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INTERACTIVE SCHEMATIC
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KEYS
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Pressure
Switch
Temperature
Switch
Level
Switch
Flow
Switch
Circuit Breaker
T
ELECTRICAL SYMBOLS
Spring
(Adjustable)
Variability
Fluid
Conditioner
Pump
or Motor
BASIC HYDRAULIC
COMPONENT SYMBOLS
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SCHEMATIC SYMBOLS AND DEFINITIONS
HYDRAULIC SYMBOLS - ELECTRICAL
Transducer
(Fluid)
Transducer
(Gas / Air)
G
Generator
Electrical
Wire
Pressure
Switch
M
Electric
Motor
Pressure Switch
(Adjustable)
Temperature
Switch
Pressure
Switch
Temperature
Switch
Level
Switch
Flow
Switch
Circuit Breaker
T
ELECTRICAL SYMBOLS
Spring
Control
Valves
Restriction
Line Restriction
(Fixed)
2-Section
Pump
MAIN
AUX.
Spring
(Adjustable)
Variability
Line Restriction
(Variable)
Pressure
Compensation
Pump: Variable and
Pressure Compensated
Hydraulic Pneumatic
Energy Triangles
Fluid
Conditioner
Attachment
Pump
or Motor
BASIC HYDRAULIC
COMPONENT SYMBOLS
Line Restriction
Variable and Pressure
Compensated
Vented Pressurized Return Above Fluid Level Return Below Fluid Level
FLUID STORAGE RESERVOIRS
Pressure
Temperature
Flow
MEASUREMENT
Unidirectional
Bidirectional
ROTATING SHAFTS
One Position
Two Position
Three Position
Two-way
Three-Way
Four-Way
ENVELOPES
PORTS
CONTROL
Basic
Symbol
Spring
Loaded
Normal Position
A B
P T
A B
P T
Shifted Position
Infinite Position
Shuttle
Pilot
Controlled
VALVES
CHECK
Solenoid
or Manual
Solenoid
and Pilot
Solenoid and
Pilot or Manual
Solenoid
Servo
Thermal
Detent
COMBINATION CONTROLS
T
Fuse: A component in an electrical circuit that will open the circuit if too much current flows through it.
Switch (Normally Open): A switch that will close at a specified point (temp, press, etc.). The circle indicates
that the component has screw terminals and a wire can be disconnected from it.
Switch (Normally Closed): A switch that will open at a specified point (temp, press, etc.).
No circle indicates that the wire cannot be disconnected from the component.
Ground (Wired): This indicates that the component is connected to a grounded wire.
The grounded wire is fastened to the machine.
Ground (Case): This indicates that the component does not have a wire connected to ground.
It is grounded by being fastened to the machine.
Reed Switch: A switch whose contacts are controlled by a magnet. A magnet closes the contacts of
a normally open reed switch; it opens the contacts of a normally closed reed switch.
Sender:
A component that is used with a temperature or pressure gauge.
The sender measures the temperature or pressure.
Its resistance changes to give an indication to the gauge of the temperature or pressure.
Relay (Magnetic Switch):
A relay is an electrical component that is activated by electricity.
It has a coil that makes an electromagnet when current flows through it.
The electromagnet can open or close the switch part of the relay.
Solenoid:
A solenoid is an electrical component that is activated by electricity.
It has a coil that makes an electromagnet when current flows through it.
The electromagnet can open or close a valve or move a piece of metal that can do work.
Magnetic Latch Solenoid:
An electrical component that is activated by electricity and held latched by a
permanent magnet. It has two coils (latch and unlatch) that make electromagnet
when current flows through them. It also has an internal switch that places
the latch coil circuit open at the time the coil latches.
BASIC ELECTRICAL COMPONENT SYMBOLS
Push-pull Lever PedalGeneral Manual Push Button SpringManual Shutoff
MANUAL CONTROL
External Return
Internal Return
Simplified
Complete
Internal
Supply Pressure
RELEASED PRESSURE
REMOTE SUPPLY PRESSURE
PILOT CONTROL
Spring Loaded
Gas Charged
ACCUMULATORS
Crossing
Joining
LINES
Double Acting
Single Acting
CYLINDERS
Unidirectional
Bidirectional
FIXED DISPLACEMENT
VARIABLE DISPLACEMENT
NON- COMPENSATED
PUMPS
Unidirectional
Bidirectional
Unidirectional
Bidirectional
FIXED DISPLACEMENT
VARIABLE DISPLACEMENT
NON- COMPENSATED
MOTORS
Unidirectional
Bidirectional
Two
Position
Infinite
Positioning
FLOW IN ONE
DIRECTION
FLOW ALLOWED IN
EITHER DIRECTION
Three
Position
CROSS
FLOW
PARALLEL
FLOW
INTERNAL PASSAGEWAYS
1
2
AG-C4
111-7898
L-C12
3E-5179
9X-1123
Component
Part Number
Pin or Socket Number
Part Number: for
Connector Plug
Harness Identification Letter(s): (A, B, C, AA, AB, AC, ...)
