cat schematic hydrauic system 525c

1. INTERACTIVE SCHEMATIC
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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
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2. Hydraulic System
©2012 Caterpillar, All Rights Reserved Printed in U.S.A.
RENR8898-01
May 2012
525C, 535C, and 545C Wheel Skidder
525C:
5251-692
535C:
5351-336
545C:
5451-455

3. COMPONENT LOCATION
Description
Part
Number
Machine
Location
Schematic
Location
4
-
F
1
2
3
2
8
-
8
3
2
e
k
a
r
B
t
n
o
r
F
-
p
G
r
o
t
a
l
u
m
u
c
c
A
6
-
C
2
1
3
5
8
-
0
7
1
d
l
o
f
i
n
a
M
t
o
l
i
P
-
p
G
r
o
t
a
l
u
m
u
c
c
A
4
-
F
3
1
4
9
9
-
9
3
2
e
k
a
r
B
r
a
e
R
-
p
G
r
o
t
a
l
u
m
u
c
c
A
4
-
F
4
9
5
7
3
-
I
7
e
k
a
r
B
g
n
i
k
r
a
P
-
s
A
r
o
t
a
u
t
c
A
6
-
F
5
1
2
9
1
-
0
6
2
e
k
a
r
B
t
o
o
F
-
p
G
l
o
r
t
n
o
C
Control Gp - Joystick (Grapple Control)
(525C Only) Single Function
Two Function
238-9805
238-9804
C-4
5
-
B
7
7
6
5
6
-
2
5
2
l
i
O
c
i
l
u
a
r
d
y
H
-
p
G
r
e
l
o
o
C
5
-
E
8
5
9
1
3
-
0
0
2
m
o
o
B
-
p
G
r
e
d
n
i
l
y
C
5
-
E
9
2
9
4
0
-
0
6
1
t
f
i
L
e
d
a
l
B
g
n
i
k
c
e
D
-
p
G
r
e
d
n
i
l
y
C
4
-
E
0
1
4
0
2
3
-
0
0
2
h
c
r
A
H
L
-
p
G
r
e
d
n
i
l
y
C
6
-
E
1
1
1
7
8
5
-
2
5
2
g
n
i
r
e
e
t
S
H
L
-
p
G
r
e
d
n
i
l
y
C
4
-
E
2
1
2
0
2
3
-
0
0
2
h
c
r
A
H
R
-
p
G
r
e
d
n
i
l
y
C
6
-
E
3
1
2
7
8
5
-
2
5
2
g
n
i
r
e
e
t
S
H
R
-
p
G
r
e
d
n
i
l
y
C
Cylinder Gp - Tong (525C)
(535C)
(545C)
226-7864
203-4209
276-1947
Filter Gp - Implement / Steering Return 214-6589
5
-
A
6
1
4
5
9
8
-
6
6
2
n
r
u
t
e
R
d
l
o
f
i
n
a
M
t
o
l
i
P
-
p
G
r
e
t
l
i
F
Pump Gp - Implement / Steering (525C/535C)
(545C)
6E-6012
161-5715
6
-
A
8
1
6
9
7
0
-
2
5
2
t
o
l
i
P
h
c
n
i
W
h
c
e
M
-
p
G
p
m
u
P
6
-
A
9
1
5
1
3
4
-
1
5
2
t
o
l
i
P
-
p
G
p
m
u
P
3
-
D
0
2
7
5
4
9
-
5
2
2
e
l
p
p
a
r
G
-
p
G
r
o
t
a
t
o
R
3
-
E
1
2
7
5
9
0
-
7
3
2
e
r
u
s
s
e
r
P
b
a
r
G
o
t
u
A
-
r
o
s
n
e
S
5
-
E
2
2
6
0
8
7
-
E
3
e
r
u
s
s
e
r
P
e
k
a
r
B
w
o
L
-
p
G
h
c
t
i
w
S
Switch Gp - Parking Brake Pressure 174-4312
3
-
A
4
2
8
2
6
8
-
0
2
2
l
i
O
c
i
l
u
a
r
d
y
H
-
p
G
k
n
a
T
3
-
D
5
2
0
0
7
0
-
8
7
1
r
e
d
i
v
i
D
w
o
l
F
-
e
v
l
a
V
Valve Gp - Accumulator Charging 9U-2886
4
-
B
7
2
4
0
2
1
-
2
3
1
k
c
e
h
C
-
p
G
e
v
l
a
V
Valve Gp - Check Imp / Steer Return 253-7537
Valve Gp - Check P-Manif Return 192-2684
1
-
C
8
2
4
6
3
6
-
7
5
2
d
i
o
n
e
l
o
S
l
o
o
p
S
e
e
r
F
-
p
G
e
v
l
a
V
Valve Gp - Grapple Control
(525C / 535C) Arch / Tong / Rotate
(525C / 535C) Arch / Tong / Rotate / Winch
(525C / 535C) Boom / Arch / Tong / Rotate
(525C / 535C) Boom / Arch / Tong / Rotate / Winch
(545C) Boom / Arch / Tong / Rotate
(545C) Boom / Arch / Tong / Rotate / Winch
195-5015
253-1763
195-5014
253-1770
195-0821
253-3348
4
-
F
0
3
2
4
7
0
-
2
5
2
e
k
a
r
B
g
n
i
k
r
a
P
-
p
G
e
v
l
a
V
6
-
C
1
3
3
0
6
4
-
3
5
2
d
l
o
f
i
n
a
M
t
o
l
i
P
-
p
G
e
v
l
a
V
6
-
C
2
3
2
6
7
1
-
3
5
2
l
o
r
t
n
o
C
r
e
z
o
D
/
r
e
e
t
S
-
p
G
e
v
l
a
V
3
-
B
3
3
5
4
1
4
-
T
4
r
e
k
a
e
r
B
f
e
i
l
e
R
k
n
a
T
-
p
G
e
v
l
a
V
1
-
F
4
3
6
0
2
5
-
2
5
2
c
i
l
u
a
r
d
y
H
-
p
G
h
c
n
i
W
5
-
A
5
3
2
4
7
9
-
7
7
1
g
n
i
r
e
e
t
S
y
r
a
d
n
o
c
e
S
-
p
G
p
m
u
P
6
-
B
6
3
7
1
4
3
-
1
2
2
e
r
u
s
s
e
r
P
r
e
e
t
S
/
p
m
I
-
r
o
s
n
e
S
7
-
C
7
3
2
2
3
9
-
3
8
1
r
e
e
t
S
/
p
m
I
k
c
e
h
C
-
p
G
e
v
l
a
V
7
-
C
7
3
3
1
0
1
-
T
9
g
n
i
r
e
e
t
S
c
e
S
k
c
e
h
C
-
p
G
e
v
l
a
V
Secondary Steering Attachments
Check Part Numbers in the Parts Manuals for your Specific Machine
3
-
C
9
2
6
14 E-3
15 A-4
17 A-7
5
-
F
6
2
4
-
A
7
2
4
-
A
7
2
3
-
E
3
2

