RENR6484-03
30 Page, (Dimensions: 39 inches x 28 inches)
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
FLUID POWER SYMBOLS
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 ACTING
SINGLE 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
AB
PT
AB
PT
SHIFTED POSITION
INFINITE POSITION
CONTROL VALVES
ATTACHMENT
MANUAL SHUTOFF
SHUTTLE PILOT
CONTROLLED
Hydraulic Symbols (Electrical)
Electrical Symbols Table
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
T
Pressure
Symbol
Temperature
Symbol
Level
Symbol
Flow
Symbol
Electrical Symbols (Electrical)
©
2008 Caterpillar
All Rights Reserved
Printed in U.S.A.
RENR6484-03
December 2008
432E, 434E, 442E, and 444E
Hydraulic System
432E:
BXE1-2199
434E:
FSH1-899
442E:
GKZ1-599
444E:
LBE1-599
Backhoe Loader
COMPONENT LOCATIONS
2
1
56
5
4
4
6
2
1
7
7
8
8
8
9
9
9
10
10
10
11
11
11
13
12
12
13
15
15
14
14
14
16
16
19
192021
202127
27
28
28
31 30
Tap Description
T1 Pump Discharge
T2 Load Sense
SOS Oil Sampling
TAP LOCATIONS
(A) Outlet Manifold
(B) Auxiliary Control Valve
(C) Extendable Stick Control Valve
(D) Bucket Control Valve
(E) Swing Control Valve
(F) Left Stabilizer Control Valve
(G) Right Stabilizer Control Valve
N
A
BCDEF
GH I
BACKHOE VALVE
30 31
The 420E/430E machines are equipped with a pilot controlled backhoe valve that is
visible with the floor plate at the rear of the cab removed.
This illustration shows a eight bank backhoe valve in a 420E Backhoe Loader. The
components in the backhoe valve are:
SOS
Implement and
Steering Pump
HYDRAULIC OIL FILTER
SOS
Filter Bypass Switch
5
The 432E/434E/442E and 444E machines are all
equipped with the pilot controlled loader valve as
shown in this illustration.
The loader valve is accessed from below the floor
plate. The loader control valve group contains:
LOADER VALVE
E
27 28
D
C
B
A
Travel at high speeds over rough terrain causes bucket movement. The
optional Ride Control System acts as a shock absorber by absorbing
bucket forces, which stabilize the machine.
The Ride Control System components include; ride control relay (A), ride
control solenoids (B), ride control accumulator (C), and ride control
pressure switch (D).
Two solenoids are now used on the "E" Series machines Ride Control
System.
The Ride Control System, on machines with the optional autoshift
transmission, is controlled by the Machine ECM. The Machine ECM
monitors the position of the ride control switch and determines when to
operate the ride control system.
RIDE CONTROL
B
A
C
D
IMPLEMENT / STEERING PUMP
The implement and steering pump on the
432E, 434E, 442E and 444E machines is
similar to the "D" Series machines, but now
includes a torque control solenoid (not
visible). The torque control solenoid provides
an additional pump setting.
The implement and steering pump is located
below the floor plate in the cab. The pump
control valve (H) contains a torque control
spool adjustment screw (B) and a flow com-
pensator adjustment screw (A). The adjust-
ment screws and the load sensing pressure
tap (T2) are accessible from the cab.
Implement and
Steering Pump
1
F
View of mechanically controlled loader valve with floor plate removed.
Loader Valve
These illustrations show the implement and steering pump out of the machine. The following components are visible:
Torque control adjustment (A), Flow compensator adjustment (B), Load sensing pressure tap (T2), Inlet port (C),
Case drain port (D), Torque control solenoid (E), Discharge pressure tap (T1), Torque limiter (F), Outlet port (G)
B
C
D
THREE BANK VALVE (PILOT OPERATED)
G
H
J
K
L
M
P
R
N
E
G
A
B
E
F
D
C
D
E
C
A
B
T2
T2
T1
T2
T1
C
The 432E, 434E, 442E and 444E machines are equipped with hydraulically assisted master cylinders,
which decreases the amount of pedal effort when braking. This illustration shows the boosted brakes
valve group, which uses oil from the pilot accumulator to add boost to the master cylinder. The hydraulic
force multiplies the pedal effort so the operator can get more braking force with less effort.
