RENR9175-00
30 Page, TRM
©
2005 Caterpillar
All Rights Reserved
Printed in U.S.A.
RENR9175
April 2005
345C Material Handler
Hydraulic System
M2R1-UP
With Fixed Cab Riser
FRONT VIEW
Tap Locations
Pressure, Sampling, and Sensor
Tap
Number
Description
Schematic
Location
TP1 Pilot Pressure Test Port A-4
TP2 Work Tool Rotate Pressure Test Port (B2) E-3
TP3 Work Tool Rotate Pressure Test Port (B1) E-3
SOS Oil Sampling Port A-4
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 RESTRICTION
VARIABLE and PRESSURE
COMPENSATED
PRESSURE
COMPENSATION
PUMP: VARIABLE and
PRESSURE COMPENSATED
ENERGY TRIANGLES
HYDRAULIC PNEUMATIC
MEASUREMENT
PRESSURE
TEMPERATURE
FLOW
ROTATING SHAFTS
UNIDIRECTIONAL BIDIRECTIONAL
PUSH-PULL LEVER PEDALGENERAL MANUAL PUSH BUTTON SPRING
MANUAL CONTROL SYMBOLS
HYDRAULIC MOTORS
FIXED
DISPLACEMENT
VARIABLE DISPLACEMENT
NON-COMPENSATED
UNIDIRECTIONAL
BIDIRECTIONAL
HYDRAULIC PUMPS
FLUID STORAGE RESERVOIRS
CROSSING AND JOINING LINES
VALVE ENVELOPES
VALVE PORTS
BASIC COMPONENT SYMBOLS
FLUID CONDITIONER
PUMP or MOTOR
FLUID POWER SYMBOLS
FIXED
DISPLACEMENT
VARIABLE DISPLACEMENT
NON-COMPENSATED
UNIDIRECTIONAL
BIDIRECTIONAL
VALVES
PILOT CONTROL SYMBOLS
RELEASED PRESSURE
EXTERNAL RETURN
INTERNAL RETURN
REMOTE SUPPLY PRESSURE
SIMPLIFIED
COMPLETE
INTERNAL
SUPPLY PRESSURE
ACCUMULATORS
SPRING LOADED
GAS CHARGED
SOLENOID
or MANUAL
SOLENOID
and PILOT
SOLENOID and
PILOT or MANUAL
COMBINATION CONTROLS
SOLENOID
SERVO
THERMAL
DETENT
HYDRAULIC AND PNEUMATIC CYLINDERS
DOUBLE ACTING
SINGLE ACTING
BASIC
SYMBOL
SPRING
LOADED
CHECK VALVES
TWO
POSITION
INFINITE
POSITIONING
FLOW IN ONE
DIRECTION
FLOW ALLOWED IN
EITHER DIRECTION
THREE
POSITION
CROSS
FLOW
PARALLEL
FLOW
INTERNAL PASSAGEWAYS
NORMAL POSITION
AB
PT
AB
PT
SHIFTED POSITION
INFINITE POSITION
CONTROL VALVES
ATTACHMENT
MANUAL SHUTOFF
SHUTTLE PILOT
CONTROLLED
Hydraulic Symbols (Electrical)
Electrical Symbols Table
325-AG135 PK-14
Circuit Identification
Number
Wire Color
Wire Gauge
Harness identification code
This example indicates
wire135inharness"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 Color
Circuit Number
Identification
B
A
Wire
Wire
(EXAMPLE VALVE)
Current Standard
Transducer
(Fluid)
Transducer
(Gas / Air)
G
Generator
Electrical Wire
Pressure Switch
M
Electric Motor
Pressure Switch
(Adjustable)
Temperature Switch
T
Pressure
Symbol
Temperature
Symbol
Level
Symbol
Flow
Symbol
Electrical Symbols (Electrical)
Description
Part
Number
Machine
Location
Schematic
Location
Accumulator Gp - Pilot Manifold 164-6981 B-5 F-26 , R-26
