinder...887
  Articulation Cylinder Mounting...889
  Blade Lift Cylinder Mounting...891
  Wheel Lean Cylinder and Mounting...892
  Centershift Cylinder Mounting...893
  Articulated Hitch...894
  Scarifier...896
  Swivel...899
  Circle Drive...900
  Circle Drive - Slip Clutch...902
  Blade Lift...907
  Circle...909
  Drawbar...911
  Front Axle...915
SENR8570 - 120H & 135H Standard Versions Motor Graders Hydraulic System...921
SENR9102 - Schematic (120H ES Version Motor Grader Hydraulic Systems)...923
  Main...924
SENR9157 - Specifications (120H & 135H Motor Graders Power Train)...926
  Magnetic Screen (Transmission)...927
  Gear Pump (Transmission Charging and Scavenge)...929
  Transmission Oil Lines...931
  Oil Filter (Power Train)...933
  Governor Control...936
  Clutch Control (Modulation)...939
  Transmission Case...946
  Transmission...948
  Transmission Control Valve...961
  Selector and Pressure Control Valve...966
  Pressure Switch (Transmission Modulation)...980
  Solenoid Valve (Transmission Clutch)...984
  Speed Sensor (Transmission Output)...987
  Drive Shaft...989
  Differential and Bevel Gear...990
  Differential...997
  Solenoid Valve (Differential Lock)...999
  Final Drive...1003
  Tandem and Cover...1005
  Drive Chain...1007
  Wheel Group...1009
  Solenoid Valve (Centershift Lock)...1011
  Case and Frame...1012
  Rollover Protective Structure (ROPS) - If Equipped SMCS - 7325...1014
  Window Wipers...1016
  Window Washer...1018
  Air Conditioner...1019
SENR9179 - Specifications (120H & 135H Motor Graders Hydraulic & Steering System)...1021
  Hydraulic Tank and Filter...1023
  Hydraulic Tank Mounting...1025
  Piston Pump (Hydraulic and Steering)...1026
  Pump Control Valve (Pressure and Flow Compensator)...1032
  Pump Drive Shaft...1034
  Steering Control...1035
  Metering Pump (Steering)...1036
  Accumulator (Steering)...1039
  Accumulator (Blade Cushion)...1040
  Solenoid Valve (Blade Cushion)...1042
  Valve and Linkage Group...1044
  Articulation Control Valve...1048
  Control Valve (Blade Lift)...1050
  Blade Lift Control Valve...1053
  Control Valve (Blade Tip)...1056
  Circle Drive Control Valve...1059
  Ripper Control Valve...1061
  Control Valve (Scarifier)...1064
  Sideshift Control Valve...1067
  Control Valve (Snow Plow_Dozer Lift)...1069
  Control Valve (Wheel Lean)...1072
  Relief Valve (Blade Lift)...1074
  Relief Valve (Blade Tip)...1076
  Relief Valve (Implement)...1078
  Relief Valve (Ripper)...1079
  Relief Valve (Scarifier)...1083
  Relief Valve (Sideshift)...1085
  Relief Valve (Signal)...1087
  Relief Valve (Snow Plow_Dozer Lift)...1088
  Relief Valve (Steering)...1090
  Articulation Cylinder...1092
  Blade Lift Cylinder...1096
  Blade Tip Cylinder...1098
  Centershift Cylinder...1100
  Ripper Lift Cylinder...1102
  Ripper Cylinder and Lines...1104
  Scarifier Cylinder...1106
  Sideshift Cylinder...1108
  Steering Cylinder...1110
  Wheel Lean Cylinder...1114
  Articulation Cylinder Mounting...1116
  Blade Lift Cylinder Mounting...1118
  Centershift Cylinder Mounting...1119
  Wheel Lean Cylinder and Mounting...1120
  Centershift Lock...1121
  Solenoid Valve (Centershift Lock)...1123
  Operator Console...1124
  Articulated Hitch...1127
  Articulation Position Sender...1129
  Blade Lift...1130
  Gerotor Motor (Circle Drive)...1132
  Circle...1133
  Circle Drive...1135
  Drawbar...1142
  Front Axle...1146
  Scarifier...1152
  Swivel...1155