Plug
325-AG135 PK-14
Wire Color
Wire Gauge
Receptacle
1
1
2
2
Sure-Seal connector: Typical representation
of a Sure-Seal connector. The plug and receptacle
contain both pins and sockets.
Deutsch connector: Typical representation
of a Deutsch connector. The plug contains all
sockets and the recept
acle contains all pins.
Fuse (5 Amps)
5A
Harness identification code:
This example indicates wire group 325,
wire 135 in harness "AG".
L-C12
3E-5179
Wire, Cable, or Harness Assembly Identification:
Includes Harness Identification Letters and Harness
Connector Serialization Codes (see sample).
Harness Connector Serialization Code: The "C" stands for
"Connector" and the number indicates which connector in the
harness (C1, C2, C3, ...)
HARNESS AND WIRE SYMBOLS
UENR3239-01
November 2012
432F Backhoe Loader
Hydraulic System
SEJ1-UP
LNR1-UP
Printed in U.S.A.© 2012 Caterpillar, All Rights Reserved
COMPONENT TABLE
= Graphic not avalible at time of publication.
Description
Part
Number
Machine
Location
Schematic
Location
IMPLEMENT PUMP GP 307-3069 1
B-4
HYDRAULIC TANK 358-9301 2 A-5
TANK GROUP 351-5888 3 A-5
HYDRAULIC COOLER 337-9751 4 B-4
HYDRAULIC FILTER 359-7232 5 B-3
HMU 341-7654 6 C-6
STEER CYL-FRONT 217-5097 7 B-6
LH: 358-5034
RH: 358-5035
TILT CYL (ST) N/A NOT SHOWN NOT SHOWN
TILT CYL (PL/IT) 358-5045 10
B-8
MP BUCKET CYL (OPT) 185-1839 11 A-8
F-6
F-3
432F (14FT): 320-6520
432F (16FT), 444F: 320-6522
432F (14FT): 320-6521
432F (16FT), 444F: 320-6523
LH: 381-8055
RH: 381-8054
BUCKET CYL 320-5937 16
F-4
E-STICK CYL (OPT) 320-5935 17 F-3
ACCUMULATOR (PILOT) 226-0420 18 C-5
RIDE CNTRL VALVE (OPT) 245-8780 19 C-8
RIDE CNTRL ACC (OPT) 382-8033 20 C-8
RIDE CNTRL SENSOR (OPT) 344-7391 21 C-8
TEMP SENSOR (OPT) 264-4297 22 C-4
DIFF PRES SWITCH (OPT) 134-0404 23 C-4
COUPLER VALVE (LDR) 359-7228 24 A-8
COUPLER CYL (LDR) 178-3713 25 A-8
LOADER VALVE (PL/IT) 359-7211 27 C-7
BACKHOE VALVE 359-7216 28 F-7
PATTERN CHANGING VALVE 300-4491 29 D-6
SWING CUSHION VALVE 320-7812 30 F-5
F-3
F-6
F-2
F-8
VALVE GP-PILOT (LDR) 382-4996 33 D-7
STD: 359-7246
W/SWITCH: 359-7247
DTNT and SWITCH: 359-7248
PILOT MANIFOLD (BASIC +4) 359-7224 35
D-4
PUMP DISCHARGE PRES SNSR 344-7391 36 C-5
BOOSTED BRAKE VALVE 220-8226 37 D-3
432F:
N/A
444F: 340-7028
HOSE BURST CHECK VALVE (BOOM) 347-1128 40
F-6
HOSE BURST CHECK VALVE (STICK) 347-1129 41 F-4
HOSE BURST CHECK VALVE (LIFT) 262-7081 42 B-8
HOSE BURST CHECK VALVE (TILT) 262-7079 43 B-8
