INTERACTIVE SCHEMATIC
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X
EC-C3
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E-C61
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Hydraulic System
345C Excavator
©
2009 Caterpillar, All Rights Reserved
Printed in U.S.A.
RENR7356-02
January 2009
KBA1-UP
TBA1-UP
MDC1-UP
WDE1-UP
GBH1-UP
RFN1-UP
DHP1-UP
GJR1-UP
JAR1-UP
PJW1-UP
CPX1-UP
BWY1-UP
Without Heavy Lift and Fine Swing
COMPONENT LOCATION
Description
Part
Number
Machine
Location
Schematic
Location
Accumulator Gp - Pilot Manifold 164-6981 B-5
1
Cylinder Gp - Boom Note A E-2 2
Cylinder Gp - Bucket Note A E-3 3
Cylinder Gp - Stick Note A E-8 4
Filter Gp - Return (Inside Hydraulic Tank) 173-3434
A-5, A-6
5
Filter Gp - Drain Return
126-2075
6
Filter Gp - Pilot 158-8987
A-4
7
Motor Gp - Cooling Fan 242-6904
A-7
8
Motor Gp - Left Swing
225-4506
F-7
9
Motor Gp - Left Travel 232-6180
F-5
10
Motor Gp - Right Swing 225-4506
F-6
11
Motor Gp - Right Travel 232-6180
F-4
12
Pump Gp - Cooling 259-0814
B-2
13
Pump Gp - Drive / Idler / Pilot 259-0818
B-3
14
Sensor Gp - Drive Pump Pressure 221-8869
B-2
15
Sensor Gp - Idler Pump Pressure 221-8869
A-2
16
Switch As - Implement Pressure 106-0179
D-4
17
Switch As - Travel Pressure 106-0179
D-4
18
Swivel Gp - Joint 225-4547
E-5
19
Tank Gp - Hydraulic 227-0431
A-6
20
Valve Gp - Boom / Swing Priority 232-4102
B-4
21
Valve Gp - Boom Drift Reduction 153-5233
D-2
22
Valve Gp - Check Boom / Stick 2 239-8902
D-2
23
Valve Gp - Check Boom 2 239-8906
D-6
23
Valve Gp - Check Cooler Bypass 123-2505
B-7
24
Valve Gp - Check Slow Return 185-0384
B-8
25
Valve Gp - Check Stick 239-8904
D-5
23
Valve Gp - Left Swing Motor 116-3420
E-7
9
Valve Gp - Left Travel / Brake 165-9338
E-5
26
Valve Gp - Lock Solenoid 121-1491
B-5
27
Valve Gp - Main Control 230-2760
D-2
23
Valve Gp - Pilot Control Bucket / Boom 232-4158
C-7
28
Valve Gp - Pilot Control Stick / Swing 232-4157
C-8
29
Valve Gp - Pilot Control Travel 165-9522
D-8
30
Valve Gp - Pilot Manifold 215-5037
B-6
31
Valve Gp - Power Shift Control 225-4518
B-2
14
Valve Gp - Right Travel / Brake 165-9338
F-4
32
Valve Gp - Stick Drift Reduction 153-5233
D-5
33
Valve Gp - Swing Brake Solenoid 121-1491
B-6
34
Valve Gp - Travel Speed Solenoid 121-1491
B-6
35
Note A: See the Parts manual for specific cylinder part number.
