INTERACTIVE SCHEMATIC
The Bookmarks panel will allow you to
quickly navigate to points of interest.
Click on any text that is BLUE and underlined.
These are hyperlinks that can be used to navi-
gate the schematic and machine views.
When only one callout is showing on a machine view this
button will make all of the callouts visible. This button is
located in the top right corner of every machine view page.
VIEW ALL CALLOUTS
Cover Page
Information
Schematic
Machine Views
Component Table
Tap Table
Fluid Power Symbols
Electrical Symbols
Front Frame
Rear Frame
Tap Views
Features
Options
Bookmarks
X
EC-C3
EC-C2
E-C60
EC-C1
E-C61
To set your screen resolution do the following:
RIGHT CLICK on the DESKTOP.
Select PROPERTIES.
CLICK the SETTINGS TAB.
MOVE THE SLIDER under SCREEN RESOLUTION
until it shows 1024 X 768.
CLICK OK to apply the resolution.
This document is best viewed at a
screen resolution of 1024 X 768.
FUNCTION
Zoom In
HOTKEYS (Keyboard Shortcuts)
Zoom Out
Fit to Page
Hand Tool
“CTRL” / “+”
KEYS
“CTRL” / “-”
“CTRL” / “0” (zero)
“SPACEBAR” (hold down)
Find
“CTRL” / “F”
©
2011 Caterpillar, All Rights Reserved
Printed in U.S.A.
KENR6122-09
October 2011
Universal Quick Coupler
320D, 321D, 323D, 324D, 325D, 329D
Hydraulic System - Attachment
323D:
RAC1-UP
SDC1-UP
WGC1-UP
CYD1-UP
SED1-UP
YSD1-UP
NDE1-UP
WNE1-UP
ZMF1-UP
JLG1-UP
BYM1-UP
PBM1-UP
NES1-UP
DKW1-UP
SBZ1-UP
320D:
A6F1-UP
A8F1-UP
A9F1-UP
KGF1-UP
MCH1-UP
TDH1-UP
FAL1-UP
KLM1-UP
SPN1-UP
WBN1-UP
GDP1-UP
PCX1-UP
PHX1-UP
325D:
GPB1-UP
PKE1-UP
LAL1-UP
MCL1-UP
AZP1-UP
A3R1-UP
GBR1-UP
T2S1-UP
CYW1-UP
330D:
GGE1-UP
B6H1-UP
THJ1-UP
LRM1-UP
ERN1-UP
JLP1-UP
MWP1-UP
RAS1-UP
EDX1-UP
T2Y1-UP
324D:
EJC1-UP
MND1-UP
T2D1-UP
JJG1-UP
BTK1-UP
SYM1-UP
JAT1-UP
321D:
TXA1-UP
PBD1-UP
NAS1-UP
329D:
XDB1-UP
BFC1-UP
CZF1-UP
JBF1-UP
WDK1-UP
EBM1-UP
TPM1-UP
YFW1-UP
SCY1-UP
DTZ1-UP
336D:
J2F1-UP
LMG1-UP
MYG1-UP
KDJ1-UP
WRK1-UP
PPN1-UP
MYP1-UP
JWR1-UP
DTS1-UP
WET1-UP
PGW1-UP
330D, 336D and 336D MHPU Excavator
336D MHPU:
M3M1-UP
M3N1-UP
COMPONENT LOCATION
Accumulator Gp 164-6981
20
B-4
Block 187-6716
21
D-7
Cylinder Gp - Boom Note A
22
E-6
Cylinder Gp - Bucket Note A
23
E-7
Cylinder Gp - Stick Note A
24
E-7
Filter Gp - Case Drain 126-2075
25
A-6
Filter Gp - Pilot Hydraulic 188-2084
26
A-3
Filter Gp - Return Oil 188-4140
27
A-6
Manifold Gp - Control 215-5037
28
B-5
Motor Gp - Swing 158-8986
29
F-5
Motor Gp - Travel Left 215-9952
30
F-4
Motor Gp - Travel Right 215-9952
31
F-3
Pump GP - Main Hydraulic 272-6955
32
B-2
Sensor As - Left Pump Pressure 221-8859
33
B-3
Sensor As - Right Pump Pressure 221-8859
34
A-3
Switch As - LH Travel Pressure 167-3466
35
D-7
Switch As - Pilot Pressure 167-3466
36
B-7
Switch As - RH Travel Pressure 167-3466
37
D-6
Swivel Gp 234-4440
38
E-4
Tank Gp - Hydraulic Oil 245-5141
39
A-4
Valve Gp - Cooler Bypass 173-4672
40
B-7
Valve Gp - Heavy Lift Solenoid 121-6303
41
B-3
Valve Gp - LH Joystick 232-4100
42
C-7
Valve Gp - Load Control Boom Cylinder 255-5683
43
D-2
Valve Gp - Load Control Stick Cylinder 255-5680
44
D-5
Valve Gp - Main Control 259-7602
45
C-4
Valve Gp - Pilot Travel 158-8250
46
D-7
Valve Gp - Press Reducing Boom/Swing 232-4102
47
B-3
Valve Gp - RH Joystick 225-4813
49
C-6
Valve Gp - Shuttle 185-0462
50
C-7
Valve Gp - Swing Cushion 322-8716
51
E-5
Valve Gp - Travel LT Counterbalance 204-2819
52
E-4
Valve Gp - Travel RT Counterbalance 204-2819
53
E-3
NOTE A: Check the parts manual for the correct cylinder part number.
