diagrama hidraulico 420e caterpillar

7/22/2019 Diagrama Hidraulico 420E CATERPILLAR

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R E N R 6 4 8 3 V O L 1

3 0 P a g e

ONE POSITION TWOPOSITION THREE POSITION

V ENT ED P RE SS UR IZ ED RETURNABOVE FLUIDLEVEL RETURNBELOW FLUIDLEVEL

LINES CROSSING LINES JOINING

TWO-WAY THREE-WAY FOUR-WAY

S P RI N G C O NT R OL V AL VE S RESTRICTION LINE RESTRICTION

(FIXED)

2-SECTIONPUMP

MAINAUX.

SPRING

(ADJUSTABLE)

VARIABILITY LINE RESTRICTION

(VARIABLE)

LINE RESTRICTIONVARIABLE andPRESSURE

COMPENSATED

PRESSURE

COMPENSATION

PUMP:VARIABLE andPRESSURE COMPENSATED

ENERGY TRIANGLES

HYDRAUL IC PNEUMA TIC

MEASUREMENT

PRESSURE TEMPERATURE FLOW

ROTATING SHAFTS

UNIDIRECTIONAL BIDIRECTIONAL

PUSH-PULL LEVER PEDALGENERAL MANUAL PUSH BUTTON SPRING

MANUAL CONTROL SYMBOLS

HYDRAULICMOTORS

FIXED

DISPLACEMENTVARIABLE DISPLACEMENT

NON-COMPENSATED

UNIDIRECTIONAL

BIDIRECTIONAL

HYDRAULICPUMPS

FLUIDSTORAGE RESERVOIRS

CROSSING ANDJOINING LINES

VALVE ENVELOPES VALVE PORTS

BASICCOMPONENT SYMBOLS

FLUIDCONDITIONERPUMP orMOTOR

FLUID POWER SYMBOLS

FIXED

DISPLACEMENT

VARIABLE DISPLACEMENT

NON-COMPENSATED

UNIDIRECTIONAL

BIDIRECTIONAL

VALVES

PILOT CONTROL SYMBOLSRELEASEDPRESSURE

EXTERNALRETURN INTERNALRETURN

REMOTE SUPPLY PRESSURE

SIMPLIFIED COMPLETE INTERNAL

SUPPLY PRESSURE

ACCUMULATORS

SPRING LOADED GAS CHARGED

SOLENOIDorMANUAL

SOLENOIDandPILOT

SOLENOIDandPILOTorMANUAL

COMBINATIONCONTROLS

SOLENOID SERVO THERMAL DETENT

HYDRAULICANDPNEUMATICCYLINDERS

DOUBLE ACTINGSINGLE ACTING

BASICSYMBOL

SPRINGLOADED

CHECK VALVES

TWO

POSITION

INFINITEPOSITIONING

FLOWINONEDIRECTION

FLOWALLOWEDINEITHER DIRECTION

THREEPOSITION

CROSSFLOW

PARALLELFLOW

INTERNAL PASSAGEWAYS

NORMALPOSITION

AB

PT

AB

PT

SHIFTEDPOSIT ION INFINITE POSITION

CONTROL VALVES

ATTACHMENT

MANUALSHUTOFF

SHUTTLE PIL OTCONTROLLED

Hydraulic Symbols (Electrical)

Electrical Symbols Table

325-AG135PK-14

CircuitIdentificationNumber

W ir e Co lo r W ir e Ga ug e

Harnessidentificationcode Thisexampleindicateswire135inharness"AG".

325-PK-14

WireGauge

WireColor

CircuitNumber

Identification

Wire Number Identification Codes

CurrentStandard

Previous Standard

Electrical Schematic Example Hydraulic Schematic Example

325-PK

WireColorCircuitNumber

Identification

B A

Wire

Wire

(EXAMPLE VALVE)

CurrentStandard

Transducer(Fluid)

Transducer(Gas /Air)

G

Generator

ElectricalWirePressureS witch

MElectricMotor

PressureSwitch(Adjustable)

TemperatureSwitch

T

PressureSymbol

TemperatureSymbol

LevelSymbol

FlowSymbol

Electrical Symbols (Electrical)

Volume 1: Single Tilt

RENR6483May2006

420E and 430E Backhoe Loader Hydraulic System

420E:KMW1-UPHLS1-UP

430E:DDT1-UPEAT1-UP

©2006Caterpillar

AllRightsReserved

PrintedinU.S.A.

