INTERACTIVE SCHEMATIC
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Cover Page
Information
Schematic
Machine Views
Component Table
Tap Table
Fluid Power Symbols
Electrical Symbols
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Rear Frame
Tap Views
Features
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Bookmarks
X
EC-C3
EC-C2
E-C60
EC-C1
E-C61
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©
2004 Caterpillar, All Rights Reserved
Printed in U.S.A.
Hydraulic System
AZX1-UP
992G Wheel Loader
Hydraulic System
RENR6324
May 2004
Page 1 of 2
COMPONENT LOCATION
Description
Part
Number
Machine
Location
Schematic
Location
Accumulator - Ride Control 219-7981 1 D-10
Accumulator - Brake Supply 220-2718 4 D-4
Brake Gp - Foot 112-2273 16 G-5
Brake Gp - Parking 8R-5518 16 G-3
Cooler 190-7624 8 C-11
Cooler - Steering Pilot Oil 190-7625 9 D-6
Cooler - Axle Oil Cooler 115-4831 8 B-2
Cylinder - Lift 162-1523 5 F-14
Cylinder - Lift 162-1522 5 F-12
Cylinder - Tilt 167-7996 6 F-13
Cylinder - Steer (Right) 112-8208 4 F-9
Cylinder - Steer (Left) 112-8208 4 F-8
Filter - Pilot Oil 115-2129 9 C-15
Filter - Case Drain 166-4647 8 C-11
Filter - Case Drain 166-4647 7 B-11
Filter - Case Drain 166-4647 7 B-13
Filter - Case Drain 166-4647 4 C-6
Filter - Case Drain 166-4647 4 C-5
Filter - Steering Pilot Oil 115-2129 4 C-5
Filter - Rear Axle Oil 230-3633 17 B-3
Filter - Front Axle Oil 230-3633 17 C-3
Manifold 113-9502 10 C-12
Motor Gp - Fan Drive 159-7166 8 C-11
Pump Gp - Implement Pilot 136-3965 7 B-15
Pump Gp - Torque Control (Var Disp) 216-4825 7 B-14
Pump Gp - Implement 112-5381 7 B-13
Pump Gp - Fan Drive/Cooling 186-2821 7 B-11
Pump Gp - Steering 216-4826 4 C-7
Pump Gp - Steering Pilot 136-3965 4 B-5
Pump Gp - Brake Supply 164-5486 7 C-5
Pump Gp - Axle Oil Cooling 229-0659 8 C-2
Pump Gp - Secondary Steering 101-4007 4 D-6
Screen - Implement 174-4502 7 C-13
Screen - Implement 174-4502 8 C-11
Screen - Fan Drive Charge 196-4747 8 B-10
Screen - Implement 174-4502 4 C-7
Sensor Gp - Brake Pressure (VIMS only) 112-9779 16
E-3
Sensor Gp - Front Axle Oil Temp 100-3055
13
G-4
Page 2 of 2
COMPONENT LOCATION
Page 1 of 2
Switch - Pressure 117-7773
10
C-15
Switch - Pressure 117-7773 7 B-13
Switch - Pressure 117-7773 7 B-12
Switch - Pressure 117-7773 7 B-11
Switch - Pressure 117-7773 8 C-11
Switch - Pressure 117-7773 9 C-5
Switch - Pressure 117-7773 4 C-5
Switch - Pressure 117-7773 4 C-7
Switch - Brake Low Pressure 3E-7693 14 F-4
Switch - Parking Brake/Trans Override 3E-5181 14 G-3
Switch - Parking Brake Pressure 100-3055 14 G-2
Tank Gp - Implement Oil 139-2763 11 B-12
Tank Gp - Air Expansion 220-2771 4 B-8
Tank Gp - Steering and Brake 197-1401 12 B-6
Valve Gp - Implement Control 185-1439 3 E-15
Valve Gp - Manual Lower 112-1817 1 D-15
Valve Gp - Pump Torque Signal Solenoid 196-5862 15 D-15
Valve Gp - Relief 114-4672 10 C-15
Valve Gp - Cooler Bypass 6E-1454 8 C-11
Valve Gp - Cooler Drain 8T-6097 8 C-12
Valve Gp - Ride Control 9T-9552 1 D-11
Valve Gp - Ride Control Solenoid 152-8340 2 D-10
Valve Gp - Fan Speed 191-8735 7 B-10
Valve Gp - Steering Pilot
143-2855 4
C-9
Valve Gp - Steering Neutralizer Right
Turn
146-7571 9
C-9
Valve Gp - Steering Neutralizer Left Turn 146-7571 9 C-8
Valve Gp - Check Steering Neutralizer 111-7775 9 D-9
Valve Gp - Steering Standard 126-1357 13 E-7