Valve Gp - Press Reducing Boom/Swing 232-4102
48
B-4
Standard Machine
Description
Part
Number
Machine
Location
Schematic
Location
Valve Gp - Check (Quick Coupler) 123-4750
2
B-2
Attachment: Universal Quick Coupler
Valve Gp - Shuttle (Quick Coupler) 123-2549
3
C-5
Valve Gp - Quick Coupler 254-3080
4
E-2
Valve Gp - Solenoid (Quick Coupler) 258-6749
5
E-2
Connector As - Quick Coupler 148-8321
1
E-2
TAP LOCATION
Tap
Number
Description
Schematic
Location
EE
Left Pump Delivery Pressure
B-2
FF
Right Pump Delivery Pressure
A-2
GG
Pilot Pump Delivery Pressure
A-3
HH
Left Pump Power Shift Pressure
B-2
JJ
Case Drain Pressure
B-2
KK
Right Pump Power Shift Pressure
A-2
LL
Quick Coupler Unlock Pressure
F-3
MM
Quick Coupler Lock Pressure
F-2
SOS
Hydraulic Oil Sampling Port
A-3
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
HYDRAULIC CIRCUIT COLOR DESCRIPTIONS
RIGHT MAIN PUMP OUTPUT
LEFT MAIN PUMP OUTPUT
LEFT & RIGHT MAIN PUMP POWERSHIFT CIRCUIT
PILOT PUMP OUTPUT
ATTACHMENT CONTROL CIRCUIT
SUPPLY LINE
BUCKET CYLINDER CONTROL CIRCUIT
RIGHT TRAVEL MOTOR CONTROL CIRCUIT
TRAVEL SPEED CONTROL CIRCUIT
STICK CYLINDER CONTROL CIRCUIT
BOOM CYLINDER CONTROL CIRCUIT
HEAVY LIFT CONTROL CIRCUIT
LEFT TRAVEL MOTOR CONTROL CIRCUIT
SWING MOTOR CONTROL CIRCUIT
SWING BRAKE CONTROL CIRCUIT
THIS SCHEMATIC IS FOR THE 320D, 321D, 323D, 324D,
325D, 329D, 330D, 336D, and 336D MHPU EXCAVATOR
ATTACHMENT: UNIVERSAL QUICK COUPLER
MEDIA NUMBER: KENR6122-09
PART NUMBER: 262-3421, CHANGE: 02, VERSION: HE
Components are shown installed on a fully operable machine.
Refer to the appropriate Service Manual for Troubleshooting, Specifications.
A
B
C
D
E
F
1234567
A
B
C
D
E
F
1234567
FF
HH
JJ
KK
MMLL
SOSGG
EE
P
TRAVEL(L)
TRAVEL(R)
T1
T5
BACK
FWD
BACK
FWD
T2
T4
T6
T3
JLP
JLT
STICK
SWING
OUT
JL1
IN
JL3
R
L
JL2
JL4
BUCKET
BOOM
OPEN
CLOSE
DOWN
UP
JR1
JR2
JR3
JR4
A1
A2 A3 A4 A5 A6 A7 A8
B1 B2
B3
B4
B5
B6
B7
B8
TRAVEL MOTOR (LEFT) TRAVEL MOTOR (RIGHT)
T
Pp3
Pp3
T
A
B
A
B
(24) STICK
CYLINDER
(22) BOOM
CYLINDER
(23) BUCKET
CYLINDER
M2
G2
G1
M1
A3
A1
S1
S3
A2
Pm
Pi
Pn1
Pn2
Ps1
PsM1
G3
Dr1
Dr2
G2
PsM2
P2
Pi1
P1
DR1
DR2
DR3
DR4
DR5
DR6
P-IN
PSA1
PSA2
T-OUT1
T-OUT2
Pi2
HL
Di2
STICK(2)
BOOM(1)
ATCH
BUCKET
TRAVEL(R)
TRAVEL(L)
SWING
STICK(1)
BOOM(2)
Pi2
Pi3
Di3
DST
PL
PR
bR2
Di1
HR
T
AL4
aL4
SPi
SDr
SP3
Di4
Pi4
Pi1
BP3
BDr
BPi
BP2
R3
aR5
AR5
BR5
AR2BR2
aR2
(UP)
(OUT)
(IN)
(R)
(L)
(FWD)
(REV)
(FWD)
(REV)
(OPEN)
(CLOSE)
(UP)
(DOWN)
(OUT)
PG
DR
MU
AB
SWING MOTOR
P1
P2
T
A1 A2B1 B2
aL3
A
C
B
D
E
F
G
JRP
JRT
bR5
INOUT
T
DR
A1
B1
A
T
P
Pi5
TT
TP
PG
PC
U
RR
FR
µ
µ µ
µ
aL1 bL1 bR1 aR1
AL3 BL3
AR4 BR4AR3 BR3
AL2BL2
aR3
aR4 bR3 bR4
bL3
bL2 bL4 aL2
bL3 bL2
bL1 bR1 bR3
bR4
BL3
AL3
AL1
AL2
BL1
BL2
aL2
aR1
AR1
BR1
AR3BR3 BR4
AR4
aL1 aR3
aR4
NO.1
(TRAVEL)
NO.2
(SWING)
NO.3
(LOCK)
bL4
AR1BR1AL1BL1
µ
µ µ
µµ
µ µ
µ
(33) SENSOR AS
LEFT PUMP
PRESSURE
221-8859
Ps2
(34) SENSOR ASSEMBLY
RIGHT PUMP PRESSURE
221-8859
(37) SWITCH AS.