4. TAP LOCATION
Tap
Number
Description
Schematic
Location
TP1 Imp/Steer Pump Discharge Pressure B-7
TP2 Imp/Steer Pump Signal Pressure B-7
TP3 Pilot Oil Pressure C-6
TP4 Pilot Differential Lock Pressure C-6
TP5 Rear Service Brake Accumulator Pressure E-5
TP6 Front Service Brake Accumulator Pressure F-5
TP7 Rear Service Brake Pressure F-7
TP8 Front Service Brake Pressure F-7
SOS Hydraulic Oil Sampling Port B-5

5. 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 PEDAL
GENERAL 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 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
A B
P T
A B
P T
SHIFTED POSITION INFINITE POSITION
CONTROL VALVES
ATTACHMENT
MANUAL SHUTOFF
SHUTTLE PILOT
CONTROLLED

6. 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

7. Components are shown installed on a fully operable machine with the key and engine off, transmission shifter
in neutral and with parking brake set.
Refer to the appropriate Service Manual for Troubleshooting, Specifications and Systems Operations.
SCHEMATIC PART NUMBER: 257-4985, CHANGE: 00, VERSION: -
MEDIA NUMBER: RENR8898-01
THIS SCHEMATIC IS FOR THE 525C, 535C, AND 545C WHEEL SKIDDER HYDRAULIC SYSTEM
A
B
C
D
F
1
2
3
4
5
E
6
7
A
B
C
D
F
E
1
2
3
4
5
6
7
LINE PATTERNS
Drain / Return Lines
Component Group
Pilot / Load Sensing Pressure
Pressure Line
Attachment
Air Line
CALLOUTS
Taps (Pressure, Sampling, Sensor - by letter)
YY
HYDRAULIC CIRCUIT COLOR DESCRIPTIONS
PILOT PUMP OUTPUT
IMPLEMENT AND STEERING PUMP OUTPUT
SECONDARY PUMP OUTPUT
DOZER CYLINDER CONTROL CIRCUIT
IMPLEMENT AND STEERING PUMP LOAD SENSE CIRCUIT
STEERING CIRCUIT
TONG CYLINDER CONTROL CIRCUIT
SUPPLY LINE
GRAPPLE MOTOR CIRCUIT
BRAKE CONTROL CIRCUIT
BOOM CYLINDER CONTROL CIRCUIT
HYDRAULIC WINCH CONTROL CIRCUIT
DRAIN / RETURN LINE
ARCH CYLINDER CONTROL CIRCUIT
MECHANICAL WINCH PILOT PUMP OUTPUT
(5) CONTROL GP
FOOT BRAKE
260-1921
(37) VALVE GP
CHECK
SEC STEERING
9T-1013
(37) VALVE GP
CHECK
IMP/STEER
183-9322
NOTE A
NOTE A
(36) SENSOR
IMP/STEER
PRESSURE
221-3417
(31) VALVE GP
PILOT
MANIFOLD
253-4603
(32) VALVE GP
STEER/DOZER
CONTROL
253-1762
(7) COOLER GP
HYDRAULIC OIL
252-6567
(27) VALVE GP
CHECK
132-1204
(24) TANK GP
HYDRAULIC OIL
220-8628
(15) FILTER GP
IMPLEMENT AND STEERING
RETURN
214-6589
(33) VALVE GP
TANK RELIEF
BREAKER
4T-4145
(6) CONTROL GP
