Component Locations
Description
CONNECTOR - ORIFICE
8C-0564
1
F-10
128-7063 (HM U S T EE R N I G) 1 13 -9 2 34
2 3
F-10
240-7313
4
CORE AS - HYDRAULIC OIL COOLER CYLINDERGP N DERGP-AUX(FURNISHEDBY SUPPLIER)
NOTEE
C YL N I DE R GP - H YD RA UL C I ( ST EE RI NG ) R ( H, L H)
1 15 -1 37 1
C YL N I DE R GP - L F I T
CYLINDER GP -TILT R ( H)
5 6
F -2 ,H 1 -
7
H7 -
8
H -9
112-5003 (HIGHLIFT MACHINES) (NOTE D) 124-0616 (LOGGINGMACHINES)(NOTE C) 124-6228
9
H-9
259- 1407
M OT O R GP - P S I T ON ( H YD R AU LC I F A N) ( NO N- R EV E RS I NG )
10 11
C -9
292-9964
12
C-12
235-6501
13
D-12
P UMP GP -G -G EA R( R(S EC ONDA RY ST EER N I G)
150- 7585
14
B 7-
(HMUSTEERING)(NOTEH)
2 71 1 - 82 4
15
PUMP GP - PISTON (HYDRAULIC FAN)
235-2716
16
B-9
PUMP GP - PISTON S ( TEERING)
105-3635
17
C-12
(COMMANDCONTROLSTEERING) 154-2883
18
E-3
200-5978
19
E-12, F-12
STRAINER TANK GP - HYDRAULIC
234-8928 240-8704
20
C-11
2 20 0 - 81 4
21
C1 - 1
VALVE GP -C -CHECK C ( OOLER BYPASS)
206-8809
22
D-10
(COMMANDCONTROLSTEERING) 111-7775
23
E-4
VALVE GP - DEMAND FAN
191-8735
24
B-9
V AL VE G P - DI VE RT ER (S (S EC ON DA RY S TE ER N I G)
1 44 5 - 33 0
25
C 6-
26
H1 - 2
VALVE GP -CHECK (STEERINGQUAD)
V AL VE G P- MA MA N I CO CO NT RO L( L( 2- FU NC TI ON ) S ( TD ) VALVE GP -MAINCONTROL (3-FUNCTION)
2 90 6- 00 5
27
H- 12
V ALVEG P- M AN UA L( LOW ERI NG CON TROL)
112- 1817
28
E-1 2
VALVE GP -PILOT (OILMANIFOLD,2-FUNCTION)(TILT,LIFT)
206-5186
29
F- 8
VALVE GP -PILOT (OILMANIFOLD, 3-FUNCTION)(TILT, LIFT, ANDAUX)
290-8981
30
F- 8
(COMMANDCONTROLSTEERING) 173-0439
31
E-4
VALVE GP -PILOT (STEERING)
(LOGGERATTACHMENT) 290-6 007
23
31
7
37
401
PUMPor MOTOR
8
SPRING (ADJUSTABLE)
VARIABILITY
4
CONTROLVALVES
SPRING
FLUIDCONDITIONER
4 T- 49 34
32
G1 - 1
4 T- 41 62
33
G1 - 1
VALVE GP -RELIEF (LINE, TILT CYLHEADENDPORT)
(NOTE A) (NOTE B)
4T-4932 4T-4935
34
G-9
VALVE GP -RELIEF (LINE, TILT CYLRODENDPORT)
(NOTE A) 4T-4933 (NOTE B) 4T-6103
35
G-10
114-2789
36
F-12
8J-6875
37
D-4
VALVE GP - RELIEF (MAIN) VALVE GP -SHUTTLE (PRIMARY&SECONDARYSTEERPILOTOIL) VALVE GP - STEERING
(COMMANDCONTROL STEERING) 166-8495 (HMUSTEERING) 2 55 2 - 85 6
38 39
E-1 G-2
VALVE GP STEERINGNEUTRALIZER
(COMMANDCONTROL STEERING) 8 J- 15 53 (HMUSTEERING) 1 46 7 - 57 1
40 41
D3 - ,E 3 G-5
203 301
TWO POSITION
AB
ACCUMULATORGP -BRAKE (CHARGED)
THREEPOSITION
(NOTE E)
111-9040 220- 2720 249-5550
101
B 2-
206-0408
102
C-1
193-1448
103
S EN SO R GP - P OS T I O I N (R OT AR Y) ( BR AK EP ED AL )
2 14 -4 86 3
1 04
C -3
105-6117
105
C-3
174-4312 175- 3244
106 107
B-1 B 2-
1 72 6 - 14 4
1 08
B3 -
106- 1774
109
B 1-