Valve Gp - Secondary Steering Selector 6E-3078 14 D-7
Valve Gp - Breaker Relief 133-1963 4 B-7
Valve Gp - Breaker Relief 133-1963 4 B-8
Valve Gp - Cooler Drain 8T-6097 4 D-6
Valve Gp - Relief 114-4672 4 D-5
Valve Gp - Check Rear Axle Oil 168-0360 17 B-2
Valve Gp - Check Front Axle Oil
168-0360
17
B-2
Description
Part
Number
Machine
Location
Schematic
Location
TAP LOCATION
Tap
Number
Description
Schematic
Location
AA Variable Disp Pump (Torque Control) Relief Port C-12
BB Fixed Disp Pump (Implement) Relief Port C-13
CC Fan Speed Pressure Port C-10
DD Implement Pilot Pressure Port C-12
EE Tilt Cylinder Head End Pressure Port F-12
FF Tilt Cylinder Rod End Pressure Port (no tap) F-12
GG Lift Cylinder Head End Pressure Port F-14
HH Lift Cylinder Rod End Pressure Port F-14
II Ride Control Signal Pressure Port D-11
JJ Fan Drive Output Pressure Port B-11
KK Steering Pilot Supply Port D-6
LL Steering Pump Discharge C-7
MM Steering Cylinder (Right) F-9
NN Steering Cylinder (Left) F-8
SPECIFICATIONS AND RELATED MANUALS
Description Media Number
992G III Wheel Loader SEBP4013
Specifications: (Electrohydraulic System) SENR1366
Testing and Adjusting: (Electrohydraulic System) SENR1367
Specifications: (Steering System) SENR1348
Testing and Adjusting: (Steering System) SENR1373
Specifications: (Braking System) SENR1351
Testing and Adjusting: (Braking System) SENR1353
Schematic: (Electrical System) RENR6317
Parts Manual:
Machine System:
Electrical System:
FLUID POWER SYMBOLS
ONE POSITION
TWO POSITION
THREE POSITION
VENTED
PRESSURIZED
RETURN ABOVE FLUID LEVEL
RETURN BELOW FLUID LEVEL
LINES CROSSING LINES JOINING
TWO-WAY
THREE-WAY
FOUR-WAY
SPRING
CONTROL VALVES
RESTRICTION
LINE RESTRICTION
(FIXED)
2-SECTION PUMP
MAIN
AUX.
SPRING
(ADJUSTABLE)
VARIABILITY
LINE RESTRICTION
(VARIABLE)
LINE RESTRICTION
VARIABLE and PRESSURE
COMPENSATED
PRESSURE
COMPENSATION
PUMP: VARIABLE and
PRESSURE COMPENSATED
ENERGY TRIANGLES
HYDRAULIC PNEUMATIC
MEASUREMENT
PRESSURE
TEMPERATURE
FLOW
ROTATING SHAFTS
UNIDIRECTIONAL BIDIRECTIONAL
PUSH-PULL LEVER PEDALGENERAL MANUAL PUSH BUTTON SPRING
MANUAL CONTROL SYMBOLS
HYDRAULIC MOTORS
FIXED
DISPLACEMENT
VARIABLE DISPLACEMENT
NON-COMPENSATED
UNIDIRECTIONAL
BIDIRECTIONAL
HYDRAULIC PUMPS
FLUID STORAGE RESERVOIRS
CROSSING AND JOINING LINES
VALVE ENVELOPES
VALVE PORTS
BASIC COMPONENT SYMBOLS
FLUID CONDITIONER
PUMP or MOTOR
FIXED
DISPLACEMENT
VARIABLE DISPLACEMENT
NON-COMPENSATED
UNIDIRECTIONAL
BIDIRECTIONAL
VALVES
PILOT CONTROL SYMBOLS
RELEASED PRESSURE
EXTERNAL RETURN
INTERNAL RETURN
REMOTE SUPPLY PRESSURE
SIMPLIFIED
COMPLETE
INTERNAL
SUPPLY PRESSURE
ACCUMULATORS
SPRING LOADED GAS CHARGED
SOLENOID
or MANUAL
SOLENOID
and PILOT
SOLENOID and
PILOT or MANUAL
COMBINATION CONTROLS
SOLENOID
SERVO
THERMAL
DETENT
HYDRAULIC AND PNEUMATIC CYLINDERS
DOUBLE ACTINGSINGLE ACTING
BASIC
SYMBOL
SPRING
LOADED
CHECK VALVES
TWO
POSITION
INFINITE
POSITIONING
FLOW IN ONE
DIRECTION
FLOW ALLOWED IN
EITHER DIRECTION
THREE
POSITION
CROSS
FLOW
PARALLEL
FLOW
INTERNAL PASSAGEWAYS
NORMAL POSITION
A B
P T
A B
P T
SHIFTED POSITION
INFINITE POSITION
CONTROL VALVES
ATTACHMENT
MANUAL SHUTOFF
SHUTTLE PILOT
CONTROLLED
ELECTRICAL SYMBOLS
Hydraulic Symbols (Electrical)
325-AG135 PK-14
Circuit Identification
Number
Wire Color
Wire Gauge
Harness identification code
This example indicates
wire 135 in harness "AG".
