INTERACTIVE SCHEMATIC

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Electrical Symbols

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Tap Views

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Bookmarks X

EC-C3EC-C2 E-C60

EC-C1

E-C61

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

KENR8398-04April 2012

793F Off-Highway TruckHydraulic SystemSND1-UPSSP1-UP

Page 1 of 2COMPONENT LOCATION

Description PartNumber

MachineLocation

SchematicLocation

Accumulator Gp - Brake (ACC1) 291-1546 1 I-5Accumulator Gp - Brake (ACC2) 291-1546 2 I-4Accumulator Gp - Steering 308-2856 3 F-11Breather 157-7911 4 D-7Connector - Orifice 311-6676 6 G-4, G-5Cylinder Gp - Telescoping, Hoist 295-5708 7 H-12Filter - Oil, Adv Eff., Breather 4T-6788 8 D-5Filter Gp - Case Drain 290-2569 9 D-7Filter Gp - Fan / Steering Return 339-9706 10 A-8Filter Gp - Oil, Brake 290-2567 11 F-5Filter Gp - Oil, Hoist / Brk Cooling 339-9702 12 I-9Fitting - Orifice 1 8X-7851 13 G-4, G-6Fitting - Orifice 2 8X-7851 14 F-8Fitting - Orifice 3 8X-7851 15 E-11Motor Gp - Fan 240-7790 16 E-9Pump / Motor Gp - Brake Release 5T-1060 17 I-8Pump Gp - Fan / Steering 291-7263 18 B-9Pump Gp - Hoist / Brake 310-4846 19 F-6Pump Gp - Metering (HMU) 9T-1318 20 D-3Screen - Pmp Brng Flushing Return 247-8298 21 C-7Screen Gp - Hoist Lines 6E-5472 22 H-10Slack Adjustor Gp - Front 205-0560 23 G-2Slack Adjustor Gp - Rear 205-0560 24 G-14Valve Gp - Check 1 332-7350 25 C-7Valve Gp - Check 2 6E-4701 26 I-5Valve Gp - Check, Brk Rel Pump 123-4750 27 I-8Valve Gp - Check, Brk Rel, El Pump 123-4750 28 I-4Valve Gp - Cntrl, Hoist / Brk Cooling 247-1437 29 I-12Valve Gp - Makeup 183-7170 30 E-9Valve Gp - Sol / Mnfld 198-6577 31 F-8Valve Gp - Sol / Rlf, Str Acc. 272-9849 32 E-11Valve Gp - Steering 9T-8931 33 F-3

Control Gp - Foot Brake 315-5037 34 H-3Cylinder Gp - Steering 9T-8912 35 F-3

Mechanical Drive (Hydraulic Arrangement 278-8418)

Page 2 of 2COMPONENT LOCATION

Description PartNumber

MachineLocation

SchematicLocation

Filter Gp - Oil, RAX 333-6434 36 F-12Manifold Gp - Control, RAX 299-3258 37 E-12Motor Gp - Brake Cooling 198-6041 38 C-4Motor Gp - RAX 202-9940 39 D-12Pump Gp - Brake Cooling 197-8885 40 C-5Pump Gp - RAX 214-1555 41 D-12Screen As - Hydr. Oil Cooler 149-2754 42 I-9Tank Gp - Hydraulic 288-5701 43 B-5Valve / Mtg Gp - Cntrl, Brks, Std Whl 285-5630 44 H-4Valve / Mtg Gp - Cntrl, Brks, XL Whl 283-9559 45 H-4Valve Gp - Relief, Brake Oil Cooler 6E-5855 46 D-5Valve Gp - Traction Control 222-4744 47 I-7

Accumulator Gp - Steering (PED) 308-3556 48 F-11Cooler Gp - RAX Oil Cooler 320-8196 49Motor Gp - RAX Oil Cooler Fan 307-1504 50Plug As - Rear Axle Cooler 242-7114 51 F-12Valve Gp - Press. Rdc, Rad Fan Cntrl 226-0835 52 D-9