201-3200 260-9632
110
C-2
(NOTE F) (NOTE E)
SWITCH AS - LIMIT (STOP LIGHT) SWITCH AS - PRESSURE
(NOTE E)
V AL VEG P- A CC CC UMU LA TO RC RC HA RG N I G( G( BR AK E) V ALVE GP - BR BRA KE CONT ROL (P (PA RK N I G) (NOTE F) (NOTE G, H)
TWO-WAY
FOUR-WAY
THREE-WAY
CHECK VALVES
PT SHIF TEDPOSIT ION
I N FN I I T E P O STI I O N
BASIC SYMBOL
SHUTTLE
SPRING LOADED
MEASUREMENT
28
PILO T CONTROLLED
ROTATING SHAFTS
9 16
24
38
6
18
PRESSURE
FLOW
TEMPERATURE
UNIDIRECTIONAL
BIDIRECTIO N AL
FLUIDSTORAGE RESERVOIRS
20
21
108 2 0 1 2 0 4
402 404
7
403
1
2
406407
29 35
10 1 0 1 1 0 6 1 0 9
13
DD
EE
17
108 109
40
103 104 1 0 5 1 1 0
16
19
26
27
30
32
33
34
36
4 02 4 05
BB
980H Wheel Loader Hydraulic System
V ENT E D
CC
RETURNABOVEFLUIDLEVEL
P R E S S U RI E Z D
RETURNBELOWFLUIDLEVEL
COMBINATIONCONTROLS
MHG1-UP A8J1-UP JMS1-UP
FF 23
SOLENOID
SOLENOID or MANUAL
SOLENOIDand PILOTor MANUAL
SOLENOID and PILOT
SERVO
THERMAL
DETENT
MANUAL CONTROL SYMBOLS
2 8 4 01 PUSH-PULL LEVER
12
MANUALSHUTOFF
G ENERAL MANUAL
P USH BUTTON
PEDAL
SPRING
PILOT CONTROL SYMBOLS
8 4
11
RELEASEDPRESSURE
9
REMOTESUPPLYPRESSUR E
22
203 301
INTERNALRETURN
SPRING LOADED
SIMPLIFIED
CROSSINGANDJOININGLINES
GASCHARGED
LINESCROSSIN G
HYDRAULICPUMPS
302
INTERNAL SUPPLYPRESSURE
COMPLETE
HYDRAULICANDPNEUMATICCYLINDERS
SINGLEACTING
LINESJOINING
DOUBLEACTING
INTERNALPASSAGEWAYS
HYDRAULICMOTORS
24 FIXED DISPLACEMENT
404
6 7 201 204
14
20
25
38
31
21 10
18
VARIABLEDISPLACEMENT NON-COMPENSATED
FIXED DISPLACEMENT
VARIABLEDISPLACEMENT NON-COMPENSATED
1
2
19
26
27
UNIDIRECTIONAL
UNIDIRECTIONAL
29
30
32
33
34
BIDIRECTIONAL
BIDIRECTIONAL
35
36
40 2 4 05
101106 109
THREE POSITION
INFINITE POSITIONING
FLOWINONE DIRECTION
© 2006 Caterpillar AllRights Reserved
3 7 4 03 4 06 4 07
TWO POSITION
CROSS FLOW
PARALLEL FLOW
FLOWALLOW EDIN EITHERDIRECTIO N
Printed in U.S.A.
MACHINE COMPONENT LOCATIONS
Part Machine Schematic Number Location Location
CONTROL GP - FOOT BRAKE
ACTUATORAS
ATTACHM ENT
AB
PT NORMALPOSITION
302
PUMP: VARIABLEand 2-SECTIONPUMP PRESSURECOMPENSAT ED
LINERESTRICTION VARIABLEand PRESSURE COMPENSATED
VALVE PORTS
CONTROL VALVES
11
BrakeCon trol System
LINERESTRICTION (FIXED)
HYDR A U LCI PNEU M A TCI ENERGYTRIAN GLES
VALVES
VALVE ENVELOPES
22
RESTRICTION
PRESSURE COMPENSATION
LINERESTRICTION (VARIABLE)
ACCUMULATORS
V AL VE GP - RE LI EF L ( N I E, AU X CY L HE AD E ND P OR T)
VALVE GP -BRAKE CONTROL (SERVICE)
40
EXTERNALRETURN
V AL VE G P- R EL E I F( LI NE ,A UX C YL R OD E ND P OR T)
Description
14
12
G-5
V AL VE - BR BR EA KE RR RR EL E I F( HY DR AU LI C TA NK )
(NOTE E)
BASICCOMPONENTSYMBOLS MAINAUX.
