Case 120 User manual

120
Crawler
Service Manual
S406208M2

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TABLE OF CONTENTS
GENERAL
SafetyPrecautions ............................................................................. 3,4
Introduction
..................................................................................... 5
Nomenclatureand MachineGeneral Description
................................................. 6,7
Directional Reference
............................................................................ 8
Partsand Service
................................................................................ 8
SECTION 1 • SCHEDULED PREVENTIVE MAINTENANCE
Lubricantand Fluid Recommendations ............................................................ 9
ComponentCapacities
.......................................................................... 10
PressureSettings
............................................................................... 10
MaintenanceSchedule
.......................................................................... 11
Service Chart ................................................................................ 12, 13
Pictorial Listing
of Grease Fitting Locations ................................................... 14, 15
SECTION 2• THE UNDERCARRIAGE
Description, Maintenanceand Troubleshooting ............................................ 16 thru 26
Carbodyand Turntable Bearing ................................................................ 17
Track Assemblies
...................................................................... 18 thru 22
Track Drive Assemblies ................................................................ 22 thru 26
Disassemblyand Repair .................................................................. 27 thru 42
General Cleaning Instructions ................................................................. 27
UpperTrack Rollers
........................................................................ 28,29
LowerTrack Rollers
........................................................................ 30,31
IdlerWheel Assembly .................................................................. 31 thru 33
Digging
Brake ............................................................................ 34-35B
Track DriveTransmission
.............................................................. 36 thru 42
SECTION 3• THE UPPERSTRUCTURE
Description, Maintenanceand Troubleshooting ............................................ 43 thru 54
Pump Drive System
.................................................................... 43 thru 48
Swing System
......................................................................... 49 thru 53
Boom
Assembly. . ... . .. .. . .. .. ... .. . .. ... .. . .. ... .. . ... .. .. ... . .. .. . .. . .. .. . ... . . . .......... 54
Disassemblyand Repair . ................................................................. 55 thru 67
Pump Drive Transmission and Clutch
................................................... 56 thru 59
House
Brakes ................................................................................ 59
Swing Gearbox ........................................................................ 59 thru 65
Turntable Bearing Replacement
........................................................ 65 thru 67
Boom Removal
..........................................................•.................... 67
SECTION 4• THE ELECTRICAL SYSTEM
Description, MaintenanceandTroubleshooting ............•..•.•.............••....•.....• 68 thru 79
The Charging System .................................................................. 69thru 74
Control Circuits .•........•..............................................•...•...•..•.. 74 thru 77
Lightsand Instrument Circuits .........................................•...................... 78
Disassembly and Repair . ........................................................................ 79
1
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CONTENTS
MODEL 12 0 CRAWLER
SECTION 5• THE HYDRAULIC SYSTEM
Description, Maintenanceand Troubleshooting ........................................... 80 thru 127
Introduction
to Hydraulics .................................................................... 80
General Descriptionand System Maintenance
........................................... 81 thru 89
Hydraulic Reservoirand Supercharge System
........................................... 82 thru 86
HydraulicSystem Flushing and Troubleshooting
........................................ 87 thru 89
Main HydraulicSystem
............................................................... 90 thru 100
Pilot Control System ................................................................. 101 thru 107
AuxiliarySystem
........................................................................ 107,108
Track Drive Circuit
................................................................... 108 thru 114
Tool CylinderCircuit.
........................................................................ 115
Swing Circuit.
...................................................................... 116 thru 118
Crowd Cylinder Circuit.
.................................................................. 119,120
Hoist CylinderCircuit (includes Fast Hoist Circuit) .................................... 120 thru 124
Pump Drive Clutch Circuit.
................................................................... 125
CounterweightSystem
................................................................... 126,127
Disassemblyand Repair
................................................................ 128thru 173
Hydraulic Reservoir
...................................................................... 128,129
Main Pumps
........................................................................ 129thru 137
Main Control Valves
................................................................. 138 thru 140
PowerSensing Valve
........................................................................ 141
Hydraulic Filters(In-line) ..................................................................... 142
Charging Pump
...................................................................... 143 thru 145
ModulatorValves
.................................................................... 146thru 150
Swing Cushion Valve
........................................................................ 151
Swing Motors ....................................................................... 152 thru 156
Tool, Crowd and
Hoist Cylinders ...................................................... 157thru 161
Fast Hoist Control Valve ..................................................................... 161
Track Drive Motors .. :. .............................................................. 162 thru 165
Hydraulic Swivel.