POWERED SIDESHIFT VALVE 351-1637 44 B-2
POWERED SIDESHIFT CYL 347-2223 45 F-1
8TH AUXILIARY VALVE 319-2155 46 E-1
8TH AUXILIARY PILOT VALVE 373-7028 47 D-1
9TH AUXILIARY VALVE 319-2158 48 D-2
9TH AUXILIARY PILOT VALVE 373-7029 49 C-1
COUPLER VALVE (HOE) 358-2091 50 A-3
COUPLER CYLINDER (HOE) 361-1139 51 B-3
COMPONENT LOCATIONS
8LIFT CYL
13
F-6BOOM CYL
F-4
15 F-5SWING CYL
34
E-8VALVE GP-PILOT (STAB)
31
308-3437STAB CHECK VALVE
STICK CYL 14
39ALL WHEEL STEER VALVE A-6
B-8
32359-7227VALVE GP-PILOT (HOE)
12
320-5938STABILIZER CYL
(NOT SHOWN)
TAP TABLE
Tap Number Description
Schematic
Location
T1
PUMP DISCHARGE PRESSURE C-5
T2 RIGHT REAR SERVICE BRAKE (See Volume 3) C-4
T3 REAR PARK BRAKES (See Volume 3) D-5
TAP LOCATIONS
Pressure, Sampling, Sensor
UENR3239-00
30 Page, (Dimensions: 39 inches x 28 inches)
LINE PATTERNS
Drain / Return Lines
Component Group
Pilot / Load Sensing Pressure
Pressure Line
Attachment
Air Line
CALLOUTS
Taps (Pressure, Sampling,Sensor) by letter
Components by number
YY
52
432F and 444F BACKHOE LOADER HYDRAULIC SCHEMATIC
MEDIA NUMBER: UENR3239-00
PART NUMBER: 362-9207, CHANGE: 01, VERSION: --
Components are shown installed on a fully operable machine.
Refer to the appropriate Service Manual for Troubleshooting, Specifications.
DRAIN / RETURN LINE
HYDRAULIC CIRCUIT COLOR DESCRIPTIONS
IMPLEMENT AND STEERING PUMP CIRCUIT
SWING CYLINDER CIRCUIT
STEERING CYLINDER CIRCUIT
PILOT OIL CIRCUIT
BUCKET CYLINDER CIRCUIT
STICK CYLINDER CIRCUIT
LOAD SENSE CIRCUIT
SUPPLY LINE
BACKHOE VALVE AUX CIRCUIT
E-STICK CYLINDER CIRCUIT
BOOM CYLINDER CIRCUIT
STABILIZER CYLINDER CIRCUIT
BOOSTED BRAKE OIL CIRCUIT
LIFT CYLINDER CIRCUIT
TILT CYLINDER CIRCUIT
LOADER VALVE CIRCUIT
POWER SIDE-SHIFT CYLINDER CIRCUIT
SIDE-SHIFT LOCK CYLINDER CIRCUIT
COUPLER CIRCUIT (HOE)
12345678
A
B
C
D
E
F
12345678
A
B
C
D
E
F
D
DLS
LIFT
TILT
AUX
FRONT STEER CYL.
ACC
R
T
PS
H
RH STAB
BOOM
SWING
BUCKET
STICK
LH STAB
E-STICK
A4
B4
B3
A6
B6
A1
B1
LB
LA
TA
TB
LAB
LAA
RS2
RS1
BA
BB
R4
R2
SB
SA
LS1
LS2
EA
EB
J1
J2 T2 T3 J3
T1
P ACC DIAG
OPERATOR LEFT JOYSTICK
OPERATOR
LEFT
OPERATOR
RIGHT
STABILIZER JOYSTICK
TILT
LIFT
LOADER JOYSTICK
P
LAA
EB
LAB
EA
TBTALALB
LS2
LS1
RS2
RS1
L1L3L2L4
R2R4R3R1
SBBABB SA
L4R1 R3 L2
A1
B1
A2
B2
A3
B3
A3
BRK
LEFT
BRAKE
PEDAL
TO REAR AXLE
LEFT WHEEL
BRAKE
TO REAR AXLE
RIGHT WHEEL
BRAKE
S
U
LIFT
TILT
AUX
A2
B2
A5
B5
A7
B7
Pil
BL
C2
V2
Pil
BL
C2
V2
SIDESHIFT
LOCK
F1
F2
R2
R1
REAR STEER CYLINDER
FRONT STEER CYL.