A-5, A-6
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 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
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 ACTINGSINGLE 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
A B
P T
A B
P T
SHIFTED POSITION
INFINITE POSITION
CONTROL VALVES
ATTACHMENT
MANUAL SHUTOFF
SHUTTLE PILOT
CONTROLLED
ELECTRICAL SYMBOLS
Hydraulic Symbols (Electrical)
325-AG135 PK-14
Circuit Identification
Number
Wire Color
Wire Gauge
Harness identification code
This example indicates
wire 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 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
Pressure
Symbol
Temperature
Symbol
Level
Symbol
Flow
Symbol
Electrical Symbols (Electrical)
T
LINE PATTERNS
Drain / Return Lines
Component Group
Pilot / Load Sensing Pressure
Pressure Line
Attachment
Air Line
CALLOUTS
Taps (Pressure, Sampling, Sensor - by letter)
YY
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
ATTACHMENT 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
HEAVY LIFT CONTROL CIRCUIT
LEFT TRAVEL CONTROL & LEFT TRAVEL MOTOR CIRCUIT
SWING CONTROL & SWING MOTOR CIRCUIT
SWING BRAKE CONTROL CIRCUIT
THIS SCHEMATIC IS FOR THE 345C EXCAVATOR
MEDIA NUMBER: RENR7356-02
PART NUMBER: 230-2696, CHANGE: 05, VERSION: HE
Components are shown installed on a fully operable machine.
Refer to the appropriate Service Manual for Troubleshooting, Specifications.
12345678
A
B
C
D
E
F
12345678
A
B
C
D
E
F
(4) CYLINDER GP
STICK
SWING MOTOR
DB1
M1
PA1
A
B
PG1
SWING MOTOR
DB2
M2
PA2
A1
B1
DE1
PB1
PG2
PB2
A2
B2
DE2
TRAVEL(L) TRAVEL(R)
(19) SWIVEL GP
JOINT
225-4547
TRAVEL MOTOR (LEFT)
X
AG
BR
T1
T2
L
BR
T1
T2
L
A B
BG
BG
TRAVEL MOTOR (RIGHT)
AG
X
(3) CYLINDER GP
BUCKET
(2) CYLINDER GP
BOOM
STICK
SWING
BUCKET
BOOM
OUT
IN
L
R
OPEN CLOSE DOWN
UP
P1
P2
Pi1
P-IN PSA2 DR1 PSA1
T-OUT2 DR2
DR3 DR4 Pi2 DR5 DR6T-OUT1
B1
A1
A2
B2
OUT
T
PG
PC
IN
Pi1
PS1D0
A4 B1 Dr1 Di PS2 PB
Pi2
a2
a5
A2
a3
PSV
A1
a1
a4
aL5
Dr
HL
R2
X
dL5 (IN,OUT)(DOWN)(OPEN)bL2(FWD)
Pp1
PiH
dST1(FWD)(L)dSWPiL(IN)dR5APi2dR4
R1
Y
AR4
R3
HR
(UP)
aL4
ADr
APi
(OUT)
(R) (L)
(R)
(F)(B)
(BACK)
PSW PTA
(BACK)
(B) (F) PAT BL2 AL2aL2
(CLOSE)
(UP)
BDr
BPi
STICK(2)BOOMBUCKETATCHTRAVEL(R)TRAVEL(L)SWINGSTICKBOOM(2)
A
B
P1
P2
T
Pp2
TP
TT
BACK
T1 T2
FWD
FWD
T3 T4
BACK
JLP
JLT
JRP
JRT
JR1
JR3
JR2
JR4
JL4JL2
JL3
JL1
A1
B1
A2
