INTERACTIVE SCHEMATIC
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Cover Page
Information
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Tap Table
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Electrical Symbols
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X
EC-C3
EC-C2
E-C60
EC-C1
E-C61
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980G Series II Wheel Loader
Hydraulic System
AWH1-UP
AXG1-UP
AYT1-UP
©
2003 Caterpillar, All Rights Reserved
Printed in U.S.A.
RENR6019-01
February 2003
Page 1 of 2
COMPONENT LOCATION
Description
Part
Number
Machine
Location
Schematic
Location
Valve Gp - Main Control * 114-2788 1 E-6
Valve Gp - Line Relief (Auxiliary Rod End) 4T-4934 2 D-6
Valve Gp - Line Relief (Auxiliary Head End) 4T-4162 3 D-6
Cylinder Gp - Tilt # 124-6228 5 E-5
Cylinder Gp - Lift 111-8181 6 E-4
Valve Gp - Shuttle (Ride Control) @ 141-1481 7 E-4
Valve Gp - Solenoid Ride Control @ 3E-8574 8 E-3
Accumulator As - Ride Control @ 138-1292 9 E-3
Brake Gp - Service Front 208-5972 10 E-3
Brake Gp - Service Rear 208-5974 11 E-3
Valve Gp - Control (Service Brake) 191-1265 12 E-2
Pedal As - Right 193-1448 13 E-2
Valve Gp - Check (Ride Control) @ 104-7108 14 E-4
Valve Gp - Relief (Ride Control) @ 159-8201 15 E-3
Brake Gp - Parking 4E-8525 16 E-1
Valve Gp - Main Relief 114-2789 17 D-7
Relief Valve Gp - Line Relief (Dump) 4T-4933 18 D-5
Valve Gp - Line Relief (Tilt Back) 9T-0818 19 D-5
Valve Gp - Check (Ride Control) 9T-3096 20 E-4
Accumulator Gp - Rear Service Brake 111-9040 21 D-2
Accumulator Gp - Front Service Brake 111-9040 22 D-3
Valve Gp - Accumulator Charging (Service Brakes) 172-6144 23 D-3
Brake Gp - Parking Actuator 154-8042 24 E-1
Switch As - Low Oil Pressure (Service Brake) 175-3244 25 D-2
Switch As - Pressure (Parking Brake) 174-4312 27 D-1
Filter Screen (Pilot Valve) 6E-5065 28 D-7
Valve Gp - Diverter Ride Control @ 115-9328 29 D-3
Valve Gp - Dead Battery Manual Lower 112-1817 31 C-7
Valve Gp - Pilot Oil Manifold 142-3998 32 C-6
Cylinder Gp - Steering 115-1371 33 C-3
Pump Gp - Pilot/Brake 113-7750 34 B-7
Motor Gp - Hydraulic Fan 161-8919 35 B-6
Page 2 of 2
COMPONENT LOCATION
Description
Part
Number
Machine
Location
Schematic
Location
Valve Gp - Control Electrohydraulic 191-8735 36 B-5
Valve Gp - Steering Pilot 173-0439 37 B-4
Screen Gp - Steering Filter 154-1883 38 B-4
Valve Gp - Steering Neutralizer 8J-1553 39 B-4
Valve Gp - Relief Steering Crossover 9T-7419 40 B-3
Valve Gp - Shuttle Steering 8J-6875 41 B-3
Valve Gp - Steering 166-8495 42 B-3
Valve Gp - Relief (Steering Back Up) 9T-7418 43 B-3
Valve Gp - Hydraulic Oil Cooler Bypass 130-5202 44 B-6
Cooler As - Hydraulic Oil 130-7955 45 B-6
Pump Gp - Transmission 136-0529 46 B-7
Pump Gp - Steering 105-3635 47 B-7
Valve Gp - Shuttle Steering 112-1817 48 B-4
Valve Gp - Check Steering 111-7775 49 B-4
Pump Gp - Main Implement 191-0134 50 B-7
Filter Gp - Hydraulic Oil 174-6173 51 B-6
Pump Gp - Hydraulic Fan 174-2931 52 A-5
Hydraulic Oil Tank 171-5446 53 A-6
Valve Gp - Breaker Relief 9T-0818 54 A-6
Pump Gp - Secondary Steering 150-7585 55 A-5
Valve Gp - Steering Pressure Reducing 114-1267 56 B-3
Screen Gp - Filter 187-1667 57 A-6
Valve Gp - Secondary Steering Diverter 144-5330 58 A-4
Switch As - Steering Pressure 3E-6450 59 A-4
* The one stem valve is an attachment eld conversion. The two stem valve is standard.
The three stem valve is the logger attachment.
# Available in standard, logger, or high lift congurations.
@ Ride Control Attachment
TAP LOCATION
Tap
Number
Description
Schematic
Location
AA Tilt Head End E-5
BB Tilt Rod End E-5
CC Lift Head End E-4
DD Lift Rod End D-4
EE Brake Pressure D-2
FF Implement Relief D-7
GG Implement Return D-4
HH Pilot Pressure D-6
JJ Steering Pressure C-7
KK Oil Cooler Return B-6
LL Implement Pressure A-7
MM Steering Relief A-4
NN Hydraulic Fan Relief A-6
OO Rear Service Brake Pressure E-2
PP Front Service Brake Pressure E-2
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
Components are shown installed on a fully operable machine with the key and engine off, transmission shifter
in neutral and with parking brake set.
Refer to the appropriate Service Manual for Troubleshooting, Specifications and Systems Operations.
