420E Sist Hidr
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UENR0231 VOL 1 of 2 30 Page, (Dimensions: 39 inches x 28 inches) 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 Pressure Symbol Temperature Symbol Level Symbol Flow Symbol Electrical Symbols (Electrical) 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 PEDAL GENERAL 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 T Volume 1 of 2: Single Lift UENR0231 March 2010 420E and 430E Backhoe Loader Hydraulic System 420E: DJL1-UP DAN1-UP 430E: MXB1-UP SWC1-UP 11A 11B 30 14 2-3 6 1 5 27 29 7 COMPONENT LOCATIONS 2 1 5 6 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 19 20 21 20 21 27 27 28 28 29 Tap Description T1 Pump Discharge T2 Load Sense SOS Oil Sampling TAP LOCATIONS (A) Outlet Manifold (B) Left Stabilizer Control Valve (C) Auxiliary Control Valve (D) Extendable Stick Control Valve (E) Bucket Control Valve (F) Swing Control Valve (G) Stick Control Valve A B C D E F G H I BACKHOE VALVE 29 SOS Implement and Steering Pump HYDRAULIC OIL FILTER SOS Filter Bypass Switch 5 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 420E 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. 1 F NOTE: 420E machines with a mechanically controlled loader valve or a pilot controlled loader valve use the same inlet manifold. 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 T2 T1 T2 T1 The 420E machines are equipped with hydraulically assisted master cylinders. 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 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 SLIDE LOCKS 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) Boom Control Valve (I) Right Stabilizer Control Valve (J) Pilot On/Off Solenoid Valve (K) Inlet Manifold (L) A Ports (M) B Ports 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 the B circuit (G) A ports (P) B ports (R) SOS ECM Sideshift machines feature a boom (A) that can be shifted to different positions along a frame (B). Lock pistons (D) are used to lock the boom to the frame rails. Lock piston solenoids, located on the backhoe valve outlet manifold, actuate the lock pistons. The stabilizers (C) are used to raise and lower the machine. Sideshift and center pivot machines use the same type of control valves to operate the stabilizers. A To Wheel Brake Boost Brake Valve From Pilot Accumulator To Tank Master Cylinder Slave Cylinder A B E D C T3 Pilot Pressure 16 17 18 7 7 29 29 NOTE: Alpha numeric numbers are represented by the number only on the machine views. 18 29 18 17 17 33 33 32 32 31 31 33 33 23 22 23 22 25 26 25 26 Hydraulic Oil Filter Temp Sensor Filter Bypass Switch Temp Sensor B D C L M ITEM NAME PART NUMBER 1 PUMP GP. 267-2755 2 HYDRAULIC TANK 297-1233 3 TANK GROUP 297-1232 4 COOLER HYDRAULIC COOLER 5 FILTER 226-9747 6 HMU 210-6240 STEER CYLINDER 7 FRONT 8 LIFT CYLINDERS 8A ST 228-3509 8B PL/IT 228-3505 9 TILT CYLINDERS 9A ST 200-7128 9B PL/IT 192-3884 10 MP BUCKET CYL.(OPT) 11 STABILIZER CYLINDERS 11A LH 262-7049 11B RH 262-7050 12 BOOM CYLINDER 268-9049(S) 210-7076 13 STICK CYL. 210-7081(S) 14 SWING CYL. 278-1971 15 BUCKET CYL. 210-7087(S) 16 E-STICK CYL (OPT). 