RH TRAVEL PRESSURE
167-3466
(35) SWITCH AS.
LH TRAVEL
PRESSURE
167-3466
(36) SWITCH AS.
PILOT PRESSURE
167-3466
(50) VALVE GP
SHUTTLE
185-0462
(42) VALVE GP
LH JOYSTICK
232-4100
(49) VALVE GP
RH JOYSTICK
225-4813
(46) VALVE GP
PILOT TRAVEL
158-8250
(21) BLOCK
187-6716
(26) FILTER GP
PILOT HYDRAULIC
188-2084
(40) VALVE GP
COOLER BYPASS
173-4672
(27) FILTER GP
RETURN OIL
188-4140
(39) TANK GP
HYDRAULIC OIL
245-5141
(25) FILTER GP
CASE DRAIN
126-2075
(41) VALVE GP
HEAVY LIFT
SOLENOID
121-6303
(20) ACCUMULATOR GP
164-6981
(28) MANIFOLD GP
CONTROL
215-5037
(47) VALVE GP
PRESS REDUCING
BOOM/SWING
PRIORITY
232-4102
(32) PUMP GP
MAIN HYDRAULIC
272-6955
(43) VALVE GP
LOAD CONTROL
BOOM CYLINDER
255-5683
(45) VALVE GP
MAIN CONTROL
259-7602
(44) VALVE GP
LOAD CONT. STICK CYLINDER
255-5680
(38) SWIVEL GP
234-4440
(31) MOTOR GP
TRAVEL RIGHT
215-9952
(53) VALVE GP
TRAVEL RT
COUNTERBALANCE
204-2819
(52) VALVE GP
TRAVEL LT
COUNTERBALANCE
204-2819
(29) MOTOR GP
SWING
158-8986
(51) VALVE GP
SWING
CUSHION
322-8716
FINE
SWING
P1
P2
T
A1 A2B1 B2
T
dr1 Pp
dr2
b
B A
UNLOCK LOCK
a
A
P
dr
(4) VALVE GP
QUICK COUPLER
254-3080
(5) VALVE GP
SOLENOID
(QUICK COUPLER)
258-6749
(2) VALVE GP
CHECK (QC)
123-4750
(3) VALVE GP
SHUTTLE (QC)
123-2549
(48) VALVE GP
PRESS REDUCING
BOOM/SWING
PRIORITY
232-4102
VALVE GP
PRESS REDUCING
(BOOM UP PRIORITY)
(1) CONNECTOR AS. (QC)
148-8321
(30) MOTOR GP
TRAVEL LEFT
215-9952
(52) VALVE GP - CONTROL
138-1234
Callout Number
(Machine Location from
Component Locations Table
Component
Name
Part Number
MACHINE COMPONENT LOCATIONS
53
53
52
52
51
51
50
50
49
49
48
48
47
47
46
46
45
45
44
44
43
43
42
42
41
41
40
40
39
39
38
38
37
37
36
36
35
35
34
34
33
33
32
32
31
31
30
30
29
29
28
28
27
27
26
26
25
25
24
24
23
23
22
22
22
21
21
20
20
5
5
4
4
3
3
2
2
1
1
VIEW ALL CALLOUTS
CONTROL MANIFOLD
LOCK
SOLENOID
SWING
SOLENOID
TRAVEL
SPEED
SOLENOID
28
MAIN CONTROL VALVE
BOOM(2)
STICK(1)
SWING
TRAVEL (L)
STR TRAVEL
TRAVEL (R)
ATTACHMENT
BUCKET
BOOM(1)
STICK(2)
45
MAIN PUMP AND FILTER CIRCUITS
HYD.
TANK
SOS
KK
JJ
HH
GG
FF
EE
34
33
32
27
26
25
VIEW ALL CALLOUTS
QUICK COUPLER CIRCUIT
FWD
MM
MM
LL
LL
EE
45 38
32
32
28
5
4
3
3
2
2
VIEW ALL CALLOUTS
