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INTERACTIVE SCHEMATIC

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Cover PageTables

SchematicMachine Views

ComponentConnector

Chassis View

Cab View

Engine View

Features

Options

Bookmarks X

EC-C3EC-C2 E-C60

EC-C1

E-C61

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FUNCTION Zoom In

HOTKEYS (Keyboard Shortcuts)

Zoom OutFit to PageHand Tool

“CTRL” / “+”

KEYS

“CTRL” / “-”“CTRL” / “0” (zero)“SPACEBAR” (hold down)

Find “CTRL” / “F”

PressureSwitch

TemperatureSwitch

LevelSwitch

FlowSwitch Circuit Breaker

T

ELECTRICAL SYMBOLS

Spring(Adjustable)

Variability

FluidConditioner

Pumpor Motor

BASIC HYDRAULICCOMPONENT SYMBOLS

SCHEMATIC SYMBOLS AND DEFINITIONS

HYDRAULIC SYMBOLS - ELECTRICAL

Transducer(Fluid)

Transducer(Gas / Air)

G

Generator ElectricalWire

Pressure Switch

MElectricMotor

Pressure Switch (Adjustable)

TemperatureSwitch

PressureSwitch

TemperatureSwitch

LevelSwitch

FlowSwitch Circuit Breaker

T

ELECTRICAL SYMBOLS

Spring

ControlValves

Restriction Line Restriction(Fixed)

2-SectionPump

MAIN AUX.

Spring(Adjustable)

Variability

Line Restriction(Variable)

PressureCompensation

Pump: Variable andPressure Compensated

Hydraulic PneumaticEnergy Triangles

FluidConditioner

Attachment

Pumpor Motor

BASIC HYDRAULICCOMPONENT SYMBOLS

Line RestrictionVariable 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

BasicSymbol

SpringLoaded

Normal Position

A B

P T

A B

P TShifted Position Infinite Position

Shuttle PilotControlled

VALVES

CHECK

Solenoidor Manual

Solenoidand 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 indicatesthat 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 ofa 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 CompleteInternal

Supply Pressure

RELEASED PRESSURE

REMOTE SUPPLY PRESSURE

PILOT CONTROL

Spring Loaded Gas Charged

ACCUMULATORS

Crossing Joining

LINES

Double ActingSingle Acting

CYLINDERSUnidirectional

Bidirectional

FIXED DISPLACEMENT

VARIABLE DISPLACEMENTNON- COMPENSATED

PUMPS

Unidirectional

Bidirectional

Unidirectional

Bidirectional

FIXED DISPLACEMENT

VARIABLE DISPLACEMENTNON- COMPENSATED

MOTORS

Unidirectional

Bidirectional

TwoPosition

InfinitePositioning

FLOW IN ONEDIRECTION

FLOW ALLOWED INEITHER DIRECTION

ThreePosition

CROSSFLOW

PARALLELFLOW

INTERNAL PASSAGEWAYS

1

2

AG-C4111-7898

L-C123E-5179

9X-1123 ComponentPart Number

Pin or Socket Number

Part Number: forConnector Plug

Harness Identification Letter(s): (A, B, C, AA, AB, AC, ...)

Plug

325-AG135 PK-14

Wire ColorWire Gauge

Receptacle

1

12

2Sure-Seal connector: Typical representationof a Sure-Seal connector. The plug and receptacle contain both pins and sockets.

Deutsch connector: Typical representationof a Deutsch connector. The plug contains all sockets and the receptacle contains all pins.

Fuse (5 Amps)

5A

Harness identification code:This example indicates wire group 325,

wire 135 in harness "AG".

L-C123E-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

UENR3237April 2012

420F and 430F Backhoe LoaderHydraulic System420F:LKH1-UPJWJ1-UP

430F:LNH1-UPRGS1-UP

Printed in U.S.A.© 2012 Caterpillar, All Rights Reserved

COMPONENT LOCATION

Description PartNumber

MachineLocation

SchematicLocation

Pump GP - Implement 307-3069 1 B-4Tank - Hydraulic 358-9301 2 A-5Tank Group - Filter / Breather / Sight Gage 351-5888 3 A-5Cooler - Hydraulic 337-9751 4 B-4Filter - Hydraulic 359-7232 5 B-3Valve HMU - Load Sense Relief 341-7654 6 C-6Cylinder - Front Steer 214-5097 7 B-6