13
C 1- 0
2 55 - 68 05
PUMP GP - GEAR I(MPLEMENT )
SCREENGP -CASE DRAIN (STEERINGPILOT)
FLUID POWER SYMBOLS
RENR8679-01 May 2006
103 1 0 4 1 0 5 1 10
ONEPOSITION
PUMP GP - GEAR P ( ILOT, BRAKE) PUMP GP -METERING
25
FF 17
D-10
1 11 -8 18 1
FILTERGP -OIL (HYDRAULIC)(FAN/ IMP PILOT / BRAKE RETURN)
EE
H-10,H-11
124-5004 ( HI G H LI F TM AC H N I E S) ( N OT E D ) 1 24 -6 2 27 (LOGGINGMACHINES)(NOTEC) 112-0617
CYLINDER GP - TILT (LH)
DD
Part Machine Schematic Number Location Location
CONNECTOR
Electrical Symbols Table
RADIATORGP- FAN
C-2
HydraulicSymbols (Electrical)
301
M
G
203
A
16
IMPLEMENT VALVE
LINESGPOILCOOLER
B
Transducer (Fluid)
Transducer (Gas / Air)
Generator
Electric Motor
AxleOil Coo ler Attachment Description
COOLER AS - AXLE OIL A ( XLE)
Part Machine Schematic Number Location Location 200-4169
201
FILTER - MAGNETIC
251-6351
202
PUMP GP -GEAR (AXLE OIL COOLER)
249-0046
203
V AL VE G P- C HE CK (A XL E OI L CO OL ER B YP AS S)
1 30 -5 20 2
2 04
A-11 A-11
LOADER FRAME
A-12
Part Number
ElectricalSymbols (Electrical)
A B
RIGHT SIDE VIEW T
Pressure Symbol
Machine Schematic Location Location
M OT OR GP GP - RE RE VE RS N I G( G( BI D - R I EC TI ON AL )
2 40 7 - 73 2
3 01
C8 -
VALVE GP - REVERSING
213-1040
302
C-7
(NOTE E, H)
Part Number
Electrical Schematic Example
401
Wire Circuit Number Identification
302
FRAMEGP-ENGINEEND
9T3 - 09 6
4 02
G -7 , H -7
VALVE GP - CHECK (PILOT) VALVE GP - DIVERTER VALVE GP - RELIEF VALVE GP - SHUTTLE V AL VE G P- S OL EN OI D( D( AR TI FI CI AL S G I NA L)
207-1810 115-9328 NOTE E 141-1481 1 52 8 - 34 0
403 404 405 406 4 07
G-7 G-6 G-6 H-7 H7 -
W ri eC ol or
W ri eG au g e
Previous Standard
H-6
V A LV E G P -C HE C K (D E AD E N GI N E, L I FT A R ML OW E R)
325-PK Circuit Identification Number
201
Wire Color
325-AG135 PK-14
LEFT SIDE VIEW
C
Hydraulic Schematic Example Current Standard
Current Standard Harness identification code This example indicates wire 135 in harness "AG".
204
Machine Schematic Location Location
138-1292 221-1762
Flow Symbol
Level Symbol
Wire Number Identification Codes
D
RideControl Attachment Description
Temperature Symbol
F O R W A R D
The cooling system is a hydraulicall y driven fan, that is controlled by an on demand fan controlsy stem. The on demand fan controlsyst em controls the fan speed in order to provide the required amount of cooling air. This will maintain system temperature. During heavy machine operation or high ambient temperatures, the on demand fancontrol system will increase the fan to themaximum speed. During light usage and lower ambient temperature, the ondemand fan controlsyste m willmaintai n a lower fan speed. Thi s can result in lower horsepower requirements. The on demand fan controls the speed of the fan system through theuse of variable displacement piston pump. This will vary the volume of hydraulic oil to the hydraulic fan motor. The volume of oilthat is produced by the hydraulic fan pump is controlled by the pump controlvalve. T he reversing fan controlrevers es the rotation of thecooling fan in order to purge the radiator of debris buildup.
