UENR3236-01May 2013

420F and 430F Backhoe LoaderHydraulic System420F:LTG1-UPSKR1-UP

430F:RDF1-UPLDY1-UP

Printed in U.S.A.© 2013 Caterpillar, All Rights Reserved

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)

PUMP(2 - SECTION)

SPRING(ADJUSTABLE)

VARIABILITY LINE RESTRICTION(VARIABLE)

PRESSURECOMPENSATION

PUMP(VARIABLE & PRESSURE

COMPENSATED)

MEASUREMENT

PRESSURE TEMPERATURE FLOW

ROTATING SHAFTS

UNIDIRECTIONAL BIDIRECTIONAL

PUSH - PULL LEVER PEDALGENERAL MANUAL PUSH BUTTON SPRING

FIXEDDISPLACEMENT

VARIABLE DISPLACEMENTNON-COMPENSATED

UNIDIRECTIONAL

BIDIRECTIONAL

VALVE ENVELOPES VALVE PORTS

FLUID CONDITIONERPUMP OR MOTOR

FLUID POWER SYMBOLS

UNIDIRECTIONAL

BIDIRECTIONAL

RELEASED PRESSURE

EXTERNAL RETURN INTERNAL RETURN

REMOTE SUPPLY PRESSURE

SIMPLIFIED

HYDRAULIC PUMPS

ACCUMULATORS

SPRING LOADED GAS CHARGED

SOLENOID OR MANUAL

SOLENOID & PILOT

SOLENOID &PILOT OR MANUAL

SOLENOID SERVO THERMAL DETENT

HYDRAULIC & PNEUMATIC CYLINDERS

DOUBLE ACTINGSINGLE ACTING

BASICSYMBOL

SPRINGLOADED

CHECK VALVES

2 POSITIONINFINITE

POSITIONING

FLOW IN ONEDIRECTION

FLOW INEITHER

DIRECTION

3 POSITION

CROSSFLOW

PARALLELFLOW

INTERNAL PASSAGEWAYS

NORMAL POSITION

A B

P T

A B

P TSHIFTED POSITION INFINITE POSITION

CONTROL VALVES

ATTACHMENT

MANUAL SHUTOFF

SHUTTLE PILOTCONTROLLED

MAIN AUX

LINE RESTRICTION(VARIABLE & PRESSURE

COMPENSATED)

MANUAL CONTROL SYMBOLS

HYDRAULIC MOTORS

FLUID STORAGE RESERVOIRS

CROSSING & JOINING LINES

VALVES

PILOT CONTROL SYMBOLS

COMBINATION CONTROLS

BASIC COMPONENT SYMBOLS

ENERGY TRIANGLESHYDRAULIC PNEUMATIC

INTERNALSUPPLY PRESSURE

COMPLETE

FIXEDDISPLACEMENT

VARIABLE DISPLACEMENTNON-COMPENSATED

HYDRAULIC SYMBOLS (ELECTRICAL)

ELECTRICAL SYMBOLS TABLE

325-AG135 PK-14

HARNESS IDENTIFICATION CODE THIS EXAMPLEINDICATES WIRE 135 IN HARNESS “AG”

325-PK-14

WIRE GAUGE

WIRE COLOR

CIRCUIT NUMBERIDENTIFICATION

WIRE NUMBER IDENTIFICATION CODES

CURRENT STANDARD

PREVIOUS STANDARD

ELECTRICAL SCHEMATIC EXAMPLE HYDRAULIC SCHEMATIC EXAMPLE

325-PK

WIRE COLORCIRCUIT NUMBER

IDENTIFICATION

B

WIRE

WIRE

(EXAMPLE VALVE)

CURRENT STANDARD

TRANSDUCER(FLUID)

MELECTRIC MOTORTRANSDUCER

(GAS / AIR)

G

GENERATOR

PRESSURE SWITCH ELECTRICAL WIREPRESSURE SWITCH(ADJUSTABLE)

TEMPERATURESWITCH

PRESSURESWITCH

TEMPERATURESWITCH

LEVELSWITCH

FLOWSWITCH

ELECTRICAL SYMBOLS (ELECTRICAL)