LH: 358-5034RH: 358-5035

Cylinder - Tilt 358-5045 10 B-8Cylinder - MP Bucket (OPT) 185-1839 11 A-8

LH: 291-2681 F-6RH: 291-2682 F-3

420F: 210-7076430F: 246-9884420F: 210-7082430F: 210-7092

LH: 381-8055RH: 381-8054

420F: 210-7088430F: 210-7096

Cylinder - E-Stick 210-7098 17 F-3Accumulator - Pilot 226-0420 18* C-5Valve - Ride Control (OPT) 245-8780 19 C-8Accumulator (OPT) 382-8033 20 C-8Sensor - Ride Control (OPT) 344-7391 21 C-8Sensor - Temp (OPT) 264-4297 22 C-3Switch - Diff Temp (OPT) 134-0404 23* C-3Valve - Coupler (LDR) 359-7228 24 A-8Cylinder - Coupler 178-3713 25 A-8Valve - Loader (PL/IT) 359-7211 27 C-7

6 Bank: 359-72087 Bank: 359-72108 Bank: 359-7212

Valve - Pattern Change 300-4491 29 D-6Valve - Cushion 206-3685 30 F-5Valve - Check (Stab) 359-7213 31 F-3, F-6Valve GP - Pilot (HOE) 359-7227 32 F-8, F-1Valve GP - Pilot 382-4996 33 D-7

STD: 359-7246W/SWITCH: 359-7247

DTNT and SWITCH: 359-7248Manifold - Pilot (BASIC +4) 359-7224 35 D-4Sensor - Pump Discharge 344-7391 36 C-5Valve - Boosted Brake 220-8226 37 D-3Valve - Coupler (HOE) 358-2091 50* A-3Cylinder - Coupler (HOE) 361-1139 51* B-3

Valve GP - Pilot (STAB) 34* E-8

15

16

COMPONENT LOCATIONS

8Cylinder - Lift B-8

F-5

F-4

F-5

F-4

28 F-6

Cylinder - Bucket

Cylinder - Swing

Valve - Backhoe

Cylinder - Stick

Cylinder - Boom

Cylinder - Stab 12

13

14

* COMPONENTS NOT SHOWN

TAP LOCATION

Tap Number Description Schematic Location

T1 PUMP DISCHARGE PRESSURE C-5T2 RIGHT REAR SERVICE BRAKE C-4T3 REAR PARK BRAKES D-5

TAP LOCATIONSPressure, Sampling, Sensor

Components are shown installed on a fully operable machine with the key and engine off, transmission shifterin neutral and with parking brake set.Refer to the appropriate Service Manual for Troubleshooting, Specifications and Systems Operations.

SCHEMATIC PART NUMBER: 362-9207, CHANGE: 01, VERSION: -

THIS SCHEMATIC IS FOR THE 420F AND 430F BACKHOE LOADER HYDRAULIC SYSTEMMEDIA NUMBER: UENR3237

12345678

A

B

C

D

E

F

12345678

A

B

C

D

E

F

HYDRAULIC CIRCUIT COLOR DESCRIPTIONSPILOT PUMP OUTPUTMAIN PUMP OUTPUTLIFT CYLINDER CIRCUITBUCKET CYLINDER CIRCUITLOAD SENSE CIRCUITSTEERING CIRCUITSTICK CYLINDER CIRCUITSUPPLY LINEAUX CIRCUITBOOM CYLINDER CIRCUITTILT CYLINDER CIRCUITLOADER VALVE CIRCUITDRAIN / RETURN LINESTABILIZER CYLINDER CIRCUITSWING CYLINDER CIRCUITE-STICK CYLINDER CIRCUITCOUPLER CIRCUIT (HOE)BOOSTED BRAKE OIL CIRCUIT

LINE PATTERNS

Drain / Return Lines

Component Group

Pilot / Load Sensing Pressure

Pressure Line

CALLOUTS

Taps (Pressure, Sampling, Sensor - by letter)YY

(52) VALVE GP - CONTROL138-1234

Callout Number(Machine Location from

Component LocationsTable)