JOYSTICK (GRAPPLE)
238-9805 (525C ONLY) SINGLE FUNCTION
238-9804 TWO FUNCTION
(29) VALVE GP
GRAPPLE CONTROL
195-5015 (525C/535C) ARCH/TONG/ROTATE
253-1763 (525C/535C) ARCH/TONG/ROTATE/WINCH
195-5014 (525C/535C) BOOM/ARCH/TONG/ROTATE
253-1770 (525C/535C) BOOM/ARCH/TONG/ROTATE/WINCH
195-0821 (545C) BOOM/ARCH/TONG/ROTATE
253-3348 (545C) BOOM/ARCH/TONG/ROTATE/WINCH
(28) VALVE GP
FREE SPOOL
SOLENOID
257-6364
(20) ROTATOR GP
GRAPPLE
225-9457
(21) SENSOR
AUTO GRAB
PRESSURE
237-0957
(25) VALVE
FLOW DIVIDER
178-0700
(14) CYLINDER GP
TONG
226-7864 (525C)
203-4209 (535C)
276-1947 (545C)
(23) SWITCH GP
PARKING BRAKE
PRESSURE
174-4312
(10) CYLINDER GP
LH ARCH
200-3204
(12) CYLINDER GP
RH ARCH
200-3202
(8) CYLINDER GP
BOOM
200-3195
(22) SWITCH GP
LOW BRAKE
PRESSURE
3E-7806
(9) CYLINDER GP
DECKING BLADE LIFT
160-0492
(13) CYLINDER GP
RH STEERING
252-5872
(11) CYLINDER GP
LH STEERING
252-5871
(26) VALVE GP
ACCUMULATOR
CHARGING
9U-2886
(1) ACCUMULATOR GP
FRONT BRAKE
238-8232
(3) ACCUMULATOR GP
REAR BRAKE
239-9941
(30) VALVE GP
PARKING BRAKE
SOLENOID
252-0742
(4) ACTUATOR AS
PARKING BRAKE
7I-3759
(17) PUMP GP
IMPLEMENT/
STEERING
6E-6012 (525C/535C)
161-5715 (545C)
(19) PUMP GP
PILOT
251-4315
(35) PUMP GP
SECONDARY STEERING
177-9742
NOTE A
(18) PUMP GP
MECH WINCH
PILOT
252-0796
NOTE A
(16) FILTER GP
PILOT MANIFOLD
RETURN
266-8954
(27) VALVE GP
CHECK
P-MANIF
RETURN
192-2684
(27) VALVE GP
CHECK
IMP/STEER
RETURN
253-7537
(2) ACCUMLATOR GP
PILOT MANIFOLD
170-8531
(34) WINCH GP
HYDRAULIC
252-5206
FRONT AXLE
REAR AXLE
TP7
TP8
TP6
TP5
WINCH
BRAKE
BRAKE
VALVE
FREESPOOL
NOTE A: FOR SECONDARY STEERING MACHINES ONLY.
SOS
AIR RELIEF
AIR VACUUM
TP1
TP2
TP3 TP4
LEFT
STEERING
DOZER
RAISE
RAISE
ARCH
RAISE
TONG
OPEN
BOOM
M
T
G
BR
DR
A
B
C
B A A
B A
B
B A B A
LS A
B A
B
LS
U

8. MACHINE COMPONENT LOCATIONS
37
37
36
36
35
35
34
33
33
33
32
32
31
31
30
30
29
29
28
28
27
27
26
26
25
25
24
24
23
23
22
22
21
21
20
19
19
18
18
17
17
16
16
15
15
14
13
13
12
11
11
10
9
9
9
8 7
7
6
5
5 4
4
3
3
2
2 1
1
VIEW ALL CALLOUTS

9. BRAKE ACCUMULATOR TEST PORTS
SOS
TP6 TP5 30
26
23
16
3
1
VIEW ALL CALLOUTS

10. IMP/STEER PUMP TEST PORTS
FRONT VIEW
FRONT
FRAME
SOS
TP2
TP1
32
24
17
16
15
VIEW ALL CALLOUTS

11. PILOT MANIFOLD TEST PORTS
TP4
TP3
31
2
VIEW ALL CALLOUTS

12. SERVICE BRAKE TEST PORTS
TP8
TP7
VIEW ALL CALLOUTS