A

CIRCUIT NUMBERIDENTIFICATION

WIRECOLOR

WIRE GAUGE UE

NR

3236-0

13

0 P

ag

e,

(Dim

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sio

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: 3

9 i

nc

he

s x

28

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es

)

FRONT VIEW

REAR MACHINE VIEWS

UNDER CAB VIEW

30 28

5

37

19

27

1

9 4

72 3

15

13

14

11

16

12

328

31

29

35

6

36

20

22

21

T1

T3

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

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 358-5044 9 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 - 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-1

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

Cylinder - Stick

Cylinder - Boom

Cylinder - Stab 12

Valve GP - Pilot (STAB)

Valve - Backhoe

Cylinder - Bucket

Cylinder - Swing

28 F-6

34* E-8

F-5

F-4

F-5

F-4

13

14

15

16

COMPONENT LOCATIONS

8Cylinder - LIFT B-8

* COMPONENTS NOT SHOWN

BOOM WITH E-STICK

17

T2

UE

NR

3236-0

13

0 P

ag

e,

(Dim

en

sio

ns

: 3

9 i

nc

he

s x

28

in

ch

es

)

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: UENR3236-01

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

(12) CYLINDER - STAB

(31) VALVECHECK (STAB)

(28) VALVE - BACKHOE

(32) VALVE GP - PILOT (HOE)

(34) VALVE GP - PILOT (STAB)

(27) VALVE - LOADER (PL/IT)

(21) SENSORRIDE CONTROL (OPT)

(20) ACCUMULATOR - OPTIONAL

(19) VALVE - RIDE CONTROL (OPT)

(8) CYLINDER - LIFT

(11) CYLINDERMP BUCKET (OPT)

(9) CYLINDER - TILT

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

(2) TANK - HYDRAULIC

(7) CYLINDER - FRONT STEER

(18) ACCUMULATOR - PILOT

(36) SENSORPUMP DISCHARGE

(6) VALVE HMU - LOAD SENSE RELIEF

(29) VALVE - PATTERN CHANGE

(1) PUMP GP - IMPLEMENT

(35) MANIFOLD - PILOT (BASIC +4)

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

(16) CYLINDER - BUCKET

(30) VALVE - CUSHION

(13) CYLINDER - BOOM

(4) COOLER - HYDRAULIC

(5) FILTER - HYDRAULIC

(23) SWITCH - DIFF PRESS(OPTIONAL)

(22) SENSOR - TEMP(OPTIONAL)

(37) VALVE - BOOSTED BRAKE

(32) VALVE GP - PILOT (HOE)

(17) CYLINDER - E STICK(OPT)

(12) CYLINDER - STAB

(31) VALVE - CHECK (STAB)

(50) VALVE - COUPLER(HOE)

(51) CYLINDERCOUPLER (HOE)

T2

T1

T3

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

359-7211

344-7391

382-8033

245-8780

185-1839

359-7227

210-7098

291-2682

359-7213

210-7082210-7092

420F:430F:

381-8054LH: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

D

DLS

LIFT

TILT

AUX

FRONT STEER CYL.

ACC

R

T

PS

H

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

OPERATOR LEFT JOYSTICK

OPERATORLEFT

OPERATORRIGHT

STABILIZER JOYSTICK

P

LAAEB

LABEA

LS2LS1RS2RS1

L1L3L2L4

R2R4R3R1

SBBABB SA

L4R1 R3 L2

A1

B1

A2

B2

A3

B3

A3

BRK

LEFTBRAKEPEDAL

TO REAR AXLELEFT WHEEL

BRAKE

TO REAR AXLERIGHT WHEEL

BRAKE

SU

LIFT

AUX

A2 B2 A5 B5 A7 B7

R L

T7P7

T6

P6

L1

L3

OPERATOR RIGHT JOYSTICK

RIGHTBRAKEPEDAL

AUX

HAB

HAA

B8A8

210-7082210-7092

420F:430F:

7 BANK: 359-72108 BANK: 359-7212

359-7246STD:

358-5044

358-5035LH:RH:

358-5034