ACCUMULATORGP (CHARGED)
ElectricalWire
Temperature Switch
401
Reversing Fan Attachment Description
Pressure Switch (Adjustable)
Pressure Switch
LINESGP- AXLEOILCOOLER
A-10, A-11
Theaxleoilcoolerperformstwofunctions.Theenginecoolantcoolstheaxleoil thatflowsthroughthe axle oilcool er if the axleoil temperature is higher than the normaloperating temperature. The axle oilcoolstheenginecoolantthatflowsthroughtheaxleoil cooleriftheenginecoolanttemperatureis higher than the normaloperati ng temperature. The engine coolant flows through coolant hose assemblies to the axle oilcooler and flows back to the enginethrough coolant hose assemblies. The flowof the axle oil through the axle oilcooler helps keep the axle housings (front andrear) and internal brake components cool
16: Fan Pump 301: Reversing Fan Motor (Replaces Standard Fan Motor) 302: Reversing Valve
Wire Color
Wire
325-PK-14
C
B
D VIEWA-A
Circuit Number Identification
SECTIONB-B
A
Wire Gauge (EXAMPLE VALVE)
Note: This is an example of possible location.
The optionalr ide controlsy stem provides a means fordampening the forces of thework tool which produce a pitching motion as the machine travels over rough terrain.
AXLE OIL COOLER ATTACHMENT ATTACHMENT
AUTO REVERSING FAN ATTACHMENT ATTACHMENT
403
NOTE A: USEDWHENEQUIPPEDWITH COMPONENT #26 NOTE B: USEDWHENEQUIPPEDWITH COMPONENT #27 NOTEC:USEDON LOGGINGMACHINES NOTE D: USEDONHIGHLIFT MACHINES NOTE E: CHECK PARTS MANUALFORYOURMACHINE PART NUMBERS NOTE F: USEDONJMS NOTE G: USEDONMHG NOTE H: USEDONA8J
EE
13
Tap Locations Pressure, Sampling, and Sensor Tap Number AA
Description BRAKEACCUMULATORPRESSURE
17
Schematic Location B-2
BB
FRONTBRAKEPRESSURE
C-4
CC
R EA R BR AK E PR ES SU RE
C-4
DD
PRESSURESWITCH- SECONDARYSTEERING
B-6
EE
STEERINGLOADPRESSURE
C-12
FF
STEERINGPUMPPRESSURE
C-12
407 404
VIEWC-C
FF
SECTIOND-D
RIDE CONTROL ATTACHMENT
PILOT & STEERING PUMPS
1 0 9 7 e 6 g a P 8 0 3 R N E R
12
11
10
9
5
8
7
9
8
6
TILT
AUX
26
LIFT
4
2
1
METERING ORIFICE
6
SEE LOC E-6
6
PILOT PORT “B”
CYL PORT “B”
H
407
27
PILOT PORT “A”
406 41
402
STOP
STOP CROSSOVER RELIEF
34
33
32
3
JJ 401
H
5
PILOT CONTROL SPOOL
RIDE CONTROL ATTACHMENT
7
CYL PORT “A” E S O L C R E W O L
G
K C A B
35
E S I A R
NN
405
K C P A M R U D
E S R I E A W R O L
N E P O
SEE LOC C-5
403
PUMP PORT
3
SEE LOC D-6
404 1
36
DIRECTIONAL SPOOL
G
39
BACK-UP RELIEF
MM 15
MAKE-UP CHECKS
KK SEE LOC E-6 FLOW CONTROL ORIFICE
OO
HMU SUPPLY PORT
SEE LOC B-5
HAND METERING UNIT STEERING (HMU)
F TO BRAKE CONTROL SYSTEM
2
DUMP
GG
29
LOWER CLOSE
LOWER
F
30 18
JJ
SEE LOC B-3
6
SEE LOC E-6
6 38
FLOAT
19 28 RACK BACK
II
SEE LOC E-5
JJ
SEE LOC F-5 (CCS) H-6 (HMU)
OPEN RAISE
RAISE
KK
E
KK SEE LOC E-6
CROSSOVER RELIEF
II
23
SEE LOC E-6