210-7097(S) 17 VALVE PILOT 2-BANK 17A VALVE PILOT-BODY 223-4713 17B 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) 304-5696 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) 2 BANK 266-2552 3 BANK 266-2553 27A INLET SECTION 269-1080 27B LIFT SECTION 269-1091 27C TILT SECTION 269-1092 27D AUX SECTION 269-1093 27E OUTLET MANIFOLD 269-1079 28 LOADER VALVE (PL/IT) 3 BANK 266-2563 28B LIFT SECTION 269-1081 28C TILT SECTION 269-1082 28D AUX SECTION 29 BACKHOE VALVE (CP) 6 BANK 266-2556 7 BANK 266-2557 8 BANK 266-2558 29A BOOM SECTION 269-1062 29B SWING SECTION 269-1064 29C BUCKET SECTION 269-1065 29D STICK SECTION 269-1063 BACKHOE VALVES (COMMON) 30 31 32 33 34 VALVE AS - SHUTTLE N/A 35 PRESSURE SENSOR AESC HYDRAULIC PRESSURE SENSOR VALVE GP - CUSHION RELIEF 206-3685 (STD) VALVE GP - PILOT (BACKHOE) 267-2758 VALVE GP - PILOT (LOADER) 267-2760 MANIFOLD - PILOT 268-0094 185-1839 N/A 214-5097 269-1083 COMPONENT LIST Implement and Steering Pump A B T2 C Loader Valve H E-STICK SECTION 269-1066 STABILIZER SECTION 269-1061 29G AUX SECTION 269-1067 29H 29E 29F OUTLET MANIFOLD 269-1059 29J INLET MANIFOLD 269-1060 29K PATTERN SWITCHING VALVE 257-7724 HYDRAULIC COMPONENTS
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Sistema Hidraulico de Retro Cat 420E
Transcript of 420E Sist Hidr
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Hydraulic Symbols (Electrical)
Electrical Symbols Table
325-AG135 PK-14
Circuit IdentificationNumber
Wire Color Wire Gauge
Harness identification codeThis example indicateswire 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 ColorCircuit Number Identification
B A
Wire
Wire
(EXAMPLE VALVE)
Current Standard
Transducer(Fluid)
Transducer(Gas / Air)
G
Generator
Electrical WirePressure Switch
MElectric Motor
Pressure Switch (Adjustable)
Temperature Switch
PressureSymbol
TemperatureSymbol
LevelSymbol
FlowSymbol
Electrical Symbols (Electrical)
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 RESTRICTIONVARIABLE and PRESSURE
COMPENSATED
PRESSURECOMPENSATION
PUMP: VARIABLE andPRESSURE COMPENSATED
ENERGY TRIANGLESHYDRAULIC PNEUMATIC
MEASUREMENT
PRESSURE TEMPERATURE FLOW
ROTATING SHAFTS
UNIDIRECTIONAL BIDIRECTIONAL
PUSH-PULL LEVER PEDALGENERAL MANUAL PUSH BUTTON SPRING
MANUAL CONTROL SYMBOLS
HYDRAULIC MOTORS
FIXEDDISPLACEMENT
VARIABLE DISPLACEMENTNON-COMPENSATED
UNIDIRECTIONAL
BIDIRECTIONAL
HYDRAULIC PUMPS
FLUID STORAGE RESERVOIRS
CROSSING AND JOINING LINES
VALVE ENVELOPES VALVE PORTS
BASIC COMPONENT SYMBOLS
FLUID CONDITIONERPUMP or MOTOR
FLUID POWER SYMBOLS
FIXEDDISPLACEMENT
VARIABLE DISPLACEMENTNON-COMPENSATED
UNIDIRECTIONAL
BIDIRECTIONAL
VALVES
PILOT CONTROL SYMBOLSRELEASED PRESSURE
EXTERNAL RETURN INTERNAL RETURN
REMOTE SUPPLY PRESSURE
SIMPLIFIED COMPLETE INTERNALSUPPLY 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
BASICSYMBOL
SPRINGLOADED
CHECK VALVES
TWOPOSITION
INFINITEPOSITIONING
FLOW IN ONEDIRECTION
FLOW ALLOWED INEITHER DIRECTION
THREEPOSITION
CROSSFLOW
PARALLELFLOW
INTERNAL PASSAGEWAYS
NORMAL POSITION
A B
P T
A B
P TSHIFTED POSITION INFINITE POSITION
CONTROL VALVES
ATTACHMENT
MANUAL SHUTOFF
SHUTTLE PILOTCONTROLLED
T
Volume 1 of 2: Single Lift
UENR0231March 2010
420E and 430E Backhoe LoaderHydraulic System420E:DJL1-UPDAN1-UP
430E:MXB1-UPSWC1-UP
11A
11B
30
14
2-3
6
1
5
27
29
7
COMPONENT LOCATIONS
21
5 6
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
2829
Tap DescriptionT1 Pump DischargeT2 Load Sense
SOS Oil Sampling
TAP LOCATIONS
(A) Outlet Manifold(B) Left Stabilizer Control Valve(C) Auxiliary Control Valve(D) Extendable Stick Control Valve(E) Bucket Control Valve(F) Swing Control Valve(G) Stick Control Valve
A B C D E F G
H
I
BACKHOE VALVE 29
SOSImplement and Steering Pump
HYDRAULIC OIL FILTER
SOS Filter Bypass Switch
5
The loader valve is accessed from below the floor plate. The loader control valve group contains:
LOADER VALVE
E
27 28
DC
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 420E 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.