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

28

3130

T ap D es c ri p t io n

T1 PumpDischarge

T2 LoadSense

SOS OilSampling

TAP LOCATIONS

( A)OutletManifold

(B)LeftStabilizerControlValve(C)AuxiliaryControlValve(D)ExtendableStickControlValve

(E)BucketControlValve(F)SwingControlValve(G)StickControlValve

A B C D E F G

H

I

BACKHOE VALVE 30

The420E/430E machinesareequippedwithapilotcontrolledbackhoevalvethatisvisiblewiththefloorplateattherearofthecabremoved.

Thisillustrationshowsa eightbankbackhoevalveina 420E BackhoeLoader.Thecomponentsinthebackhoevalveare:

SOSImplementand

SteeringP ump

HYDRAULIC OIL FILTER

SOS FilterBypass Switch

5

The 420E/430E machinescan be equipped witha

mechanically controlledloadervalve or a pilotcontrolledloadervalveasshowninthisillustration.

Theloader valveis accessed frombelowthe floorplate.Theloadercontrolvalvegroupcontains:

LOADER VALVE

E

2728

DC

B

A

Travelathighspeedsoverroughterraincausesbucketmovement.TheoptionalRideControlSystemactsas ashockabsorberbyabsorbingbucketforces, whichstabilizethe machine.

TheRideControlSystemcomponentsinclude;ridecontrolrelay(A),ridecontrolsolenoids(B), ridecontrol accumulator (C),and ridecontrolpressureswitch(D).

Twosolenoidsarenowusedon the"E"SeriesmachinesRideControlSystem.

TheRide Control System, onmachineswiththe optionalautoshifttransmission,is controlledbythe MachineECM. TheMachineECMmonitorsthepositionoftheridecontrolswitchanddetermineswhentooperatetheride controlsystem.

RIDE CONTROL

B

A

C

D

IMPLEMENT / STEERING PUMP

The implement andsteeringpump on the420E and430E machinesis similartothe "D"Seriesmachines,butnowincludesa torque

control solenoid (not visible).The torquecontrolsolenoid providesan additionalpumpsetting.

Theimplementandsteeringpumpislocatedbelowthefloorplatein thecab. Thepumpcontrolvalve (H) containsa torque control

spooladjustmentscrew(B) anda flowcom-pensatoradjustmentscrew(A). Theadjust-mentscrewsand theloadsensingpressuretap(T2)areaccessiblefromthecab.

1

F

NOTE: 420E/430Emachineswithamechanicallycontrolledloadervalveora pilot controlledloader

valveusethesameinlet manifold.

Viewof mechanicallycontrolledloadervalvewithfloorplateremoved.

LoaderValve

Theseillustrationsshowtheimplementandsteeringpumpoutofthemachine.Thefollowingcomponentsarevisible:

Torquecontroladjustment( A), Flowcompensatoradjustment(B), Loadsensingpressuretap (T2), Inletport(C),Casedrainport(D),Torquecontrolsolenoid(E), Dischargepressuretap(T1), Torquelimiter(F), Outletport(G)

BC 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

The420E/430E machinesareequippedwithhydraulicallyassistedmastercylinders,whichdecreasestheamountofpedaleffortwhenbraking.Thisillustrationshowstheboostedbrakesvalvegroup,whichusesoilfromthepilotaccumulatortoaddboosttothemastercylinder.Thehydraulicforcemultipliesthe

pedaleffortsotheoperatorcangetmorebrakingforcewithlesseffort.