The brake boost valves are connected to the master cylinder (A) at each brake pedal (B). Oil enters
the master cylinder through the supply hose (C) and exits the master cylinder through the return hose
(D). The oil flows to the service brakes through the hoses (E) at the bottom of the master cylinder.
The master cylinders can be removed from the machine from inside the operator's compartment.
This illustration shows a sectional view of the boosted brake valve group. When the brake pedal is
depressed, the boost brake valve moves to the left and inlet oil from the pilot manifold is directed
to the master cylinder.
BOOSTED BRAKES
J
L
M
K
Drain
EIGHT BANK VALVE (PILOT OPERATED)
For other bank valve configurations see RENR6487 (Specifications Manual).
For other bank valve configurations
see RENR6487 (Specifications Manual).
SIDESHIFT
T3
The pilot manifold can also be
accessed with the floor plate
removed. The pilot pressure tap
(T3) is located on the pilot mani-
fold. The pilot manifold routes pilot
oil to and from the loader and
backhoe pilot control valves.
Pilot Manifold
View of pilot controlled backhoe valve with floor plate removed.
The hydraulic oil filter is located below the
machine at the left frame rail. The hydraulic oil
filter bypass switch is mounted to the oil filter
base.
(H) Stick Control Valve
(I) Boom Control Valve
(J) Pilot On/Off Solenoid Valve
(K) Inlet Manifold
(L) A Ports
(M) B Ports
(N) Solenoid for the Sideshift Lock
Outlet manifold (A) Solenoid for the A circuit (H)
Auxiliary control valve (B) Makeup and relief valve (J)
Tilt control valve (C) B pilot line port (K)
Lift control valve (D) A pilot line port (L)
Inlet manifold (E) Priority Valve (M)
Load sensing relief valve (F) Dead engine lower valve (N)
Solenoid for t
he B circuit (G) A ports (P)
B ports (R)
SOS
ECM
Loader Valve
"E" Series sideshift machines have a new slide frame with new externally serviceable slide frame
lock cylinders and reversible/replaceable wear plates (C). The lock cylinders can be serviced in the
field with standard tools. The stabilizers (D) are now externally adjustable. A powered sideshift
(bottom right illustration) is available, which allows the operator to hydraulically shift the backhoe
across the slider.
This illustration shows the optional powered sideshift attachment. The powered sideshift moves the
backhoe across the slider using two hydraulic cylinders (A). Wear pads (B) on the slider and powered
sideshift assembly are serviceable.
A
A
B
CD
To Wheel
Brake
Boost Brake
Valve
From Pilot
Accumulator
To Tank
Master
Cylinder
Slave
Cylinder
ABEDC
T3 Pilot Pressure
32
29
16 17 18
7
7
29
29
32
NOTE: Alpha numeric numbers are represented by the number only on the machine views.
18
31
30
32
18
17
17
36
36
35
35
34
34
33
33
23
22
23
22 25 26
25 26
Hydraulic Oil Filter
Temp Sensor
Filter Bypass
Switch
Temp Sensor
ITEM NAME 432E 434E
1 PUMP GP.
267-2755
2 HYDRAULIC TANK
246-5286
3 TANK GROUP
245-8777
4 COOLER
HYDRAULIC COOLER
5 FILTER
226-9747
6 HMU
210-6240
7
STEER CYLNDERS
7A FRONT
7B
REAR
8
LIFT CYLNDERS
8B PL/IT 214-9373
9
TILT CYLNDERS
9B PL/IT 192-3884
10
MP BUCKET CYL.(OPT)
11
STABILIZER CYLNDERS
11A LH
173-4565
11B RH
173-4565
12 BOOM CYLINDER
268-9049(S)
210-7076
268-9051(S)
246-9884
13 STICK CYL.
14 SWING CYL.
278-1971
15 BUCKET CYL.
210-7085(S) 210-7095(S)