325-PK-14
Wire Gauge
Wire Color
Circuit Number
Identification
Wire Number Identification Codes
Current Standard
Previous Standard
Electrical Schematic Example
Hydraulic Schematic Example
325-PK
Wire Color
Circuit Number
Identification
B
A
Wire
Wire
(EXAMPLE VALVE)
Current Standard
Transducer
(Fluid)
Transducer
(Gas / Air)
G
Generator
Electrical Wire
Pressure Switch
M
Electric Motor
Pressure Switch
(Adjustable)
Temperature Switch
Pressure
Symbol
Temperature
Symbol
Level
Symbol
Flow
Symbol
Electrical Symbols (Electrical)
T
1213
14
1
2
3
4
56
7
8
A
B
C
D
E
G
F
910
11
1213
14
15
3
4
56
7
8
1
2
A
C
D
E
G
B
F
15
9
10
11
HYDRAULIC CIRCUIT COLOR DESCRIPTIONS
Main Pump Output.
Pilot Pump Output.
Fan Drive Pump Output.
Steering Pump Output.
Steering Pilot Pump Output .
Brake Pump Output.
Supply Line
Drain/Return Line.
Torque Control Pump Output.
Steering Control Circuit.
Lift Cylinder Circuit.
Tilt Cylinder Circuit.
Brake Control System Circuit.
Axle Oil Cooling Pump Output.
Secondary Steering Pump Output.
LINE PATTERNS
Drain / Return Lines
Component Group
Pilot / Load Sensing Pressure
Pressure Line
Attachment
Air Line
CALLOUTS
Taps (Pressure, Sampling,Sensor) by letter
YY
VALVE GP
PRESSURE
REDUCING
6E-4286
(13) VALVE GP
STEERING
STANDARD
126-1357
VALVE GP
RELIEF
STEERING CYLINDER
CROSSOVER
6E-3985
VALVE GP
SHUTTLE
4T-1860
HS
PS
FLUID
SAMPLING
PORT
RIGHT
TURN
STEERING
CYLINDERS
STEER
WARNING
SWITCH
(3) VALVE GP
IMPLEMENT CONTROL
185-1439
VALVE GP
SOLENOID
PILOT
149-2610
VALVE GP
SHUTTLE
DEAD ENGINE
148-2341
(8) VALVE GP
COOLER BYPASS
6E-1454
(15) VALVE GP
SOLENOID
PUMP TORQUE
SIGNAL
196-5862
FLUID
SAMPLING
PORT
TILT
CYLINDER
HYDRAC
ON/OFF
E9
L0WER
RAISE
DUMP
RACKBACK
DUMP
RAISE
L0WER
E6
E7
E5
E4
RACKBACK
FAN SPEED
TORQUE
LEVEL
E1
E3
E8
E12
E13
E11
LIFT
CYLINDER
E14
LIFT
CYLINDER
(8) SCREEN
FAN DRIVE
CHARGE
196-4747
SENSOR GP
PRESSURE
FAN PUMP DISCHARGE
167-1709
SENSOR GP
PRESSURE
IMPLEMENT
143-9176
(7) SWITCH GP
PRESSURE
117-7773
(8) SWITCH GP
PRESSURE
117-7773
VALVE GP
RELIEF
TILT
117-0160
VALVE GP
RELIEF
TILT
117-0161
VALVE GP
RELIEF
LIFT
129-8293
(8) COOLER
190-7624
VALVE GP
RELIEF
LIFT
125-9349
(8)VALVE GP
COOLER DRAIN
8T-6097
(9) FILTER GP
PILOT
115-2129
(10) VALVE GP
RELIEF
114-4672
(6) CYLINDER GP
TILT
167-7996
(5) CYLINDER GP
LIFT
162-1523
(7) PUMP GP
FAN DRIVE
& COOLING
186-2821
(7) VALVE GP
FAN SPEED
191-8735
(4) TANK GP
AIR EXPANSION
220-2771
VALVE GP
BREAKER RELIEF
133-1963
(4) FILTER GP
CASE DRAIN
166-4647
SCREEN GP
174-4502
(4) FILTER GP