Thebrakeboostvalvesareconnectedtothemastercylinder(A)ateachbrakepedal(B).Oilentersthemastercylinderthroughthesupplyhose(C)andexitsthemastercylinderthroughthereturnhose(D).Theoilflowstotheservicebrakesthroughthehoses(E)atthebottomofthemastercylinder.

Themastercylinderscanberemovedfromthemachinefrominsidetheoperator'scompartment.

Thisillustrationshowsasectionalviewoftheboostedbrakevalvegroup.Whenthebrakepedalisdepressed,theboostbrakevalvemovestotheleftandinletoilfromthepilotmanifoldis directed

tothe mastercylinder.

BOOSTED BRAKES

J

K

Drain

EIGHT BANK VALVE (PILOT OPERATED)

For other bank valveconfigurations seeRENR6487(Specifications Manual).

For other bank valveconfigurationsseeRENR6487(Specifications Manual).

SIDESHIFT SLIDE LOCKS

T3

The pilot manifold canalsobeaccessed with the floor plateremoved. The pilotpressuretap

(T3)is locatedonthepilotmani-fold.Thepilotmanifoldroutespilotoilto andfromthe loaderand

backhoepilot controlvalves.

Pilot Manifold

Viewof pilot controlledbackhoevalvewithfloorplateremoved.

The hydraulic oil filter is located belowthemachineat theleftframerail.The hydraulicoil

filterbypass switch ismountedto theoil filterbase.

(H)BoomControlValve

(I)RightStabilizerControlValve(J)PilotOn/OffSolenoidValve(K)InletManifold

(L)APorts(M)BPorts

Outletmanifold( A) SolenoidfortheA circuit(H)

Auxiliarycontrolvalve (B) Makeupandreliefvalve(J)

Tiltcontrolvalve(C) B p il ot l in eport (K)

Liftcontrolvalve(D) A p il ot l in eport (L)

Inletmanifold(E) P ri or it yV al ve (M)

Loadsensingreliefvalve(F) Deadenginelowervalve(N)

SolenoidfortheB circuit(G) A ports (P)

B ports (R)

SOS

ECM

Sideshiftmachinesfeaturea boom(A)thatcanbe shiftedtodifferentpositionsalonga frame(B).

Lockpistons(D)areusedtolocktheboomtotheframerails.Lockpistonsolenoids,locatedon thebackhoevalve outletmanifold, actuatethe lockpistons.

Thestabilizers(C)areusedto raiseandlowerthemachine.Sideshiftandcenterpivotmachinesusethesametypeofcontrolvalvestooperatethestabilizers.

A

ToWheelBrake

BoostBrakeValve

FromPilotAccumulator

ToTank

MasterCylinder

SlaveCylinder

A BE D C T3 PilotPressure

32

1617 18

7

7

29

29

32

NOTE:A lphanumericnumbersarerepresentedby thenumberonlyon themachineviews.

18

31 30

32

18

17

17

36

36

35

35

34

34

33

33

23

22

23

22 25 26

2526

HydraulicOilFilter

TempSensor

FilterBypassSwitch

TempSensor

B

D

C

L

M

ITEM NAME 420E 430E

1 P UMP G P. 267-2755

2 HY DR AUL I C TANK 246-5286

3 T AN K G RO UP 245-8777

4 C OO LE R HYDRAULICCOOLER

5 F ILT ER 226-9747

6 HMU 210-6240

7STEERC YLNDERS

7 A F RO NT

7B REAR

8

L IFTCYLNDERS

8A ST 228-3509

8B P L/ IT 228-3505

9

TILTCYLNDERS

9A ST 200-7128

9B P L/IT 192-3884

10 MPBUCKETCYL.(OPT)

11

STABILIZERC YLNDERS

11A L H 262-7049

11B R H 262-7050

12 BOOMCYLINDER268-9049(S)

210-7076268-9051(S)246-9884

13 STICK CYL. 210-7081(S) 210-7091

1 4 S WI NG CY L . 278-1971

1 5 B UCKE T C YL . 210-7087(S) 210-7095(S)