AWS VALVE 444F ONLY
HMU-R
HMU-L
R
L
B
A
NOTE B
NOTE B
P8
LS8
T8
T7
P7
T6
P6
B
A
L1
L3
OPERATOR RIGHT JOYSTICK
RIGHT
BRAKE
PEDAL
351-5888
358-9301
337-9751
307-3069
214-5079
(39) VALVE GP - AWS (444F ONLY)
340-7028
359-7232
134-0404
264-4297
220-8226
359-7224
226-0420
344-7391
341-7654
300-4491
382-4996
359-7211
344-7391
(20) ACCUMULATOR - OPTIONAL
382-8033
245-8780
344-7391
358-5045
370-7083
432F:
444F:
185-1839
178-3713
359-7228
359-7227
320-5935
320-5938
308-3437
320-6521
320-6523
432F(14ft):
432f (16ft), 444F:
381-8054
LH:
RH:
381-8055
320-5937
347-1129
320-7812
320-5938
320-6520
320-6522
432F(14ft):
432f (16ft), 444F:
308-3437
347-1128
359-7216
262-7079
262-7081
359-7227
359-7247
359-7248
W / SWITCH:
DTNT and SWITCH:
9TH AUX
A2B2
PSS
A1B1
8TH AUX
A2B2
T2
LS2
P2
LST M P
8TH AUXILIARY & POWERED SIDESHIFT
P8
LS8
T8
T6
P6
C2C1
P
T
T6
P6
T8
P8
LSC1 C2
P
T
POWERED SIDESHIFT
LS8
BACKHOE COUPLER
T7
P7
9TH AUXILIARY
373-7028
373-7028
319-2155
(45) CYLINDER - POWER SIDE SHIFT
347-2223
373-7029
(45) CYLINDER -
POWER SIDE SHIFT
347-2223
(44) VALVE -
POWER SIDE SHIFT
351-1637
358-2091
347-2223
ADDED AS AN ADDITONAL SLICE TO
8TH and POWERED SIDESHIFT VALVE
T2
T1
T3
(3) TANK GROUP - FILTER / BREATHER / SIGHT GAGE
(2) TANK - HYDRAULIC
(4) COOLER - HYDRAULIC
(1) PUMP GP - IMPLEMENT
(7) CYLINDER - FRONT STEER
(5) FILTER - HYDRAULIC
(23) SWITCH - DIFF PRESS
(OPTIONAL)
(22) SENSOR - TEMP
(OPTIONAL)
(37) VALVE - BOOSTED BRAKE
(35) MANIFOLD - PILOT (BASIC +4)
(18) ACCUMULATOR - PILOT
(36) SENSOR -
PUMP DISCHARGE
(6) VALVE HMU - LOAD SENSE RELIEF
(29) VALVE - PATTERN CHANGE
(33) VALVE GP - PILOT
(27) VALVE - LOADER (PL/IT)
(21) SENSOR -
RIDE CONTROL (OPT)
(19) VALVE - RIDE CONTROL (OPT)
(8) CYLINDER - LIFT
(10) CYLINDER - TILT
(11) CYLINDER -
MP BUCKET (OPT)
(25) CYLINDER - COUPLER
(24) VALVE - COUPLER (LDR)
(32) VALVE GP - PILOT (HOE)
(17) CYLINDER - E STICK
(OPT)
(12) CYLINDER - STAB
(31) VALVE - CHECK (STAB)
(14) CYLINDER - STICK
(15) CYLINDER - SWING
(16) CYLINDER - BUCKET
(41) VALVE - STICK
HOSE BURST
(30) VALVE - CUSHION
(12) CYLINDER - STAB
(13) CYLINDER - BOOM
(31) VALVE -
CHECK (STAB)
(40) VALVE - BOOM
HOSE BURST
(28) VALVE - BACKHOE
(43) VALVE - TILT
HOSE BURST
(42) VALVE - LIFT
HOSE BURST
(32) VALVE GP - PILOT (HOE)
(34) VALVE GP - PILOT (STAB)
(47) VALVE - PILOT
8TH AUX
(48) VALVE - 9TH AUX
(46) VALVE - 8TH AUX
(49) VALVE - PILOT
9TH AUX
(50) VALVE - COUPLER
(HOE)
(51) CYLINDER -
COUPLER (HOE)
RIGHT SIDE
T1
49
48
47
46
44
36
34
3332
31
31
28
27
12
12
10
10
8
86
4321
VIEW ALL CALLOUTS
LEFT SIDE
43
43
42
42
37
20
20
2019
11
11
5
VIEW ALL CALLOUTS
BOTTOM
T3 T2
51
503530
29 25
24
18
VIEW ALL CALLOUTS
STICK
41
40
16
15
14
13
VIEW ALL CALLOUTS