PUMP CASE
DRAIN
166-4647
SCREEN GP
174-4502
(4) ACCUMULATOR
BRAKE SUPPLY
220-2718
(7) PUMP GP
BRAKE SUPPLY
164-5486
(4) VALVE GP
RELIEF
114-4672
(14) VALVE GP
SECONDARY
STEERING
SELECTOR
6E-3078
(4) VALVE GP
COOLER DRAIN
8T-6907
(4) FILTER GP
STEERING
PILOT
115-2129
(9) COOLER GP
STEERING PILOT OIL
190-7625
(4) PUMP GP
STEERING PILOT
136-3965
(9) VALVE GP
CHECK
STEERING
NEUTRALIZER
111-7775
(9) VALVE GP
STEERING
NEUTRALIZER
LEFT TURN
146-7571
(4) VALVE GP
STEERING PILOT
143-2855
(4) PUMP GP
SECONDARY
STEERING
101-4007
VALVE GP
SECONDARY
STEERING
RELIEF
6E-3986
VALVE GP
SECONDARY
STEERING
DIVERTER
2U-7345
ACTUATOR GP
SOLENOID
180-9550
VALVE GP
RELIEF
STEERING
100-4335
AUTO
LUBE
RETURN
AUTO
LUBE
SUPPLY
(2) VALVE GP
SOLENOID
RIDE CONTROL
152-8340
(8) FILTER GP
PUMP CASE DRAIN
166-4647
AIR CONNECTION
TO IMPLEMENT TANK
(1) ACCUMULATOR
RIDE CONTROL
219-7981
(7) FILTER GP
CASE DRAIN
166-4647
(1) VALVE GP
RIDE CONTROL
9T-9552
(1) VALVE GP
MANUAL LOWER
112-1817
(7) PUMP GP
TORQUE CONTROL
216-4825
(7) PUMP GP
IMPLEMENT
112-5381
(10) MANIFOLD
113-9502
(8) MOTOR GP
FAN DRIVE
159-7166
STEM
FLOAT FUNCTION
100-6731
(4) PUMP GP
STEERING
216-4826
VALVE GP
RELIEF
IMPLEMENT PUMP
117-0159
VALVE GP
PRESSURE
DEAD ENGINE
6E-4286
VALVE GP
RELIEF
TORQUE PUMP
143-8912
(7) PUMP GP
IMPLEMENT PILOT
136-3965
(11) TANK GP
IMPLEMENT
HYDRAULIC OIL
139-2763
(7) SCREEN
IMPLEMENT
174-4502
HYDRAULIC SCHEMATIC
IMPLEMENT/FAN DRIVE
BRAKE SYSTEM SCHEMATIC
(17) FILTER GP
FRONT AXLE OIL
230-3633
(17) FILTER GP
REAR AXLE OIL
230-3633
(12) TANK GP
STEERING & BRAKE
HYDRAULIC OIL
197-1401
(4) SCREEN GP
174-4502
(9) VALVE GP
STEERING
NEUTRALIZER
RIGHT TURN
146-7571
(4) CYLINDER GP
STEERING (RIGHT)
112-8208
(10) SWITCH GP
PRESSURE
117-7773
(7) SWITCH GP
PRESSURE
117-7773
ACTUATOR GP
SOLENOID
179-8248
(5) CYLINDER GP
LIFT
162-1522
(8) SCREEN
IMPLEMENT
174-4502
ACTUATOR GP
SOLENOID
180-9550
ACTUATOR GP
SOLENOID
179-8248
(4) VALVE GP
BREAKER RELIEF
220-0812
(4) SWITCH GP
PRESSURE
117-7773
(4) SWITCH GP
PRESSURE
117-7773
RIDE CONTROL
VALVE GP
SECONDARY STEERING
ATTACHMENT
112-4597
VARIABLE DISP PUMP
RELIEF PRESSURE
TAP
FIXED DISP PUMP
RELIEF PRESSURE
TAP
IMPLEMENT
PILOT PRESSURE
TAP
THIS SCHEMATIC IS FOR THE 992G WHEEL LOADER
Part #: 230-1471 CHG 00
Part #: 229-3722 CHG 00 (Axle Oil Cooling System Schematic)
Part #: 138-4558 CHG 04 (Brake Control System Schematic)
(8) PUMP GP
AXLE OIL COOLING
229-0659
(17) VALVE GP
CHECK
FRONT AXLE OIL
168-0360
(17) VALVE GP
CHECK
REAR AXLE OIL
168-0360
(8) COOLER GP