16 E-STICKCYL(OPT). 210-7097(S)

17

VALVEPILOT 2-BANK

17A VALVEPILOT-BODY 223-4713

17B LEVERW/SWITCHES 223-4714

17C LEVERW/DTNT& SWTCH(OPT) 223-4715

18 ACCUMULATOR 226-0420

19 RIDECNTRLVALVE(OPT) 245-8780

20 RIDECNTRLACCMLTR(OPT) 162-3960

21 RIDECNTRPRES.SWTCH(OPT) 131-9203

22 TEMP.SENSOR(OPT) TEMPSENSOR

23 DIFF.PRES.SWITCH(OPT) 134-0404

25 COUPLERVALVE (SeeVolume2) 231-2615

26 COUPLERCYLINDER (SeeVolume2) 190-3085

27

LOADERVALVE(ST)

2BANK 266-2552

3BANK 266-2553

27A INLETSECTION 269-1080

27B LIFTSECTION 269-1091

27C TILTSECTION 269-1092

27D AUXSECTION 269-1093

27E OUTLETMANIFOLD 269-1079

28

LOADERVALVE(PL /IT)

2BANK N/A

3BANK 266-2563



28D AUXSECTION

30

BACKHOEVALVE(CP)

6BANK 266-2556

7BANK 266-2557

8BANK 266-2558

30G BOOMSECTION 269-1062

30H STICKSECTION 269-1063

30J E-STICKSECTION 269-1066

30K OUTLETMANIFOLD 269-1059

32

BACKHOEVALVES(COMMON)

32A INLETMANIFOLD 269-1060

32B STABILIZERSECTION 269-1061

32C SWINGSECTION 269-1064

32D BUCKETSECTION 269-1065

3 2E AUXS EC TI ON 269-1067

32F PATTERNSWITCHINGVALVE 257-7724

3 3 VAL VE G P -C US HI ONR E L IE F 206-3685(STD)

34 VALVEGP -PILOT(BACKHOE) 267-2758

3 5 VAL VE G P -PI L OT ( L OADE R ) 267-2760

3 6 M ANIFO LD - PI LO T 268-0094

N/A

N/A

N/A

N/A

N/A

COMPONENT LIST

ImplementandSteeringPump

A

B

T2C

LoaderValve

H



R E N R 6 4 8 3 V O L 1

3 0 P a g e , C o l o r 2

LINE PATTERNS

Drain/ReturnLines

ComponentGroup

Pilot/LoadSensingPressure

PressureLine

Attachment

AirLine

CALLOUTS

Taps(Pressure,Sampling,Sensor)byletter

Componentsbynumber

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

AUXILIARY CIRCUIT (BACKHOE VALVE)

E-STICK CYLINDER CIRCUIT

BOOM CYLINDER CIRCUIT

STABILIZER CYLINDER CIRCUIT

BOOSTED BRAKE OIL CIRCUIT

LIFT CYLINDER CIRCUIT

TILT CYLINDER CIRCUIT

AUXILIARY CIRCUIT (LOADER VALVE)

THIS SCHEMATIC IS FOR THE 420E AND430E BACKHOE LOADERS

PART#:268-0120CHG01 VOLUME 1OF 2

Componentsareshown installedona fullyoperablemachinewith thekeyand engineoffandtransmissionshifter inneutral.

Referto theappropriateServiceManual forTroubleshooting,Specificationsand SystemsOperations

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

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.

420E/430E ST

AUX.

TILT

LIFT

LOADER VALVE

LEFT JOYSTICK RIGHT JOYSTICKSTABILIZER JOYSTICK

36

BOOSTED BRAKES (REF)

BS BT

LEFTBRAKEPEDAL

RIGHTBRAKEPEDAL

TOREAR AXLE

LEFTWHEEL BRAKE

TOREAR AXLE

RIGHTWHEEL BRAKE

DEL

27

T3

T2

T1

11B 12 13

14

33

15 1611A

30K 32B32E30J32D32C

32F

30G32B32A

18

30

27A

27B

27C

27D

10

9A8A

21

20

19

17C17A34 34

30H

SOS

6

7A

27E



R E N R 6 4 8 3 V O L 2

3 0 P a g e

ONE POSITION TWOPOSITION THREE POSITION

V ENT ED P RE SS UR IZ ED RETURNABOVE FLUIDLEVEL RETURNBELOW FLUIDLEVEL

LINES CROSSING LINES JOINING

TWO-WAY THREE-WAY FOUR-WAY

S P RI N G C O NT R OL V AL VE S RESTRICTION LINE RESTRICTION

(FIXED)

2-SECTIONPUMP

MAINAUX.