Core As - Oil Cooler, Brake 290-2729 53 J-8Core As - Oil Cooler, Brake 336-9641 54 J-9Core Gp - Oil Cooler, Steering 199-6683 55 A-8Sensor Gp - Press., Brake Pump 221-3405 56 I-5Sensor Gp - Press., Brk Acc. (ACC1) 221-3405 57 I-5Sensor Gp - Press., Brk Acc. (ACC2) 221-3405 58 I-3Sensor Gp - Press., Differential Oil 221-3415 59 F-12Sensor Gp - Press., Rr Brk Oil, LH 221-3410 60 I-7Sensor Gp - Press., Rr Brk Oil, RH 221-3410 61 E-9Sensor Gp - Press., Steering Acc. 221-3405 62 E-11Sensor Gp - Press., Steering Pump 221-3405 63 F-8Sensor Gp - Speed, Clng Pmp Drive 186-0131 64 C-5Sensor Gp - Speed, Fan 186-0131 65 H-7Switch As - Press., Serv. Brake (Frnt) 128-5091 67 G-4Switch As - Press., Serv. Brake (Rear) 128-5091 68 G-6

Attachments

Misc. Ref.

G-11G-11

TAP LOCATION

Description TapNumber

SchematicLocation

Brake Pump Filter Outlet Pressure R F-5

Brake Pump Pressure N F-6

Case Drain Return Filter Pressure P2 C-7

Front Slack Adjuster Pressure I1 G-1

Front, Left Parking Brake Release Press. J1 J-1

Front, Right Parking Brake Release Press. J2 D-1

Hoist Control Pilot Pressure L1 H-11

Hoist Control Pilot Pressure L2 G-11

Hoist Pump 1 Pressure M1 F-6

Hoist Pump 2 Pressure M2 F-6

Left, Front Wheel, Brake Cooling Input Press. K1 J-2

Left, Front Wheel, Brake Cooling Output Press. K2 I-1

Left, Rear Wheel, Brake Cooling Input Press. K5 J-13

Left, Rear Wheel, Brake Cooling Output Press. K6 I-14

Left, Rear Wheel, Traction Pilot Pressure S1 I-7

Purge Point for Comissioning P1 H-3

Radiator Fan Pressure F D-9

RAX System Pressure Q E-12

Rear Slack Adjuster Pressure I2 G-14

Rear, Left Parking Brake Release Press. J3 J-14

Rear, Right Parking Brake Release Press. J4 B-14

Right, Front Wheel, Brake Cooling Input Press. K3 E-2

Right, Front Wheel, Brake Cooling Output Press. K4 D-2

Right, Rear Wheel, Brake Cooling Input Press. K7 C-14

Right, Rear Wheel, Brake Cooling Output Press. K8 B-14

Right, Rear Wheel, Traction Pilot Pressure S2 H-7

Secondary Retract Accumulator Pressure H I-5

Service Brake Acummulator Pressure G I-4

SOS, Brake Actuation C I-6

SOS, Hoist and Brake Cooling B I-9

SOS, Strg, Fan, Drive A E-10

Steering Accumulator Pressure E E-3

Steering Pump Pressure D F-8

Supply Pump Pressure P3 C-9

FLUID POWER SYMBOLS

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

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

SOLENOIDor MANUAL

SOLENOIDand 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

ELECTRICAL SYMBOLSHydraulic Symbols (Electrical)

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)

T

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: 278-8439, CHANGE: 00, VERSION: -MEDIA NUMBER: KENR8398-04 THIS SCHEMATIC IS FOR THE 793F OFF-HIGHWAY TRUCK HYDRAULIC SYSTEM

