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SENR4778-02

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ONEPOSITION TWO POSITION THREEPOSITION

V EN TE D P RE SS UR IZ ED RETURNABOVEFLUIDLEVEL RETURNBELOWFLUID LEVEL

LINESCROSSING LINESJOINING

TWO-WAY THREE-WAY FOUR-WAY

SPRING CONTROLVALVES RESTRICTION LINERESTRICTION

(FIXED)

2-SECTIONPUMP

MAIN AUX.

SPRING

(ADJUSTABLE)

VARIABILITY LINERESTRICTION

(VARIABLE)

LINERESTRICTIONVARIABLEand PRESSURE

COMPENSATED

PRESSURE

COMPENSATION

PUMP: VARIABLEan dPRESSURECOMPEN SATED

ENERGYTRIAN GLES

HYDRAULIC PNEUMATIC

MEASUREMENT

PRESSURE TEMPERATURE FLOW

ROTATING SHAFTS

U NI DI RECT ION AL BI DI REC TI ONAL

PUSH-PULL LEVER PEDALGENERAL MANUAL P USH BUTTON SPRING

MANUAL CONTROL SYMBOLS

HYDRAULIC MOTORS

FIXED

DISPLACEMENT

VARIABLEDISPLACEMENT

NON-COMPENSATED

UNIDIRECTIONAL

BIDIRECTIONAL

HYDRAULIC PUMPS

FLUID STORAGE RESERVOIRS

CROSSING AND JOINING LINES

VALVE ENVELOPES VALVE PORTS

BASIC COMPONENT SYMBOLS

FLUIDCONDITIONERPUMPor MOTOR

FLUID POWER SYMBOLS

FIXED

DISPLACEMENT

VARIABLEDISPLACEMENT

NON-COMPENSATED

UNIDIRECTIONAL

BIDIRECTIONAL

VALVES

PILOT CONTROL SYMBOLS

RELEASED PRESSURE

EXTERNALRETURN INTERNALRETURN

REMOTE SUPPLYPRESSUR E

SIMPLIFIED COMPLETE INTERNAL

SUPPLYPRESSURE

ACCUMULATORS

SPRING LOADED GASCHARGED

SOLENOIDor MANUAL

SOLENOIDand PILOT

SOLENOIDandPILOTor MANUAL

COMBINATION CONTROLS

SOLENOID S ERV O TH ER MA L D ET EN T

HYDRAULIC AND PNEUMATIC CYLINDERS

DOUBLEACTINGSINGLEACTING

BASIC

SYMBOL

SPRINGLOADED

CHECK VALVES

TWO

POSITION

INFINITE

POSITIONING

FLOWINONEDIRECTION

FLOWALLOWEDINEITHERDIRECTION

THREE

POSITION

CROSSFLOW

PARALLELFLOW

INTERNAL PASSAGEWAYS

NORMALPOSITION

A B

P T

A B

P T

SHIFTEDPOSITION INFINITEPOSITION

CONTROL VALVES

ATTACHMENT

MANUALSHUTOFF

S HU TT LE P IL OTCONTROLLED

SENR4778-02

October 1993

966F & 966F Series II Wheel Loaders

Hydraulic System

1SL1-UP

3XJ1-UP

4YG1-UP

8BG1-UP

9YJ1-UP

1993 Caterpillar

All Rights Reserved

Printed in U.S.A.

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SENR4

778-02

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THIS SCHEMATIC IS FOR THE 966F AND 966F SERIES II WHEEL LOADERS

Components are shown installed on a fully operable machine with the key and engine off and transmission

shifter in neutral.

Refer to the appropriate Service Manual for Troubleshooting, Specifications and Systems Operations