SPRING

(ADJUSTABLE)

VARIABILITY LINE RESTRICTION

(VARIABLE)

LINE RESTRICTIONVARIABLE andPRESSURE

COMPENSATED

PRESSURE

COMPENSATION

PUMP:VARIABLE andPRESSURE COMPENSATED

ENERGY TRIANGLES

HYDRAUL IC PNEUMA TIC

MEASUREMENT

PRESSURE TEMPERATURE FLOW

ROTATING SHAFTS

UNIDIRECTIONAL BIDIRECTIONAL

PUSH-PULL LEVER PEDALGENERAL MANUAL PUSH BUTTON SPRING

MANUAL CONTROL SYMBOLS

HYDRAULICMOTORS

FIXED

DISPLACEMENTVARIABLE DISPLACEMENT

NON-COMPENSATED

UNIDIRECTIONAL

BIDIRECTIONAL

HYDRAULICPUMPS

FLUIDSTORAGE RESERVOIRS

CROSSING ANDJOINING LINES

VALVE ENVELOPES VALVE PORTS

BASICCOMPONENT SYMBOLS

FLUIDCONDITIONERPUMP orMOTOR

FLUID POWER SYMBOLS

FIXED

DISPLACEMENT

VARIABLE DISPLACEMENT

NON-COMPENSATED

UNIDIRECTIONAL

BIDIRECTIONAL

VALVES

PILOT CONTROL SYMBOLSRELEASEDPRESSURE

EXTERNALRETURN INTERNALRETURN

REMOTE SUPPLY PRESSURE

SIMPLIFIED COMPLETE INTERNAL

SUPPLY PRESSURE

ACCUMULATORS

SPRING LOADED GAS CHARGED

SOLENOIDorMANUAL

SOLENOIDandPILOT

SOLENOIDandPILOTorMANUAL

COMBINATIONCONTROLS

SOLENOID SERVO THERMAL DETENT

HYDRAULICANDPNEUMATICCYLINDERS

DOUBLE ACTINGSINGLE ACTING

BASICSYMBOL

SPRINGLOADED

CHECK VALVES

TWO

POSITION

INFINITEPOSITIONING

FLOWINONEDIRECTION

FLOWALLOWEDINEITHER DIRECTION

THREEPOSITION

CROSSFLOW

PARALLELFLOW

INTERNAL PASSAGEWAYS

NORMALPOSITION

AB

PT

AB

PT

SHIFTEDPOSIT ION INFINITE POSITION

CONTROL VALVES

ATTACHMENT

MANUALSHUTOFF

SHUTTLE PIL OTCONTROLLED

Hydraulic Symbols (Electrical)

Electrical Symbols Table

325-AG135PK-14

CircuitIdentificationNumber

W ir e Co lo r W ir e Ga ug e

Harnessidentificationcode Thisexampleindicateswire135inharness"AG".

325-PK-14

WireGauge

WireColor

CircuitNumber

Identification

Wire Number Identification Codes

CurrentStandard

Previous Standard

Electrical Schematic Example Hydraulic Schematic Example

325-PK

WireColorCircuitNumber

Identification

B A

Wire

Wire

(EXAMPLE VALVE)

CurrentStandard

Transducer(Fluid)

Transducer(Gas /Air)

G

Generator

ElectricalWirePressureS witch

MElectricMotor

PressureSwitch(Adjustable)

TemperatureSwitch

T

PressureSymbol

TemperatureSymbol

LevelSymbol

FlowSymbol

Electrical Symbols (Electrical)

Volume 2: Parallel Lift / Integrated Tool Carrier

RENR6483May2006

420E and 430E Backhoe Loader Hydraulic System

420E:KMW1-UPHLS1-UP

430E:DDT1-UPEAT1-UP

©2006Caterpillar

AllRightsReserved

PrintedinU.S.A.