SEE LOC E-5 (CCS) G-6 (HMU)
SHUTTLE VLV
31
E
HIGH PRESSURE H.E. OR R.E
G N I R E E T S
DIRECTIONAL SPOOL
E S N E S
STOP
LL T N E M E L P M I
1 0 - 2 9 r o 7 l o 6 C , 8 e g a R P 0 N 3 E R
E K A R B / T O L I P
19
IMPLEMENT RETURN
STEERING LOAD SENSE SIGNAL
IMP PI LOT RET URN
P ILOT ST EERI NG RETU RN
MM
MAKE UP CHECK
SEE LOC D-5
BACK UP RELIEF
SEE LOC D-5 (CCS) G-6 (HMU)
SEE LOC D-6
PRESSURE REDUCING VLV
STOP
D OIL FROM BRAKE CHARGING VALVE
HH G N I R E E T S
301 A
21
17
FAN MOTOR
SEE AXLE OIL COOLER ATCH LOC A-9
11
C
104 105
FRONT AXLE
TO TRANSMISSION CONTROL
FF
10
FAN MOTOR
N O I T C U S E K A R B / T O L I P
102
25
N R U T E R
PUMP COMPENSATOR
N O I T C U S
NN
SEE LOC D-1 (CCS) G-6 (HMU)
OO
SEE LOC D-1 (CCS) F-6 (HMU)
HH
BB
R E E T S
14 24
P M I
SEE LOC D-12
GG
AA DD
16
FAN SUCTION
FLOWTHROUGHPORT
101
ACCUMULATOR PORT
P
109
PRESSURE PORT
SEE LOC F-12
SEC STEER SUCTION
A2
204
T
TANK PORT
B
106
ACCUMULATOR PORT
SECONDARY STEERING PRESSURE SWITCH
SECONDARY STEERING
SEE FAN / BRAKE CIRCUIT
D
FRONT BRAKE PRESSURE A1
FAN PUMP
B
C
C
302
AUTO REVERSING FAN ATTACHMENT
R E E T S
C
REAR BRAKE PRESSURE
RELEASE APPLY
110
ND
CC
&
12
103
TO BRAKE LIGHTS
NC
STEERING LOAD PRESSURE
SEE LOC B-5
NN
P
C1
20
EE
SEE LOC C-5
COMMAND CONTROL STEERING (CCS)
T
B
OO
REDUCED PILOT PRESSURE
LL
C2
e n i g n E
40
37
SEE LOC D-6
r e l o o C
TO TRANS.
STEERING PUMP PRESSURE
D
MM
4
22
SEE LOC C-3
13
D A O L
AA
BRAKE ACCUMULATOR PRESSURE
NC
ND
TRANSMISSION CONTROL
C
NC
108 C
A X C L O E O L OE I R L
FRONT AXLE
204 203
TO RETURN FILTER
A
201
LINES GROUP COLOR DESCRIPTIONS STEERING PUMP OUTPUT
LINE PATTERNS
PILOT/BRAKE PUMP OUTPUT IMPLEMENT PUMP OUTPUT SECONDARY STEER PUMP OUTPUT
Pilot / Load Sensing Pressure
SUPPLY LINE DRAIN / RETURN LINE STEERING
107
REAR AXLE
Pressure Line
FAN PUMP OUTPUT
BRAKE CONTROL SYSTEM
Drain / Return Lines
CIRCUIT
ComponentGroup
STEERING CYLINDER CONTROL CIRCUIT
Attachment
TILT CYLINDER CONTROL CIRCUIT
PART#: 242-4309 CHG04 &HE00 (STEER&IMP HYDCIRCUIT) PART#: 142-0726 CHG02 &CHG00 (BRAKECONTROLCIRCUIT) PART#: 213-1040 CHG01 (VALVEGP- REVERSING)
LIFT CYLINDER CONTROL CIRCUIT
Air Line
IMPLEMENT CONTROL CIRCUIT AUX CYLINDERCONTROL CIRC UIT
CALLOUTS
BRAKE CONTROL CIRCUIT AUTO REVERSI NG FAN CONT ROL CIRCUIT
YY
Taps (Pressure,Sampling,Sensor)by
52
Components by
Components are shown installed on a fully operable machine with the key and engine off and transmission shifter in neutral.
letter
AXLE OIL COO LER PUMP OU TPUT AXLE OIL RET URN
12
11
10
9
8
7
6
5
A
THISSCHEMATICISFORTHE980HWHEELLOADER
MAIN PILOT CONTROL CIRCUIT
REAR AXLE
202
PARKINGBRAKE INDICATIONSW
TOSEMS
Refer to the appropriate Service Manualfor Troubleshooting, Specifi cations and Systems Operations
number
4
3
2
1