A

B

C

D

E

F

1234567891011121314

G

H

I

J

1234567891011121314

A

B

C

D

E

F

G

H

I

J

LINE PATTERNS

Drain / Return Lines

Component Group

Air Line

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

HYDRAULIC CIRCUIT COLOR DESCRIPTIONSBRAKE RELEASE PUMP AND CIRCUIT

DRAIN / BRAKE COOLING

HOIST PUMP AND CIRCUITSTEERING CIRCUITSUPPLY LINEFAN PUMP AND CIRCUITBRAKE PUMP AND CIRCUITSUPPLY PUMP AND CIRCUITPARKING BRAKE CIRCUITREAR AXLE LUBE PUMP AND CIRCUITDRAIN / RETURN LINE

HIGH PRESS.RLF

LOW PRESS.RLF

DUAL STAGE SIGNAL SPOOL

SIGNALORIFICE #2

SIGNALORIFICE #1

ORIFICE

COUNTERBALANCEVALVE CARTRIDGE

ROD END VENTSLOT ACROSS

STEM

SOS

LEFT REAR

RIGHT REAR

LEFT FRONT

RIGHT FRONT

MAIN RELIEF DUMP SPOOL

AP

B

SW

M1U B

REAR AXLE BANJO HOUSING SUMPSEE POWERTRAIN SCHEMATIC

FINALDRIVE DIFFERENTIAL

HP

P

LS HT

T

EF

RL

CRCL

BRAKE SYSTEM, STEER AND FAN, HOIST AND BRAKE COOLING, MECHANICAL DRIVE: RM757 and RM952

M

TOFAN / STEERINGPUMP

B

I2

K6

J3

K8 J4

K7

K5

P2

H

FK4

K3

I1

K1

Q

P1

S1

S2

P3

D

K2

R

J2

J1

G

E

A

L2

L1

N M1 M2

C

AC

C2

BC

D

HO

IST

TCS

PS

2

AC

C1

PS

1

RA

X

T2

TANK

PB

PS5 R SUPPLY PS4 F

FSB

T1

TSB

PS3

P

T

A

SV3

FL1PR1

SQ1

RV1

LE1

SV2

OR1

CV1 CV2

PD1

0R5 0R6

HF1 SV1

0R2 0R9

0R3 0R7

PD2

SH1

HF2 PD3

PLUG1

HF3

SH2

0R4 0R8

(1) ACCUMULATOR GPBRAKE (ACC1)

291-1546 (2) ACCUMULATOR GPBRAKE (ACC2)

291-1546

(4) BREATHER157-7911

(7) CYLINDER GPTELESCOPING

HOIST295-5708

(8) FILTER OILBREATHER

4T-6788

(9) FILTERCASE DRAIN

290-2569

(10) FILTER GPFAN/ STEERRETURN339-9706

(11) FILTER GPOIL BRAKE

290-2567

(12) FILTER GPOIL HOIST / BRK

COOLING339-9702

(13) FITTING ORIFICE 1A.C. ONLY8X-7851

(16) MOTOR GPFAN

240-7790

(17) PUMP / MOTOR GPBRAKE RELEASE

5T-1060

(18) PUMP GPFAN / STEERING

291-7263

(19) PUMP GPHOIST / BRAKE

310-4846

(20) PUMP GPMETERING

(HMU)9T-1318

(21) SCREENPUMP BEARINGFLUSHING RET247-8298

(22) SCREEN GPHOIST LINES6E-5472

(23) SLACK ADJ GPFRONT

205-0560

(24) SLACK ADJ GPREAR

205-0560

(25) VALVE GPCHECK 1332-7350

(26) VALVE GPCHECK 26E-4701

(27) VALVE GPCHECK BRK REL

EL PUMP123-4750

(28) VALVE GPCHECKBRK REL123-4750

(29) VALVE GPCONTROL

HOIST / BRKCOOLING247-1437

(30) VALVE GPMAKEUP183-7170

(31) VALVE GPSOL/ MNFLD198-6577

(32) VALVE GPSOL / RLFSTR ACC272-9849

(33) VALVE GPSTEERING

9T-8931

(6) CONNECTORORIFICE311-6676

(34)CONTROL GPFOOT BRAKE315-5037

(35) CYLINDER GPSTEERING

9T-8912, 205-0560

(36) FILTER GPOIL, RAX333-6434

(37) MANIFOLD GPCONTROL RAX299-3258

(38) MOTOR GPBRAKE COOLING198-6041

(39) MOTOR GPRAX202-9940

(40) PUMP GPBRAKE COOLING

197-8885

(41) PUMP GPRAX214-1555

(42) SCREEN ASHYDR. OIL COOLER

149-2754(Extra Retarding Only)