........................................................................ 166, 1-67
CounterweightControl Valve ............................................................. 168,169
CounterweightCylinders
............................................................ 170 thru 172
Clutch Cylinder
.............................................................................. 173
TORQUE CHARTS AND SCHEMATICS . ...................................................... 174 thru 179
2
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MODEL 12 D CRAWLER
SAFETY PRECAUTIONS
THIS
SAFETY ALERT SYMBOL IND/CA TES
A
IMPORTANT
SAFETY MESSAGES
IN THIS
MANUAL WHEN YOU
SEE
THIS SYMBOL,
CAREFULLY READ THE
MESSAGE
THAT
FOL-
LOWS AND
BE ALERT
TO THE
POSSIBILITY
OF PERSONAL INJURY OR DEA TH.
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CAUTION [NCilfJE FAr\J Af'JD REL TS
T() 1irI•v,·rIt [Hl'.,
1
,1I ,J,-, Sf"fll •us lflJLHY J\ "'' I
C0lild( 1 .vrtli IUld1II1/I fdrl ,Hlii hf-'lts
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1
11•1 i1II1
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r ,11111"1,. JII' 111 rH:UTRAL
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~ l1,111ily IIHI ~ IIU'.V l1i1W tr, LI'.<' tlir•1r1
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A
WARNlf'JC Thrc; macl1111c ,,, r•qu,
th,124vultelectr1 stvnI Spdrk111q
wrll occur dt· qI1•c11(1r clrst,-111ces tlrdtl
wrtlr a co11v1_'11t1011dl 12 vult tern
r1 JEVER \NEAR Rlr\JCS OR OfHf,R
MET.AL OBJE'CTS th,n III.iv qr,11111<I
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3
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SAFETY PRECAUTIONS
A
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1
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\\ARNl1\Jli 81•fure c1tte11111t111q to
cl1s<JssP111bll' tlw sh()( k Jhsor her ''\ l111cler
rnc1I, slllP dll 1ircssur,· rs relre",l'ci frrst
4
A \\11pP
rnl sprlls rmniedratPly ,rnd kePp
work dlPd dS clP,111 ,1s possrhlE A
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MODEL 12 D CRAWLER
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l<-',1(1 trr st
A
CAUTION WIH'ri I lw1 krrHt 1 ""I 1111 IPu•I
remove 1,Fl1c1tr1r \,ii) r,l1Ji:,ly Ir) fr llt'\f'
pressur1° ,v1tli111 th,• syst1·111
A
When bleecl111g brakes, loosen hleecler
plug approxrrnatelv orilv crne half to
three quarter turn or u1111I orl 1ust stc1rts
to flow If pluq rs loosened too far rt
may he hlowri out urider pressure
WAR~~li'r~G Us,· extr1·r1w , ,11e vvlwn
A hdrHll111q thr· tld[k NP\Pr 1r1•,P11 f1r1qers
~ ln·twe,•11 tr dCK ,;l1oes •vh,·n r ernrl\ 1r1g the
trcid
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INTRODUCTION
This manual is designed to serve as a guide in maintaining and servicing the
120 CRAWLER. All components and systems are covered, with the
exception
of the engine which is covered in the engine manufacturer's
manual.
The book
is basically divided into five sections, preceded by a general section
on safety. nomenclature and Parts & Service information.
Section 1
gives the Scheduled Preventive Maintenance needed to keep the
machine
in top operating condition. It includes a maintenance schedule,
component capacities, service chart, lubricant and fluid recommendations,
and a pictorial listing
of all grease fitting locations. If more detailed
maintenance information
is required, it can be found in the individual service
sections.
Section 2 covers
the undercarriage. It includes the turntable bearing, the
tracks and
the track drives.
Section 3 covers
the mechanical components of the upperstructure. Included
are
the engine, pump drive transmission, the swing assemblies and the boom
assembly.
Section 4 covers
the Electrical System. It is divided into the charging system,
lights and instrumentcircuits, and
the control circuits.
Section 5 covers
the Hydraulic System. It includes the main system, the pilot
control system,
the counterweight system, the supercharge system, and the
auxiliary hydraulic system.
The sections are divided into two subdivisions. The first part covers
description, maintenance and troubleshooting. The second part covers
disassembly and repair.
Torque Charts and Schematics
of the hydraulic and electrical systems are
located
in back of this manual. These should be used as aids in
troubleshooting.