1
F
NOTE: 420E machines with a mechanically controlled loader valve or a pilot controlled loader valve use the same inlet manifold.
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
T2
T1
T2
T1
The 420E machines are equipped with hydraulically assisted master cylinders. 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
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 SLIDE LOCKS
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) Boom Control Valve(I) Right Stabilizer Control Valve(J) Pilot On/Off Solenoid Valve(K) Inlet Manifold(L) A Ports(M) B Ports
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 the B circuit (G) A ports (P)
B ports (R)
SOS
ECM
Sideshift machines feature a boom (A) that can be shifted to different positions along a frame (B). Lock pistons (D) are used to lock the boom to the frame rails. Lock piston solenoids, located on the backhoe valve outlet manifold, actuate the lock pistons.
The stabilizers (C) are used to raise and lower the machine. Sideshift and center pivot machinesuse the same type of control valves to operate the stabilizers.
A
To Wheel Brake
Boost Brake Valve
From PilotAccumulatorTo Tank
Master Cylinder
SlaveCylinder
A BE D C
T3 Pilot Pressure
16 17 18
7
7
29
29
NOTE: Alpha numeric numbers are represented by the number only on the machine views.
18
29 18
17
17
33
33
32
32
31
31
33
33
2322
2322 25 26
25 26
Hydraulic Oil Filter
Temp Sensor
Filter BypassSwitch
Temp Sensor
B
DC
L
M
ITEM NAME PART NUMBER1 PUMP GP. 267-2755
2 HYDRAULIC TANK 297-1233
3 TANK GROUP 297-1232
4 COOLER HYDRAULIC COOLER
5 FILTER 226-9747
6 HMU 210-6240
STEER CYLINDER7 FRONT
8LIFT CYLINDERS
8A ST 228-3509
8B PL/IT 228-3505
9TILT CYLINDERS
9A ST 200-7128
9B PL/IT 192-3884
10 MP BUCKET CYL.(OPT)
11STABILIZER CYLINDERS
11A LH 262-7049
11B RH 262-7050
12 BOOM CYLINDER 268-9049(S)210-7076
13 STICK CYL. 210-7081(S)
14 SWING CYL. 278-1971
15 BUCKET CYL. 210-7087(S)
16 E-STICK CYL (OPT). 210-7097(S)
17
VALVE PILOT 2-BANK17A VALVE PILOT-BODY 223-4713
17B 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) 304-5696
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)2 BANK 266-2552
3 BANK 266-2553
27A INLET SECTION 269-1080
27B LIFT SECTION 269-1091
27C TILT SECTION 269-1092
27D AUX SECTION 269-1093
27E OUTLET MANIFOLD 269-1079
28
LOADER VALVE (PL/IT)3 BANK 266-2563
28B LIFT SECTION 269-1081
28C TILT SECTION 269-1082
28D AUX SECTION
29
BACKHOE VALVE (CP)
6 BANK 266-2556
7 BANK 266-2557
8 BANK 266-2558
29A BOOM SECTION 269-1062
29B SWING SECTION 269-1064
29C BUCKET SECTION 269-1065
29D STICK SECTION 269-1063
BACKHOE VALVES (COMMON)
30
31
32
33
34 VALVE AS - SHUTTLE N/A
35 PRESSURE SENSOR AESC HYDRAULIC PRESSURE SENSOR
VALVE GP - CUSHION RELIEF 206-3685 (STD)
VALVE GP - PILOT (BACKHOE) 267-2758
VALVE GP - PILOT (LOADER) 267-2760
MANIFOLD - PILOT 268-0094
185-1839N/A
214-5097
269-1083
COMPONENT LIST
Implement and Steering Pump
AB
T2C
Loader Valve
H
E-STICK SECTION 269-1066
STABILIZER SECTION 269-1061
29G AUX SECTION 269-1067
29H
29E
29F
OUTLET MANIFOLD 269-1059
29J INLET MANIFOLD 269-1060
29K PATTERN SWITCHING VALVE 257-7724
HYDRAULIC COMPONENTS
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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
THIS SCHEMATIC IS FOR THE 420E AND 430E BACKHOE LOADER (SINGLE TILT) HYDRAULIC SYSTEMVOLUME 1 of 2: SINGLE TILT PART NUMBER: 297-5426, CHANGE: 01, VERSION: SComponents are shown installed on a fully operable machine.