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

28

3130

T ap D es c ri p t io n

T1 PumpDischarge

T2 LoadSense

SOS OilSampling

TAP LOCATIONS

BACKHOE VALVE 30

SOSImplementand

SteeringP ump

HYDRAULIC OIL FILTER

SOS FilterBypass Switch

5

The 420E/430E machinescan be equipped witha

mechanically controlledloadervalve or a pilotcontrolledloadervalveasshowninthisillustration.

Theloader valveis accessed frombelowthe floorplate.Theloadercontrolvalvegroupcontains:

LOADER VALVE

E

2728

DC

B

A

Travelathighspeedsoverroughterraincausesbucketmovement.TheoptionalRideControlSystemactsas ashockabsorberbyabsorbingbucketforces, whichstabilizethe machine.

TheRideControlSystemcomponentsinclude;ridecontrolrelay(A),ridecontrolsolenoids(B), ridecontrol accumulator (C),and ridecontrolpressureswitch(D).

Twosolenoidsarenowusedon the"E"SeriesmachinesRideControlSystem.

TheRide Control System, onmachineswiththe optionalautoshifttransmission,is controlledbythe MachineECM. TheMachineECMmonitorsthepositionoftheridecontrolswitchanddetermineswhentooperatetheride controlsystem.

RIDE CONTROL

B

A

C

D

IMPLEMENT / STEERING PUMP 1

F

NOTE: 420E/430Emachineswithamechanicallycontrolledloadervalveora pilot controlledloader

valveusethesameinlet manifold.

Viewof mechanicallycontrolledloadervalvewithfloorplateremoved.

LoaderValve

Theseillustrationsshowtheimplementandsteeringpumpoutofthemachine.Thefollowingcomponentsarevisible:

Torquecontroladjustment( A), Flowcompensatoradjustment(B), Loadsensingpressuretap (T2), Inletport(C),Casedrainport(D),Torquecontrolsolenoid(E), Dischargepressuretap(T1), Torquelimiter(F), Outletport(G)

BC 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

The420E/430E machinesareequippedwithhydraulicallyassistedmastercylinders,whichdecreasestheamountofpedaleffortwhenbraking.Thisillustrationshowstheboostedbrakesvalvegroup,whichusesoilfromthepilotaccumulatortoaddboosttothemastercylinder.Thehydraulicforcemultipliesthe

pedaleffortsotheoperatorcangetmorebrakingforcewithlesseffort.

Thebrakeboostvalvesareconnectedtothemastercylinder(A)ateachbrakepedal(B).Oilentersthemastercylinderthroughthesupplyhose(C)andexitsthemastercylinderthroughthereturnhose(D).Theoilflowstotheservicebrakesthroughthehoses(E)atthebottomofthemastercylinder.

Themastercylinderscanberemovedfromthemachinefrominsidetheoperator'scompartment.

Thisillustrationshowsasectionalviewoftheboostedbrakevalvegroup.Whenthebrakepedalisdepressed,theboostbrakevalvemovestotheleftandinletoilfromthepilotmanifoldis directed

tothe mastercylinder.

BOOSTED BRAKES

Drain

For other bank valveconfigurations seeRENR6487(Specifications Manual).

For other bank valveconfigurationsseeRENR6487(Specifications Manual).

T3

The pilot manifold canalsobeaccessed with the floor plateremoved. The pilotpressuretap

(T3)is locatedonthepilotmani-fold.Thepilotmanifoldroutespilotoilto andfromthe loaderand

backhoepilot controlvalves.

Pilot Manifold

Viewof pilot controlledbackhoevalvewithfloorplateremoved.

The hydraulic oil filter is located belowthemachineat theleftframerail.The hydraulicoil

filterbypass switch ismountedto theoil filterbase.