B2
A3
B3
A4
B4
A5
B5
A6
B6
A7
B7
A8
B8
8
1
7
6
(31) VALVE GP
PILOT
MANIFOLD
215-5037
(5) FILTER GP
RETURN
173-3434
(6) FILTER GP
DRAIN RETURN
126-2075
(8) MOTOR GP
COOLING FAN
242-6904
(25) VALVE GP
CHECK
SLOW RETURN
185-0384
(24) VALVE GP
CHECK COOLER
BYPASS
123-2505
(29) VALVE GP
PILOT CONTROL
STICK/SWING
232-4157
(9) MOTOR GP
LEFT SWING
225-4506
(21) VALVE GP
BOOM/SWING
PRIORITY
232-4102
(7) FILTER GP
PILOT
158-8987
(1) ACCUMULATOR GP
PILOT MANIFOLD
164-6981
µ
µ µ
µµ
µ µ
µ
NO.1
(TRAVEL)
NO.2
(SWING)
NO.3
(LOCK)
bR1 aR1 aL1 bL1
aR3 bR3bR2 aR2aL3bL3 bL4aR4
BR3 AR3
AR2 BR2
BR1 AR1 AL1 BL1
BR3 AR3
aR3
BR2
AR2
BR1
AR1
bR2
bR1
bL1
BL1
AL1
bL3
bR3
aR2 aR1
PL
PR
aL1
aL3 bL4
PR
PL
aR4
µ
µ µ
µ
DR
DR1
L2
L3
A
B
S LL1
B
X
MU
A
CV2
MU1
A
CV
MU2
MU1
A
MU2
CV
(13) PUMP GP
COOLING
259-0814
(14) PUMP GP
DRIVE/IDLER/PILOT
259-0818
DRIVE
IDLER
PILOT
(14) VALVE GP
POWER SHIFT
CONTROL
225-4518
(6) FILTER GP
DRAIN RETURN
126-2075
(28) VALVE GP
PILOT CONTROL
BUCKET/BOOM
232-4158
(30) VALVE GP
PILOT CONTROL
TRAVEL
165-9522
(11) MOTOR GP
RIGHT SWING
225-4506
(9) VALVE GP
LEFT SWING
MOTOR
116-3420
(10) MOTOR GP
LEFT TRAVEL
232-6180
(26) VALVE GP
LEFT
TRAVEL/BRAKE
165-9338
(12) MOTOR GP
RIGHT TRAVEL
232-6180
(32) VALVE GP
RIGHT
TRAVEL/BRAKE
165-9338
(23) VALVE GP
MAIN CNTRL
230-2760
(23) VALVE GP
CHECK
BOOM/STICK (2)
239-8902
(23) VALVE GP
CHECK STICK
239-8904
(23) VALVE GP
CHECK
BOOM (2)
239-8906
(18) SWITCH AS
TRAVEL PRESS
106-0179
(17) SWITCH AS
IMPLEMENT
PRESSURE
106-0179
(15) SENSOR GP
DRIVE PUMP
PRESSURE
221-8869
(16) SENSOR GP
IDLER PUMP
PRESSURE
221-8869
(27) VALVE GP
LOCK SOL
121-1491
(34) VALVE GP
SWING BRAKE SOL
121-1491
(35) VALVE GP
TRAVEL
SPEED SOL
121-1491
(5) FILTER GP
RETURN
173-3434
(20) TANK GP
HYDRAULIC
227-0431
(22) VALVE GP
BOOM DRIFT
REDUCTION
153-5233
(33) VALVE GP
STICK DRIFT
REDUCTION
153-5233
MACHINE COMPONENT LOCATIONS
5
6
14
23
33
9
35
34
32
31
30
29
28
27
26
25
24
20
21
19
18
17
16
15
13
12
11
10
8
7
4
3
2
1
VIEW ALL CALLOUTS
MAIN CONTROL VALVE
AL4
BL4 AL3 AL2 AL1 AR1
BL3 BL2 BL1
PTA
PSW
X
BR2
AR4
AR3
BR3
BR1
AR2
Bpi
BDr
Pp2Pp1
Api
ADr
dsW PiL
STICK (2)
BOOM
BUCKET
ATT
TRAVEL (R) STR TRAVEL
TRAVEL (L)
SWING
STICK
BOOM (2)
33
22
VIEW ALL CALLOUTS
PILOT MANIFOLD CONTROL VALVE
DR2 T-OUT2
DR1
PSA1
PSA2
P-IN
Pi 1
P2
PAC
DR6
DR5
DR4 DR3
Pi 2
T-OUT1
LOCK SWING TRAVEL
VIEW ALL CALLOUTS