Refer to the appropriate Service Manual for Troubleshooting, Specifications and Systems Operations.
DRAIN / RETURN LINE
HYDRAULIC CIRCUIT COLOR DESCRIPTIONSIMPLEMENT AND STEERING PUMP CIRCUIT
SWING CYLINDER CIRCUIT
STEERING CYLINDER CIRCUIT
PILOT OIL CIRCUIT
BUCKET CYLINDER CIRCUIT
STICK CYLINDER CIRCUIT
LOAD SENSE CIRCUITSUPPLY LINE
AUXILIARY CIRCUIT (BACKHOE VALVE)E-STICK CYLINDER CIRCUIT
BOOM CYLINDER CIRCUITSTABILIZER CYLINDER CIRCUIT
BOOSTED BRAKE OIL CIRCUIT
LIFT CYLINDER CIRCUITTILT CYLINDER CIRCUITAUXILIARY CIRCUIT (LOADER VALVE)
12345678
A
B
C
D
E
F
12345678
A
B
C
D
E
F
STAB RH BOOM STICK SWING BUCKET E-STICK AUX. STAB LH
HMU
PUMP
TANK
BACKHOE VALVE
1
3
2
5
22
23
4
FRONT STEER CYL.
AUX.
TILT
LIFT
LOADER VALVE
LEFT JOYSTICK RIGHT JOYSTICKSTABILIZER JOYSTICK
36
BOOSTED BRAKES (REF)
BS BT
LEFT BRAKE PEDAL
RIGHT BRAKE PEDAL
TO REAR AXLE LEFT WHEEL BRAKE
TO REAR AXLE RIGHT WHEEL BRAKE
DEL
27
T3
T2
T1
11B 12 13
14
3315 16
11A
30K32B32E30J32D32C
32F
30G32B32A
18
30
27A
27B
27C
27D
10
9A8A
21
20
19
17C 17A 34 34
30H
SOS
6
7A
27E
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Hydraulic Symbols (Electrical)
Electrical Symbols Table
325-AG135 PK-14
Circuit IdentificationNumber
Wire Color Wire Gauge
Harness identification codeThis example indicateswire 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 ColorCircuit Number Identification
B A
Wire
Wire
(EXAMPLE VALVE)
Current Standard
Transducer(Fluid)
Transducer(Gas / Air)
G
Generator
Electrical WirePressure Switch
MElectric Motor
Pressure Switch (Adjustable)
Temperature Switch
PressureSymbol
TemperatureSymbol
LevelSymbol
FlowSymbol
Electrical Symbols (Electrical)
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 RESTRICTIONVARIABLE and PRESSURE
COMPENSATED
PRESSURECOMPENSATION
PUMP: VARIABLE andPRESSURE COMPENSATED
ENERGY TRIANGLESHYDRAULIC PNEUMATIC
MEASUREMENT
PRESSURE TEMPERATURE FLOW
ROTATING SHAFTS
UNIDIRECTIONAL BIDIRECTIONAL
PUSH-PULL LEVER PEDALGENERAL MANUAL PUSH BUTTON SPRING
MANUAL CONTROL SYMBOLS
HYDRAULIC MOTORS
FIXEDDISPLACEMENT
VARIABLE DISPLACEMENTNON-COMPENSATED
UNIDIRECTIONAL
BIDIRECTIONAL
HYDRAULIC PUMPS
FLUID STORAGE RESERVOIRS
CROSSING AND JOINING LINES
VALVE ENVELOPES VALVE PORTS
BASIC COMPONENT SYMBOLS
FLUID CONDITIONERPUMP or MOTOR
FLUID POWER SYMBOLS
FIXEDDISPLACEMENT
VARIABLE DISPLACEMENTNON-COMPENSATED
UNIDIRECTIONAL
BIDIRECTIONAL
VALVES
PILOT CONTROL SYMBOLSRELEASED PRESSURE
EXTERNAL RETURN INTERNAL RETURN
REMOTE SUPPLY PRESSURE
SIMPLIFIED COMPLETE INTERNALSUPPLY 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
BASICSYMBOL
SPRINGLOADED
CHECK VALVES
TWOPOSITION
INFINITEPOSITIONING
FLOW IN ONEDIRECTION
FLOW ALLOWED INEITHER DIRECTION
THREEPOSITION
CROSSFLOW
PARALLELFLOW
INTERNAL PASSAGEWAYS
NORMAL POSITION
A B
P T
A B
P TSHIFTED POSITION INFINITE POSITION