5
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NOMENCLATURE
M0D ■ L 12 0 CRAWLER
6
NOMENCLATURE
TOOL CYLINDER r DIPPERSTICK
f ,,,..,,./ .. _ [ CROWD CYLINDER
, ......... "-
LOCATION OF
FUEL TANK
AND SWING
MOTORS
LOCATION OF TURNTABLE
BEARING
MAIN BOOM
LOCATION OF
HOIST CYLINDERS
ENGINE COMPARTMENT
WITH PUMPS, VALVES,
HYDRAULIC RESERVOIR
AND BATTERIES
LOCATION OF TRACK
IDLER WHEEL ASSEMBLY
LOCATION OF TRACK
DRIVE MOTORS, DIGGING LOCATION OF
BRAKES AND TRACK DRIVE--'
TRANSMISSIONS
MODULATOR CONTROLS
(Shown in DIGGING position with Track Drives to the Front)
Figure 1. Nomendature
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_,
MODEL 12 0 CRAWLER GENERAL
GENERAL DESCRIPTION
General Description
The 120 is a fully hydraulic unit. Power for operation
is supplied by a Detroit Diesel 12V-71 engine. Engine
power
is converted to hydraulic energy by two main
pumps and a two-section pump located at the rear
of
the engine.
Hydraulic systems include:
1) the Main System, 2)
the Pilot System, 3) the Counterweight system, and
4) the
Auxiliary System.
1) The Main System powers the work functions
(track drive, swing, hoist, crowd and
tool). Its
pumps
are driven off the engine through a
transmission and clutch which
can be either
manually
or hydraulically disengaged from the
engine. The
two main pumps supply oil to two
main control valve banks where it is available to
operate the individual work functions.
LEFT TRACK TOOL
SWING
2) The Pilot System supplies oil to the Modulator
Controls. The Modulator controls replace the
conventional mechanical linkage
to the main
valves and provide precise hydraulic control of
the main valve spools. The pilot system also
supplies oil
for release of the digging and house
brakes,
for release of the hoist and crowd anti-
drift valves, and for clutch engagement or dis-
engagement.
3) The Counterweight System allows the 14
ton
counterweight to be easily removed or installed.
4) The
Auxiliary System is connected directly into
the pilot system. Its pump is driven by an
electric motor, independent of the engine, and
can be used in case of engine failure to
pressurize the pilot system.
Figure 2 shows the power distribution
from the
engine
to the various machine functions.
MAIN
CONTROL
VALVE PUMP
BANK
MAIN
CONTROL PUMP
VALVE
:G
I
BANK
__ .,
CROWD
DRIVE MOTOR
CYLINDER MOTORS CYLINDER
CWT.
BRAKE
GEAR BOX
&
SPROCKET
BRAKE
GEARBOX
&
SPROCKET
PLANETARY
DRIVE
GEARBOXES
CLUTCH
CYLINDER
Figure 2. Block Diagram
MODULATOR
CONTROL VALVES
HOUSE BRAKE
CONTROL VALVE
DIGGING BRAKE
CONTROL VALVE
CLUTCH"CYL.
SOL. VALVES
CONTROL
VALVE
CWT.
CYLINDERS
CIRCUIT
AUXILIARY
i-----1 PUMP
(l).C. MOTOR)
7
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DIRECTIONAL
REFERENCE
F
R
0
N
T
DIRECTION
OF
TRAVEL
R
E
A
R
TRACK
DRIVES
Figure 3.
Direc.-tional
Reference
The turntable on the
DROTT
120
CRAWLER
will
rotate through a complete 360
degrees.
The normal
driving position
is
with
the Boom over the
front
of
the undercarriage (track drive transmissions
to
the
rear),
as
shown in figure
2.
In
th
is
position,
directional callouts
for
both
the turntable and the
undercarriage
are
the
same.
All
references
to
Front,
Rear, Right and
Left
will
be
made
with
respect
to
this
position.
RIGHT
is
the Operator's right;
LEFT
is
the
Operator's left.
PARTS
AND
SERVICE
When
writing
or calling the dealer or manufacturer
about
your
DROTT
machine, always refer
to
the
model and serial number,
as
well
as
the part name and
location. The machine identification plate
is
located
at lower right corner
of
the Operator's
Cab.
Figure 4. Machine Identification
INTERNATIONAL
SYMBOLS
The International Symbols shown here are
used
in
the
Service Chart
to
help
identify
areas
and
components which require periodic maintenance.
C!J
©
~
HYDRAULIC
RESERVOIR TRANSMISSION
GEAR BOX
8
Engine identification
is
found on the
Option
Plate
located on the engine valve cover. Major components
such
as
the pumps, motors, etc.
are
equipped
with
a
serial plate located on the component housing.
OPTION PLATE
Figure
5.
Engine
Identification
~
♦
_.......__.
cJ
•
...
LUBRICATE with
FILTER, AIR FILTER Multipurpose Grease
© s
Ii)
ENGINE OIL
COOLANT
DIESEL FUEL
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