Cooler Gp - Oil 210-8164 B-7 F-28 , W-28
Cylinder Gp - Boom Note A F-4 G-17,S-17,U-17
Cylinder Gp - Grapple Note A E-1 A-16 , T-16
Cylinder Gp - Stick Note A B-8 I-5 , S-5 , U-5
Filter Gp - Return (Inside Hydraulic Tank) 173-3434 A-5 and A-6 F-24 , Q-24
Filter Gp - Drain Return 126-2075 A-3 and A-5 F-26 , R-26
Filter Gp - Hydraulic Generator 126-2075 B-1 F-20 , Q-20
Filter Gp - Pilot Pressure 188-2084 A-4 F-26 , R-26
Generator Gp - Hydraulic 255-4408 B-1 F-20 , Q-20
Motor Gp - Cooling Fan 242-6904 A-6 F-28 , W-28
Motor Gp - Left Swing 225-4506 F-8 E-24 , T-24
Motor Gp - Left Travel 170-7572 F-6 B-28 , Y-28
Motor Gp - Right Swing 225-4506 F-7 E-24 , T-24
Motor Gp - Right Travel 170-7572 F-4 B-28 , P-28
Pump Gp - Drive / Idler / Pilot 259-0818 A-3 F-28 , S-28
Sensor Gp - Drive Pump Pressure 221-8869 B-2 F-28 , S-28
Sensor Gp - Idler Pump Pressure 221-8869 A-2 F-28 , S-28
Switch As - Implement Pressure 106-1079 D-4 G-25 , U-25
Switch As - Travel Pressure 106-1079 D-4 G-25 , U-25
Swivel Gp - Joint 225-4547 E-6 D-22 , T-22
Tank Gp - Hydraulic 227-0431 A-6 F-24 , Q-24
Valve Gp - Boom / Swing Priority 232-4102 B-4 E-25 , U-25
Valve Gp - Stick Check & Relief 202-9264 A-8 and B-8 J-8 , S-8 , U-8
Valve Gp - Boom Load Control 157-2283 E-4 G-22 , T-22
Valve Gp - Boom Load Control 156-0844 F-3 and F-4 H-16,S-17,U-13
Valve Gp - Check Cooler Bypass 123-2505 B-7 G-26 , X-26
Valve Gp - Check Slow Return 185-0384 B-7 G-26 , X-26
Valve Gp - Left Swing Cushion 116-3420 E-8 E-24 , T-24
Valve Gp - Left Travel / Counterballance 165-9338 E-6 B-28 , Y-28
Valve Gp - Lock Solenoid 121-1491 B-5 F-26 , R-26
Valve Gp - Main Control 239-8852 D-1 thru D-6 G-25 , U-25
Valve Gp - Pilot Control Grapple / Boom 206-3305 C-7 J-20 , V-20
Valve Gp - Pilot Control Manifold 215-5037 B-6 F-26 , R-26
Valve Gp - Pilot Control Stick / Swing 206-3305 C-8 J-20 , X-20
Valve Gp - Pilot Control Travel 165-9522 D-8 I-19 , W-19
Valve Gp - Power Shift Control 225-4518 B-2 F-28 , S-28
Valve Gp - Reversing Fan Control 234-4624 A-7 F-28 , W-28
Valve Gp - Reversing Fan Relief 247-8954 A-7 F-26 , V-26
Component Locations
Valve Gp - Reversing Fan Solenoid 242-6880 A-6 G-26 , U-26
Valve Gp - Right Travel / Counterballance 165-9338 E-5 B-28 , P-28
Valve Gp - Swing Brake Solenoid 121-1491 B-6 F-26 , R-26
Valve Gp - Travel Speed Solenoid 121-1491 B-6 F-26 , R-26
Valve Gp - Work Tool Rotate 232-4103 F-2 G-25 , T-25
Valve Gp - Work Tool Rotate Solenoid 190-7820 E-3 E-29 , Q-29
Note A: See the Parts manual for specific cylinder part number.