ComponentName

Part Number

OPERATOR LEFT JOYSTICK

STABILIZER JOYSTICK

OPERATOR RIGHT JOYSTICK

T2

T1

T3

(8) CYLINDER - LIFT

(10) CYLINDER - TILT

(11) CYLINDER -MP BUCKET (OPT)

(25) CYLINDER - COUPLER

(24) VALVE - COUPLER (LDR)

(27) VALVE - LOADER (PL/IT)

(21) SENSOR - RIDE CONTROL (OPT)

(20) ACCUMULATOR - OPTIONAL

(19) VALVE - RIDE CONTROL (OPT)

(28) VALVE - BACKHOE

(32) VALVE GP - PILOT (HOE)

(34) VALVE GP - PILOT (STAB)

(33) VALVE GP - PILOT

(12) CYLINDER - STAB

(31) VALVE -CHECK (STAB)

(3) TANK GROUP - FILTER / BREATHER / SIGHT GAGE

(2) TANK - HYDRAULIC

(7) CYLINDER - FRONT STEER

(18) ACCUMULATOR - PILOT

(36) SENSOR -PUMP DISCHARGE

(6) VALVE HMU - LOAD SENSE RELIEF

(29) VALVE - PATTERN CHANGE

(13) CYLINDER - BOOM

(1) PUMP GP - IMPLEMENT

(4) COOLER - HYDRAULIC

(5) FILTER - HYDRAULIC

(23) SWITCH - DIFF PRESS(OPTIONAL)

(22) SENSOR - TEMP(OPTIONAL)

(35) MANIFOLD - PILOT (BASIC +4)

(14) CYLINDER - STICK(15) CYLINDER - SWING

(16) CYLINDER - BUCKET

(30) VALVE - CUSHION

(37) VALVE - BOOSTED BRAKE

(12) CYLINDER - STAB

(31) VALVE - CHECK (STAB)

(32) VALVE GP - PILOT (HOE)

(17) CYLINDER - E STICK(OPT)

(50) VALVE - COUPLER(HOE)

(51) CYLINDER -COUPLER (HOE)

351-5888

358-9301

337-9751

307-3069

214-5079

359-7232

134-0404

264-4297

220-8226

359-7224

226-0420

344-7391

341-7654

300-4491

359-7227

210-7098

291-2682

359-7213

210-7082210-7092

420F:430F:381-8054

LH:RH:

381-8055

206-3685

291-2681 210-7076246-9884

420F:430F:

359-7213

6 BANK: 359-7208

359-7227

359-7247359-7248

W / SWITCH:DTNT and SWITCH:

358-2091

347-2223

BACKHOE COUPLER

T7

P7

HAB

HAA

B8A8

210-7082210-7092

420F:430F:

7 BANK: 359-72108 BANK: 359-7212

359-7246STD:

TA

FRONT STEER CYL.

RH STAB BOOM SWING BUCKET STICK LH STAB E-STICK

A4 B4B3 A6 B6A1 B1

RS2

RS1

BA

BB R4

R2

SB

SA

LS1

LS2 EA

EB

J1

J2 T2 T3 J3

T1

P ACC DIAG

OPERATORLEFT

OPERATORRIGHT

LAAEB

LABEA

LS2LS1RS2RS1

L1L3L2L4

R2R4R3R1

SBBABB SA

L4R1 R3 L2

A3

BRK

LEFTBRAKEPEDAL

TO REAR AXLELEFT WHEEL

BRAKE

TO REAR AXLERIGHT WHEEL

BRAKE

SU

A2 B2 A5 B5 A7 B7

R L

T7P7

T6

P6

L1

L3

RIGHTBRAKEPEDAL

AUX

D

DLS

LIFT

TILT

AUX

ACC

R

T

PS

H

LB

LA

TB

LAB

LAA

P

A1

B1

A2

B2

A3

B3

LIFT

TILT

AUX

359-7211

344-7391

382-8033

245-8780

344-7391

358-5045

185-1839

178-3713

359-7228

382-4996

TA

TILTLIFT

LOADER JOYSTICK

TBLALB

FRONT VIEW

2524

108

4

REAR MACHINE VIEW

33 32 16

15

14

13

12

11

BOOM VIEW - WITH E-STICK

17

FRAME VIEW (From Top)

T2

T1

37

36

30

28

27

22

21

20

197

6

5

32

1

REAR FRAME VIEW

T335

31

29