2 SECTION
AXLE OIL
115-4831
REAR AXLE
FRONT AXLE
AXLE OIL COOLING
SYSTEM SCHEMATIC
REAR AXLE
FRONT AXLE
PARKING BRAKE TRANSMISSION
INTERLOCK OVERRIDE SW
STOPLAMP SW
THROTTLE LOCK DISCONNECT SW
IMPELLER CLUTCH PEDAL
POSITION SIGNAL
(TO TRANSMISSION CONTROL)
(13) SENSOR GP
FRONT AXLE OIL
TEMPERATURE
100-3055
(14) SWITCH GP
PARKING BRAKE
PRESSURE
100-3055
(14) SWITCH GP
BRAKE LOW
PRESSURE WARN
3E-7693
VALVE GP
TANDEM BRAKE
129-7673
(16) CONTROL GP
FOOT BRAKE
112-2273
(16) BRAKE GP
PARKING
8R-5518
(16) SENSOR GP
BRAKE PRESSURE
(VIMS ONLY)
112-9779
VALVE GP
BRAKE
100-8941
VALVE GP
CHECK
PARKING BRAKE
RETURN OIL
6E-5444
(14) SWITCH AS
PARKING BRAKE
/XMSN INTERLOCK
OVERIDE
3E-5181
HYDRAULIC SCHEMATIC
STEERING/BRAKE SUPPLY
SENSOR
REAR AXLE OIL
TEMPERATURE
100-3055
FAN SPEED
PRESSURE TAP
FAN DRIVE
OUTPUT PRESSURE
TAP
RIDE CONTROL
SIGNAL
PRESSURE TAP
TILT CYL
HEAD END
PRESSURE TAP
TILT CYL
ROD END
PRESSURE PORT
(NO TAP)
LIFT CYL
ROD END
PRESSURE TAP
LIFT CYL
HEAD END
PRESSURE TAP
STEERING PUMP
DISCHARGE
PRESSURE TAP
STEERING PILOT
SUPPLY TAP
RIGHT STEERING
CYLINDER PRESSURE
TAP
LEFT STEERING
CYLINDER PRESSURE
TAP
Components are shown installed on a fully operable machine with the key and engine
off and transmission shifter in neutral.
BRAKE
RETURN
LINE
REAR
BRAKE
SUPPLY
FRONT
BRAKE
SUPPLY
BRAKE
RETURN
LINE
REAR
BRAKE
SUPPLY
FRONT
BRAKE
SUPPLY
AIR CONNECTION
TO IMPLEMENT TANK
HH
GG
EE
FF
BB
AA
DD
II
CC
LL
KK
JJ
MM
NN
(4) CYLINDER GP
STEERING (LEFT)
112-8208
(9) SWITCH GP
PRESSURE
117-7773
(4) VALVE GP
BREAKER RELIEF
133-1963
(7) SWITCH GP
PRESSURE
117-7773
(7) FILTER GP
CASE DRAIN
166-4647
MACHINE COMPONENT LOCATION
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
VIEW ALL CALLOUTS
LEFT SIDE VIEW OF MACHINE
4
4
MACHINE TAP LOCATION
Tilt Cylinder Head End Pressure Tap (EE)
Tilt Cylinder Rod End Pressure Port-no Tap (FF)
Lift Cylinder Head End Pressure Tap (GG)
Lift Cylinder Rod End Pressure Tap (HH)
Pilot
Solenoid
717-BR
716-Wh
HH
GG
FF
EE
3
VIEW ALL CALLOUTS
RIDE CONTROL
Ride Control
Solenoid
976-OR
975-WH
SECTION A-A
II
1
1
1
VIEW ALL CALLOUTS
RIGHT SIDE VIEW OF MACHINE
Torque Control
Variable Disp Pump
Prop Solenoid
707-YL
716-WH
TOP VIEW OF MACHINE
Fan Speed
Solenoid
700-BU
799-BR
Fan Drive Output Pressure Tap (JJ)
Fan Drive Signal Pressure Tap (CC)
Variable Disp(Torque Control) Pump Pressure Relief Tap (AA)
Fixed Disp(Implement) Pump Pressure Relief Tap (BB)
Implement Pilot pump Pressure Relief Tap (DD)
JJ
DD
CC
BB
AA
10
8
7
7
7
7
7
VIEW ALL CALLOUTS