SCHEMATIC PART NUMBER: 171-3038, CHANGE: 00, VERSION: -
MEDIA NUMBER: RENR6019-01
THIS SCHEMATIC IS FOR THE 980G SERIES II WHEEL LOADER HYDRAULIC SYSTEM
A
B
C
D
E
1234567
A
B
C
D
E
1234567
LINE PATTERNS
Drain / Return Lines
Component Group
Pilot / Load Sensing Pressure
Pressure Line
CALLOUTS
Taps (Pressure, Sampling, Sensor - by letter)
YY
(52) VALVE GP - CONTROL
138-1234
Callout Number
(Machine Location from
Component LocationsTable)
Component
Name
Part Number
(10) BRAKE GP
SERVICE (FRONT)
208-5972
(11) BRAKE GP
SERVICE (REAR)
208-5972
(9) ACCUMULATOR AS
RIDE CONTROL
138-1292
(8) VALVE GP
SOLENOID
RIDE CONTROL
3E-8574
(6) CYLINDER GP
LIFT
111-8181
(5) CYLINDER GP
TILT
124-6228
(55) PUMP GP
SECONDARY
STEERING
150-7585
(52) PUMP GP
HYDRAULIC FAN
174-2931
(34) PUMP GP
PILOT / BRAKE
113-7750
(46) PUMP GP
TRANSMISSION
136-0529
(47) PUMP GP
STEERING
105-3635
(50) PUMP GP
IMPLEMENT MAIN
191-0134
(31) VALVE GP
MANUAL LOWER
DEAD BATTERY
112-1817
(17) VALVE GP
MAIN RELIEF
114-2789
(28) FILTER SCREEN
PILOT VALVE
6E-5065
(3) VALVE GP
LINE RELIEF
AUX HEAD END
4T-4162
AUXILLARY
CYLINDER
(2) VALVE GP
LINE RELIEF
AUX ROD END
4T-4934
(1) VALVE GP
MAIN CONTROL
114-2788
(12) VALVE GP
CONTROL
SERVICE BRAKE
191-1265
(13) PEDAL AS
RIGHT
193-1448
(16) BRAKE GP
PARKING
4E-8525
(24) BRAKE GP
PARKING
ACTUATOR
154-8042
(25) SWITCH AS
SERVICE BRAKE
LOW OIL PRESSURE
175-3244
(27) SWITCH AS
PARKING BRAKE
PRESSURE
174-4312
PARKING BRAKE
PRESSURE SPOOL
VALVE GP
PRESSURE RELIEF
SERVICE BRAKE
(23) VALVE GP
ACCUMULATOR
CHARGING
SERVICE BRAKES
172-6144
(22) ACCUMULATOR GP
FRONT
SERVICE BRAKES
111-9040
(21) ACCUMULATOR GP
REAR SERVICE BRAKES
111-9040
EE
OO
PP
CC
DD
GG
HH
FF
JJ
LL
NN
KK
AA
BB
MM
(36) VALVE GP
CONTROL
ELECTROHYDRAULIC
191-8735
(37) VALVE GP
STEERING
PILOT
173-0439
(38) SCREEN GP
STEERING
FILTER
154-1883
(33) CYLINDER GP
STEERING
115-1371
(42) VALVE GP
STEERING
166-8495
(43) VALVE GP
RELIEF
STEERING
CROSSOVER
9T-7418
(41) VALVE GP
SHUTTLE
STEERING
8J-6875
(56) VALVE GP
STEERING
PRESSURE
REDUCING
114-1267
(40) VALVE GP
RELIEF STEERING CROSSOVER
9T-7419
(39) VALVE GP
STEERING
NEUTRALIZER
8J-1553
(49) VALVE GP
CHECK
STEERING
111-7775
(48) VALVE GP
SHUTTLE
STEERING
112-1817
(29) VALVE GP
DIVERTER
RIDE CONTROL
115-9328
(15) VALVE GP
RELIEF
RIDE CONTROL
159-8201
(7) VALVE GP
SHUTTLE
RIDE CONTROL
141-1481
(59) SWITCH AS
STEERING
PRESSURE
3E-6450
(58) VALVE GP
DIVERTER
SECONDARY
STEERING
144- 5330
(57) SCREEN GP
FILTER
187-1667
(53) HYDRAULIC
OIL TANK
171-5446
(54) VALVE GP
BREAKER
RELIEF
9T-0818
(35) MOTOR GP
HYDRAULIC FAN
161-8919
(45) COOLER AS
HYDRAULIC OIL
130-7955
(44) VALVE GP
HYDRAULIC OIL
COOLER BYPASS
130-5202
(51) FILTER GP
HYDRAULIC OIL
174-6173
(14) VALVE GP
CHECK
RIDE CONTROL
104-7108
(20) VALVE GP
CHECK
RIDE CONTROL
9T-3096
(19) VALVE GP
LINE RELIEF
TILT BACK
9T-0818
(18) VALVE GP
LINE RELIEF
DUMP
4T-4933
(32) VALVE GP
PILOT
OIL MANIFOLD
142-3998
MACHINE COMPONENT LOCATIONS
PP
PP
OO
OO
NN
NN
LL
LL
KK
KK
JJ
JJ
JJ
HH
HH
GG
GG
FF
FF
EE
EE
EE
DD
DD
CC
CC
BB
BB
AA
AA
59
58
57
56
55
54
53
53
52
52
51
51
51
50
49
48
47
47
47
46
46
46
45
45
44
44
43
42
41
40
39
39
38
37
37
36
36
36
35
35
35
35
34
34
34
33
33
33
32
32
31
31
29
28
28
28
27
25
24
24
24
24
23
22
22
21
20
20
19
19
18
18
18
17
17
17
16
16
15
14
13
13
12
12
11
11
11
10
10
10
9
9
8
8
7
7
6
6
6
5
5
5
3
3
2
2
1
1
VIEW ALL CALLOUTS