CONTROL VALVES
ATTACHMENT
MANUAL SHUTOFF
SHUTTLE PILOTCONTROLLED
T
420E:DJL1-UPDAN1-UP
430E:MXB1-UPSWC1-UP
Volume 2 of 2: Parallel Lift
UENR0231March 2010
420E and 430E Backhoe LoaderHydraulic System
© 2010 CaterpillarAll Rights Reserved
Printed in U.S.A.
11A
11B
30
14
2-3
6
1
5
27
29
7
COMPONENT LOCATIONS
21
5 6
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
2829
Tap DescriptionT1 Pump DischargeT2 Load Sense
SOS Oil Sampling
TAP LOCATIONS
SOSImplement and Steering Pump
HYDRAULIC OIL FILTER
SOS Filter Bypass Switch
5
The loader valve is accessed from below the floor plate. The loader control valve group contains:
LOADER VALVE
E
27 28
DC
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 1
F
NOTE: 420E machines with a mechanically controlled loader valve or a pilot controlled loader valve use the same inlet manifold.
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
T2
T1
T2
T1
Drain
For other bank valve configurations see RENR6487 (Specifications Manual).
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.
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 the B circuit (G) A ports (P)
B ports (R)
SOS
ECM
T3 Pilot Pressure
16 17 18
7
7
29
29
NOTE: Alpha numeric numbers are represented by the number only on the machine views.
18
29 18
17
17
33
33
32
32
31
31
33
30
2322
2322 25 26
25 26
Hydraulic Oil Filter
Temp Sensor
Filter BypassSwitch
Temp Sensor
The implement and steering pump on the 420E 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
AB
T2C
Loader Valve
H
ITEM NAME PART NUMBER1 PUMP GP. 267-2755
2 HYDRAULIC TANK 297-1233
3 TANK GROUP 297-1232
4 COOLER HYDRAULIC COOLER
5 FILTER 226-9747
6 HMU 210-6240
STEER CYLINDER7 FRONT
8LIFT CYLINDERS
8A ST 228-3509
8B PL/IT 228-3505
9TILT CYLINDERS
9A ST 200-7128
9B PL/IT 192-3884
10 MP BUCKET CYL.(OPT)
11STABILIZER CYLINDERS
11A LH 262-7049
11B RH 262-7050
12 BOOM CYLINDER 268-9049(S)210-7076
13 STICK CYL. 210-7081(S)
14 SWING CYL. 278-1971
15 BUCKET CYL. 210-7087(S)
16 E-STICK CYL (OPT). 210-7097(S)
17
VALVE PILOT 2-BANK17A VALVE PILOT-BODY 223-4713
17B 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) 304-5696
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)2 BANK 266-2552
3 BANK 266-2553
27A INLET SECTION 269-1080
27B LIFT SECTION 269-1091
27C TILT SECTION 269-1092
27D AUX SECTION 269-1093
27E OUTLET MANIFOLD 269-1079
28
LOADER VALVE (PL/IT)3 BANK 266-2563
28B LIFT SECTION 269-1081
28C TILT SECTION 269-1082
28D AUX SECTION
29
BACKHOE VALVE (CP)
6 BANK 266-2556
7 BANK 266-2557
8 BANK 266-2558
29A BOOM SECTION 269-1062
29B SWING SECTION 269-1064
29C BUCKET SECTION 269-1065
29D STICK SECTION 269-1063
BACKHOE VALVES (COMMON)
30
31
32
33
34 VALVE AS - SHUTTLE N/A
35 PRESSURE SENSOR AESC HYDRAULIC PRESSURE SENSOR
VALVE GP - CUSHION RELIEF 206-3685 (STD)