DR2 T-OUT2
DR1
PSA1
PSA2
P-IN
Pi 1
P2
PAC
DR6
DR5
DR4 DR3
Pi 2
T-OUT1
Machine Component Locations
Main Control Valve
Pilot Manifold Control Valve
LOCK SWING TRAVEL
WORK TOOL ROTATE
FILTER GROUP
TP1
TP2
TP3
SOS
Pilot Filter
Work Tool Rotate Valve
aL5 aL4 bL3 aL2 bL1 bR1 bR2 aR3 aR4
AL4
BL3 BL2 BL1
BL4 AL3 AL2 AL1
BR1 BR2
AR3
AR4
AR1 AR2 BR3
PTA PSW
Y
X
TRAVEL
(L)
STR
TRAVEL
SWING
PiH
STICK
(1)
BOOM
(2)
BOOM
(1)
ATT
GRAPPLE
TRAVEL
(R)
STICK
(2)
RENR9175-00
30 Page, Color 2, TRM
DRAIN / RETURN LINE
LINES GROUP COLOR DESCRIPTIONS
DRIVE PUMP OUTPUT
IDLER PUMP OUTPUT
POWER SHIFT CONTROL CIRCUIT
PILOT PUMP OUTPUT
HYDRAULIC OIL COOLING PUMP OUTPUT
GRAPPLE CYLINDER CONTROL CIRCUIT
SUPPLY LINE
BUCKET CONTROL & BUCKET CYLINDER CIRCUIT
RIGHT TRAVEL CONTROL & RIGHT TRAVEL MOTOR CIRCUIT
TRAVEL SPEED CONTROL CIRCUIT
STICK CONTROL & STICK CYLINDER CIRCUIT
BOOM CONTROL & BOOM CYLINDER CIRCUIT
GENERATOR PUMP OUTPUT
LEFT TRAVEL CONTROL & LEFT TRAVEL MOTOR CIRCUIT
SWING CONTROL & SWING MOTOR CIRCUIT
SWING BRAKE CONTROL CIRCUIT
WORK TOOL ROTATE PUMP
WORK TOOL ROTATE CONTROL CIRCUIT
LINE PATTERNS
Drain / Return Lines
Component Group
Pilot / Load Sensing Pressure
Pressure Line
Attachment
Air Line
CALLOUTS
Taps (Pressure, Sampling,Sensor) by letter
TP1
1
2
3
4
5
6
7
8
A
C
D
E
F
1
23
4
56
7
8
A
B
C
D
E
F
B
TRAVEL MOTOR (LEFT) TRAVEL MOTOR (RIGHT)
SWING MOTOR
SWING MOTOR
BOOM(1)
STICK(2)
GRAPPLE
TRAVEL(R)
TRAVEL(L)
SWINGSTICK(1)BOOM(2)
TRAVEL(R)TRAVEL(L)
HL
aL5
Dr
R2
X
Pp1
R1
Y
HR
AR4
R3
Pi1P2 P-IN PSA2 DR1
T-OUT2 DR2
DR3
DR4
Pi2 DR5
DR6
T-OUT1
P1 P2
T
B1 A1 B2 A2
A4 B1 Dr1 Di PS2 PB
Pi2
D0 PS1
Pi1
P1
PG2
PB2
DE2 B2A2
PA2
M2
DB2
PG1
PB1
DE1
B1A1
PA1
M1
DB1
BA
X
BA
B
A
MA MAMB MB
L' L'
T2 T2
T1 T1
BR BR
dL5
(DOWN)
AL4
(UP)
AL2BL2
PAT
SWIVEL
(F)(B)
PTAPSW
(BACK)
(FWD)
dST1
(BACK)(F)(B)(R)
(FWD)(L)
(R) (L)
dSW
PiL
(OUT)
(IN)
BR3
(UP)
APi2 dR5
PSA1
X
(IN,OUT)
Pp2
PCPG
T
OUT IN
TP TT
BACK FWD FWD
T5 T2T1 T3 T6 T4
BACK
PiH
PT
A
B
M
LS
aR4
PB
PA
-μ
-μ -μ
-μ
AR2 BR2
AR1BR1 AL1 BL1
bR1 aR1 aL1 bL1
AR3
BR3
aR3
BR2
AR2
bR2
BR1
AR1
bR1
bL1
BL1
AL1 bL3
BL4
AL4
bR3
aR2 aR1
PR
PL aL1 aL3
bL4
T
P
A1
B1
A2B2
aL2
bL2
dR4
aL4
NO.1(TRAVEL)
NO.2(SWING)
NO.3
(LOCK)
SWINGSTICK BOOMGRAPPLE
OUT IN R L OPEN CLOSE DOWN UP
JLP JLT
JL1 JL3 JL2 JL4 JR4 JR2 JR3 JR1