Outletmanifold( A) SolenoidfortheA circuit(H)

Auxiliarycontrolvalve (B) Makeupandreliefvalve(J)

Tiltcontrolvalve(C) B p il ot l in eport (K)

Liftcontrolvalve(D) A p il ot l in eport (L)

Inletmanifold(E) P ri or it yV al ve (M)

Loadsensingreliefvalve(F) Deadenginelowervalve(N)

SolenoidfortheB circuit(G) A ports (P)

B ports (R)

SOS

ECM

ToWheelBrake

BoostBrakeValve

FromPilotAccumulator

ToTank

MasterCylinder

SlaveCylinder

A BE D C

T3 PilotPressure

32

1617 18

7

7

29

29

32

NOTE:A lphanumericnumbersarerepresentedby thenumberonlyon themachineviews.

18

31 30

32

18

17

17

36

36

35

35

34

34

33

33

23

22

23

22 25 26

2526

HydraulicOilFilter

TempSensor

FilterBypassSwitch

TempSensor

SIDESHIFT SLIDE LOCKS

Sideshiftmachinesfeaturea boom(A)thatcanbe shiftedtodifferentpositionsalongaframe(B).

Lockpistons(D)areusedtolocktheboomtotheframerails.Lockpistonsolenoids,locatedonthebackhoevalve outletmanifold, actuatethel ockpistons.

Thestabilizers(C)areusedtoraiseand lowerthemachine.Sideshiftandcenterpivotmachinesusethesametypeofcontrolvalvestooperatethestabilizers.

A

B

D

C

( A

)OutletManifold(B)LeftStabilizerControlValve

(C)Auxiliary ControlValve(D)ExtendableStickControlValve(E)BucketControlValve

(F)SwingControlValve(G)StickControlValve

A B C D E F G

H

I

The420E/430E machinesareequippedwithapilotcontrolledbackhoevalvethatisvisiblewiththefloorplateattherearofthecabremoved.

Thisillustrationshowsa eightbankbackhoevalveina 420E BackhoeLoader.Thecomponentsinthebackhoevalveare:

J

K

EIGHT BANK VALVE (PILOT OPERATED)

(H

)BoomControlValve(I)RightStabilizerControlValve

(J)PilotOn/OffSolenoidValve(K)InletManifold(L)APorts

(M)BPorts

L

M

ITEM NAME 420E 430E

1 P UMP G P. 267-2755

2 HY DR AUL IC T ANK 246-5286

3 T AN K G RO UP 245-8777

4 C OO LE R HYDRAULICCOOLER

5 F ILT ER 226-9747

6 HMU 210-6240

7STEERCYLNDERS

7 A F RO NT

7B REAR

8

L IFTCYLNDERS

8A ST 228-3509

8B P L/ IT 228-3505

9

TILTCYLNDERS

9A ST 200-7128

9B P L/IT 192-3884

10 MPBUCKETCYL.(OPT)

11

STABILIZERCYLND ERS

11A L H 262-7049

11B R H 262-7050

12 BOOMCYLINDER268-9049(S)210-7076

268-9051(S)246-9884

13 STICK CYL. 210-7081(S) 210-7091

1 4 S WI NG C Y L. 278-1971

1 5 B UCKE T C YL . 210-7087(S) 210-7095(S)

16 E-STICKCYL(OPT). 210-7097(S)

17

VALVEPILOT 2-BANK

17A VALVEPILOT-BODY 223-4713

17B LEVERW/SWITCHES 223-4714

17C LEVERW/DTNT& SWTCH(OPT) 223-4715

18 ACCUMULATOR 226-0420

19 RIDECNTRLVALVE(OPT) 245-8780

20 RIDECNTRLACCMLTR(OPT) 162-3960

21 RIDECNTRPRES.SWTCH(OPT) 131-9203

22 TEMP.SENSOR(OPT) TEMPSENSOR

23 DIFF.PRES.SWITCH(OPT) 134-0404

25 COUPLERVALVE (SeeVolume2) 231-2615

26 COUPLERCYLINDER (SeeVolume2) 190-3085

27

LOADERVALVE(ST)