VALVE GP - PILOT (BACKHOE) 267-2758
VALVE GP - PILOT (LOADER) 267-2760
MANIFOLD - PILOT 268-0094
185-1839N/A
214-5097
269-1083
COMPONENT LIST
E-STICK SECTION 269-1066
STABILIZER SECTION 269-1061
29G AUX SECTION 269-1067
29H
29E
29F
OUTLET MANIFOLD 269-1059
29J INLET MANIFOLD 269-1060
29K PATTERN SWITCHING VALVE 257-7724
(A) Outlet Manifold(B) Left Stabilizer Control Valve(C) Auxiliary Control Valve(D) Extendable Stick Control Valve(E) Bucket Control Valve(F) Swing Control Valve(G) Stick Control Valve
A B C D E F G
H
I
BACKHOE VALVE 29
The 420E machines are equipped with hydraulically assisted master cylinders. 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
K
EIGHT BANK VALVE (PILOT OPERATED)
For other bank valve configurations see RENR6487 (Specifications Manual).
SIDESHIFT SLIDE LOCKS
(H) Boom Control Valve(I) Right Stabilizer Control Valve(J) Pilot On/Off Solenoid Valve(K) Inlet Manifold(L) A Ports(M) B Ports
Sideshift machines feature a boom (A) that can be shifted to different positions along a frame (B). Lock pistons (D) are used to lock the boom to the frame rails. Lock piston solenoids, located on the backhoe valve outlet manifold, actuate the lock pistons.
The stabilizers (C) are used to raise and lower the machine. Sideshift and center pivot machinesuse the same type of control valves to operate the stabilizers.
A
To Wheel Brake
Boost Brake Valve
From PilotAccumulatorTo Tank
Master Cylinder
SlaveCylinder
A BE D C
B
DC
L
M
HYDRAULIC COMPONENTS
UE
NR
0231 V
OL
2 o
f 2
30
Pa
ge
, (D
ime
ns
ion
s:
39
in
ch
es
x 2
8 i
nc
he
s)
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
THIS SCHEMATIC IS FOR THE 420E AND 430E BACKHOE LOADER (PARALLEL LIFT) HYDRAULIC SYSTEMVOLUME 2 of 2: PARALLEL LIFT PART NUMBER: 297-5426, CHANGE: 01, VERSION: SComponents are shown installed on a fully operable machine.
Refer to the appropriate Service Manual for Troubleshooting, Specifications and Systems Operations.
DRAIN / RETURN LINE
HYDRAULIC CIRCUIT COLOR DESCRIPTIONSIMPLEMENT AND STEERING PUMP CIRCUIT
SWING CYLINDER CIRCUIT
STEERING CYLINDER CIRCUIT
PILOT OIL CIRCUIT
BUCKET CYLINDER CIRCUIT
STICK CYLINDER CIRCUIT
LOAD SENSE CIRCUITSUPPLY LINE
AUXILIARY CIRCUIT (BACKHOE VALVE)E-STICK CYLINDER CIRCUIT
BOOM CYLINDER CIRCUITSTABILIZER CYLINDER CIRCUIT
BOOSTED BRAKE OIL CIRCUIT
LIFT CYLINDER CIRCUITTILT CYLINDER CIRCUITAUXILIARY CIRCUIT (LOADER VALVE)
12345678
A
B
C
D
E
F
12345678
A
B
C
D
E
F
STAB RH BOOM STICK SWING BUCKET E-STICK AUX. STAB LH
HMU
PUMP
TANK
BACKHOE VALVE
11B 12 13
14
3315 16
11A
30K32B32E30J32D32C
32F
30G32B32A
6
1
3
2
5
22
23
4
7A
18
FRONT STEER CYL.
30
AUX.
TILT
LIFT
LOADER VALVE
LEFT JOYSTICK RIGHT JOYSTICKSTABILIZER JOYSTICK
36
3417C 17B 17A
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
21
20
19
27A
28B
28C
28B
27E28
30H
SOS