JRP JRT
A1
B1
A2
B2
A3
B3
A4
B4
A5
B5
A6
B6
A7
B7
A8
B8
aR3bR2 aR2aL2bL2 bL4aL4
Pp
Dr
T
A
C
C
A
T
Dr
Pp
aR3
bR3
STICK CYLINDERS
XX
Dr1
X2
X1
Dr2
A
B
Pi
C
Dr
T
A
Dr
A
X
Pi
Pi
Dr
C
C
X
Bd1
Bd2
OWD
BOOM CYLINDERS
X
AR3
BR3
bL4
BL4
VALVE GP
WORK TOOL ROTATE
SOLENOIDS
190-7820
(CLOSE)
(OPEN)
SHV
GRAPPLE
MULTIPLE CYLINDERS
BL2
AL2
)(
AL4
AL2
BL2
GENERATOR
OR
HOT LOOP
DR
DR1
L3
L2
A
A
B
B
T
P
S
S
TPi
A1
a1
PL
a5
a3
PSV
a4
PR
A2
a2
A2
BL4
8
1
7
6
5
2
3
AR3
THIS SCHEMATIC IS FOR THE 345C MH
FIXED CAB RISER
Part #: 253-0313 CH 01
Components are shown installed on a fully operable machine with the k ey and engine
off and transmission shifter in neutral.
SENSOR GP
PUMP DRIVE
PRESSURE
221-8869
SENSOR GP
PUMP DRIVEN
PRESSURE
221-8869
VALVE GP
WORK TOOL ROTATE
232-4103
VALVE GP
BOOM LOAD
CONTROL
156-0844
VALVE GP
BOOM LOAD
CONTROL
156-0844
VALVE GP
BOOM LOAD
CONTROL
157-2283
MOTOR GP
RT TRAVEL
170-7572
VALVE GP
RT TRAVEL
COUMTERBALLANCE
165-9338
MOTOR GP
LT TRAVEL
170-7572
VALVE GP
LT TRAVEL
COUMTERBALLANCE
165-9338
VALVE GP
LEFT SWING
CUSHION
116-3420
MOTOR GP
LT SWING
225-4506
MOTOR GP
RT SWING
225-4506
VALVE GP
PILOT CONTROL
TRAVEL
165-9522
VALVE GP
PILOT CONTROL
STICK/SWING
206-3305
VALVE GP
PILOT CONTROL
GRAPPLE/BOOM
206-3305
VALVE GP
MAIN CONTROL
239-8852
MOTOR GP
COOLING FAN
242-6904
VALVE GP
REVERSING
FAN RELIEF
247-8954
VALVE GP
REVERSING
FAN CONTROL
234-4624
VALVE GP
STICK CHECK
& RELIEF
202-9264
VALVE GP
CHECK COOLER
BYPASS
123-2505
VALVE GP
CHECK
SLOW RETURN
185-0384
VALVE GP
STICK CHECK
& RELIEF
202-9264
VALVE GP
REVERSING FAN
SOLENOID
242-6880
TANK GP
HYDRAULIC
227-0431
FILTER GP
RETURN
173-3434
ACCUMULATOR GP
PILOT MANIFOLD
164-6981
VALVE GP
TRAVEL SPEED
SOLENOID
121-1491
VALVE GP
SWING
SOLENOID
121-1491
VALVE GP
LOCK
SOLENOID
121-1491
VALVE GP
PILOT CONTROL
MANIFOLD
215-5037
VALVE GP
BOOM/SWING
PRIORITY
232-4102
FILTER GP
DRAIN
RETURN
126-2075
FILTER GP
DRAIN
RETURN
126-2075
FILTER GP
PILOT PRESSURE
188-2084
PUMP GP
GENERATOR
263-8582
GENERATOR GP
HYDRAULICS
255-4408
FILTER GP
HYDRAULIC
GENERATOR
126-2075
VALVE GP
POWER SHIFT
CONTROL
225-4518
PUMP GP
DRIVE/IDLE
& PILOT
259-0818
TP1 SOS
TP2 TP3
SWITCH AS.
TRAVEL PRESS
106-0179
SWITCH AS.
IMPLEMENT
PRESSURE
106-0179
SWIVEL GP
JOINT
225-4547
COOLER GP
OIL
210-8164