16 E-STICK CYL (OPT).
210-7097(S)
17
VALVE PILOT 2-BANK
17A VALVE PILOT-BODY
223-4713
17B LEVER W/SWITCHES
223-4714
17C LEVER W/DTNT & SWTCH (OPT)
223-4715
18 ACCUMULATOR
226-0420
19 RIDE CNTRL VALVE (OPT)
245-8780
20 RIDE CNTRL ACCMLTR (OPT)
162-3960
21 RIDE CNTR PRES. SWTCH(OPT)
131-9203
22 TEMP. SENSOR (OPT)
TEMP SENSOR
23 DIFF. PRES. SWITCH (OPT)
134-0404
25 COUPLER VALVE (See Volume 2)
231-2615
26 COUPLER CYLINDER (See Volume 2)
190-3085
27
LOADER VALVE (ST)
27A INLET SECTION
269-1080
27E OUTLET MANIFOLD
269-1079
28
LOADER VALVE (PL/IT)
2 BANK
266-2562
3 BANK
266-2563
28B LIFT SECTION
269-1081
28C TILT SECTION
269-1082
28D AUX SECTION
29
LOADER VALVE (EST)
2 BANK
N/A
3 BANK
N/A
29A INLET SECTION
N/A
29C TILT SECTION
N/A
31
BACKHOE VALVE (SIDE SHIFT)
6 BANK
266-2566
7 BANK
266-2567
8 BANK
266-2568
31G BOOM SECTION
269-1071
31H STICK SECTION
269-1072
31J E-STICK SECTION
269-1077
31K OUTLET MANIFOLD
269-1069
32
BACKHOE VALVES (COMMON)
32A INLET MANIFOLD
269-1060
32B STABILIZER SECTION
269-1061
32C SWING SECTION
269-1064
32D BUCKET SECTION
269-1065
32E AUX SECTION
269-1067
32F PATTERN SWITCHING VALVE
257-7724
33 VALVE GP - CUSHION RELIEF
206-3685 (OPT)
34 VALVE GP - PILOT (BACKHOE)
267-2758
35 VALVE GP - PILOT (LOADER)
267-2760
36 MANIFOLD - PILOT
268-0094
N/A
269-1083
COMPONENT LIST
24 ALL WHEEL STEER VALVE
442E 444E
249-6710 LH
249-6711 RH
249-6712 LH
249-6713 RH
210-7101 214-9372
268-9049(S)
210-7076
268-9051(S)
246-9884
210-7083 210-7093 210-7083 210-7093
256-3089 (OPT) 256-3089 (STD)
210-7085(S) 210-7095(S)
N/A
N/A
N/A
N/A
266-2572
266-2573
269-1100
269-1102
214-5097
238-5238
MP BUCKET CYL.
H
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
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 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
RENR6484-03
30 Page, (Dimensions: 39 inches x 28 inches)
THIS SCHEMATIC IS FOR THE 432E, 434E, 422E, AND 444E BACKHOE LOADER
MEDIA NUMBER: RENR6484-03
PART NUMBER: 268-0120, CHANGE: 01, VERSION: -
Components are shown installed on a fully operable machine with the key and engine off and transmission shifter in neutral.
Refer to the appropriate Service Manual for Troubleshooting, Specifications.
A
B
C
D
E
F
G
H
I
A
B
C
D
E
F
G
H
I
12 11 10 9 8 7 6 5 4 3 2 1
12 11 10 9 8 7 6 5 4 3 2 1
PUMP
TANK
6
1
3
2
5
22
23
4
7A
18
FRONT STEER CYL
LOADER VALVE
TILT
LIFT
LOADER VALVE
LEFT JOYSTICK RIGHT JOYSTICK
STABILIZER JOYSTICK
36
34
17C17B17A
BOOSTED BRAKES (REF)
BS
BT
LEFT BRAKE
PEDAL
RIGHT BRAKE
PEDAL
TO REAR AXLE
LEFT WHEEL BRAKE
TO REAR AXLE
RIGHT WHEEL BRAKE
34
DEL
LOADER JOYSTICK
35
FLOAT
RTD
T3
T2
T1
9B
10
26
25
8B
27A
28B
28C
28B
27E
28
SOS
POWERED SIDE-SHIFT OPTION
LOAD SIGNAL LINE
TO TANK
FROM PUMP
SIDESHIFT CYLINDERS
REAR STEER CYL
24
7B
STAB RH
BOOM STICK
BUCKET E-STICK BACKHOE VALVE
DEL
DEL
11B
12
13
14
33
15
16
31K32E31J32D32C
32F
32B
32A
31
SWINGSTAB LH
11A
31G
31H
a1
a3
a2
a1
a3
a2
434E and 444E
29A
21
20
19