(43) TANK GPHYDRAULIC

288-5701

(44) VALVE / MTG GPCONTROL BRAKES (STD WHL)285-5630(45) VALVE / MTG GPCONTROL BRAKES (XL WHL) NOT SHOWN283-9559

(46) VALVE GPRELIEF BRAKE

OIL COOLER6E-5855

(47) VALVE GPTRACTION CONTROL

222-4744

(3) ACCUMULATOR GPSTEERING308-2856

(48) ACCUMULATOR GP (PED)308-3556

(51) PLUG ASREAR AXLE CLR242-7114

(52) VALVE GPPRESS RDC. RAD.

FAN CNTRL226-0835

(53) CORE ASOIL COOLERBRAKE290-2729(Extra Retarding Only)

(54) CORE ASOIL COOLER

BRAKE336-9641

(55) CORE GPOIL COOLERSTEERING199-6683

(56) SENSOR GPPRESS. BRAKE

PUMP221-3405

(57) SENSOR GPPRESS. BRK (Acc1)

221-3405 (58) SENSOR GPPRESS. BRK (ACC2)221-3405

(59) SENSOR GPPRESS. DIFF. OIL221-3415

(60) SENSOR GPPRESS. RR BRK OIL, LH221-3410

(65) SENSOR GPPRESS. RR BRK OIL, RH

221-3410

(62) SENSOR GPPRESS. STEER ACC.

221-3405

(63) SENSOR GPPRESS. STEER ACC

221-3405

(64) SENSOR GPSPEED

COOLINGPUMP DRIVE

186-0131

(61) SENSOR GPSPEED, FAN

186-0131

(68) SWITCH ASPRESS. SERV. BRK

(REAR) A.C. ONLY128-5091

(67) SWITCH ASPRESS. SERV. BRK (FRNT)128-5091

(14) FITTINGORIFICE 28X-7851

(15) FITTINGORIFICE 3

8X-7851

(50) MOTOR GPRAX OIL CLR FAN

307-1504(49) COOLER GPRAX OIL CLR

320-8196

MECHANICALPUMP DRIVE

(6) CONNECTORORIFICE311-6676

(13) FITTINGORIFICE 1A.C. ONLY

8X-7851

T1 T2 R G2 Ma Mb B G1 R T2 T1

Qmin Qmax

M1 S M1

Qmax Qmin

A U2SL

L1U1

TOMECHANICAL DRIVE

RAISE HOLD SNUB FLOAT LOWERSpool sections by color =

BRAKE COOLING

B

K8

K7

K4

K3

K6

K5

K2

K1

64

54

5346

42

40

3812

BRAKE CONTROL

Left Side, Center of Chassis

G

H

P1 R58

57 5645 44

28

26

13 11

6

2

1

FAN CIRCUIT

Viewed From Front

F 65

55

30 16

10

HOIST CONTROL

Viewed from Rear and Above

L2

L1

29

22

7

7

HYDRAULIC OIL TANK

P2

43

25 9

8

4

PUMPS AND DRIVE

BrakePump

FanPump

SteeringPump

HoistPump

PumpDriveP3

M2 M1 N

19

18

RAX OIL COOLER

D

Q

63

59

51

50 49

4139 3736

31

SERVICE AND PARKING BRAKES

J4J3

I2

J2 J1

I1

34

2724

23

21

17

STEERING CONTROL

VIEW A-A

E

A 62

48

35

35

33 32

31

20

15

14

3

TRACTION CONTROL

Left Side, Center of Chassis, Inside of Frame

S2

S1

67

61

60

47