2BANK 266-2552

3BANK 266-2553

27A INLETSECTION 269-1080



27D AUXSECTION 269-1093

27E OUTLETMANIFOLD 269-1079

28

LOADERVALVE(PL /IT)

2BANK N/A

3BANK 266-2563



28D AUXSECTION

30

BACKHOEVALVE(CP)

6BANK 266-2556

7BANK 266-2557

8BANK 266-2558

30G BOOMSECTION 269-1062

30H STICKSECTION 269-1063

30J E-STICKSECTION 269-1066

30K OUTLETMANIFOLD 269-1059

32

BACKHOE VALVES(COMMON)

32A INLETMANIFOLD 269-1060

32B STABILIZERSECTION 269-1061

32C SWINGSECTION 269-1064

32D BUCKETSECTION 269-1065

3 2E AUXS EC TI ON 269-1067

32F PATTERNSWITCHINGVALVE 257-77243 3 VAL VE G P -C US HI ONR E L IE F 206-3685(STD)

34 VALVEGP -PILOT(BACKHOE) 267-2758

3 5 VAL VE G P -PI L OT ( L OADE R ) 267-2760

3 6 M ANIFO LD - PI LO T 268-0094

N/A

N/A

N/A

N/A

N/A

COMPONENT LIST

The implement andsteeringpump on the420E and430E machinesis similartothe "D"Seriesmachines,butnowincludesa torquecontrol solenoid (not visible).The torque

controlsolenoid providesan additionalpumpsetting.

Theimplementandsteeringpumpislocatedbelowthefloorplatein thecab. Thepumpcontrolvalve(H) containsa torque controlspooladjustmentscrew(B) anda flowcom-

pensatoradjustmentscrew(A). Theadjust-mentscrewsand theloadsensingpressuretap(T2)areaccessiblefromthecab.

ImplementandSteeringPump

A

B

T2C

LoaderValve

H



R E N R 6 4 8 3 - 0

0 V O L 2

3 0 P a g e , C o l o r 2

LINE PATTERNS

Drain/ReturnLines

ComponentGroup

Pilot/LoadSensingPressure

PressureL ine

Attachment

AirLine

CALLOUTS

Taps(Pressure,Sampling,Sensor)byletter

Componentsbynumber

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

AUXILIARY CIRCUIT (BACKHOE VALVE)

E-STICK CYLINDER CIRCUIT

BOOM CYLINDER CIRCUIT

STABILIZER CYLINDER CIRCUIT

BOOSTED BRAKE OIL CIRCUIT

LIFT CYLINDER CIRCUIT

TILT CYLINDER CIRCUIT

AUXILIARY CIRCUIT (LOADER VALVE)

THIS SCHEMATIC IS FOR THE 420E AND430E BACKHOE LOADERS

PART#:268-0120CHG01 VOLUME 2OF 2

Componentsareshown installedona fullyoperablemachinewiththe keyandengineoffandtransmissions hifterinneutral.

Referto theappropriateService ManualforTroubleshooting,Specifications andSystemsOperations

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

STAB RH BOOM STICK SWING BUCKET E-STICK AUX. STAB LH

HMU

PUMP

TANK

BACKHOE VALVE

11B 12 13

14

3315 16

11A

30K 32B32E30J32D32C

32F

30G32B32A

6

1

3

2

5

22

23

4

7A

18

FRONT STEER CYL.

30

420E/430E PL/IT

AUX.

TILT

LIFT

LOADER VALVE

LEFT JOYSTICK RIGHT JOYSTICKSTABILIZER JOYSTICK

36

3417C17B17A

BOOSTED BRAKES (REF)

BS BT

LEFTBRAKEPEDAL

RIGHTBRAKEPEDAL

TOREAR AXLE

LEFTWHEEL BRAKE

TOREAR AXLE

RIGHTWHEELBRAKE

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

diagrama hidraulico 420e caterpillar

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