26
39 GW
6
112 WR
59 108 LW
56
74
58
B
61
B
110 G 20R
20B
B 14
113 OW
1
2WR
S
B
109 LO
M
2
5R 7
9
63 B
111 GL
51 YG
60
62
47 9
8
5R
64 BAT
11 WY 54 52 2
2
68 9
106 W 105 LG
101
GW
52 YR
IC REG
B
YB
50 GW
IG
L
81 O
1
55
P
69
5
WY 54 PL
1
B
6
B
WG
10
47 3LY
53
5
51 31
W 70 2BR
4
55 YL B
107 WR
B
92 L
HOLD
PULL
71
B 50
6
100 Lg E
49
2B
72 4
B
RG
15
12 20
R +1
11
2
YB
B
GAUGE CLUSTER
5
3
B
4 WG
6
1
WY
87 1.25 BrR
86
B
LgR
B 67
21
RG
1 WY
5
POSITION
POSTION
10A
45
38 8
2R
27 8
71 3Y 7
2RB 72 L POSITON
PREHEATING
1 WY
5R
11 WY
E 42
5R
POSITION
6
43 R2
7
ACC
5
2RB
5
2W 5
70
2BR
B
3
ON
25
51 YG
86 LgR
E
ENG. OIL PRESS.
2 3
50 GW 48 LgB
B 2
3
YG
3
YG
FUEL METER
11
TERMO METER 1
13
ILLUMINATION
12
6
56 YB
26
32 39
GW
B
52 YR 63
B
BY
64 LW
A
28
B
33 B
60 GY
AIR FILTER RESTRICTION 9
1 WY
M
M
P1
21 WB
H
B
2
YB
19
P2
61 LB
16 RW
13 BW
C
W
15 YG
W
72 L
BR
2W
5
TERMINAL
58 GB
22 BR
E 40
10
20 G
39
47 3LY
2
6
L
WG
47 3LY
R1
4
CHARGE
WASHER ON
8
6
57 LB
OFF
L 8
OFF
AC
B
7
EMPTY
19 LB
WASHER
P
C
START
ON
OFF
TERMINAL
TWO-SPEED
POSITION
S
B
5
18 LY
M 8
WG
ENG. WATER TEMP.
L
14 2WR
3R
6
B
E
4
37 6
22
POSITION
18
WG
2W
B
17 PB
1.25 YG
17
44
30A
3
3
6
ENG. STOP SOL.
HORN, ROOM LAMP 4
WORK LIGHT 2RG
B
HI
30A
66
1
2
LO
30A
16
14
13
B 30A
81 O
B
M
57
OFF
2YG
2
3
RELAY,SOL
RADIO, HEATER, WIPER 1
- B +B L
75
WY 1.25 YB
65
M
R B
M
Y S
46
30A
73
70
8
29
36 23
41
4
86
LgR
H EM
1.25
2
48 2B
E
49 P
6
2B
WG
1
4
30
61 LB 45 BW
B
HOLD B
6
2 3 5
HOLD
43
34
YB
Lg
46 WB
24 2
35 B
COMPONENTS
1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15.
BATTERY (E-13) STARTER MOTOR (M-1) DIODE (D-1) AIR HEATER (E-8) GENERATOR (E-2) ENGINE STOP SOLENOID (SV-3) ENGINE WATER TEMP SWITCH (SW-5) ENGINE OIL PRESS SWITCH (SW-6) COOLANT THERMO SENSOR (SE-2) AIR FILTER RESTRICTION SWITCH (SW-14) NORTH AMERICAN AND AUSTRAILIA: STANDARD HEATER (OPTIONAL) (E-12) WIPER MOTOR (FOR CAB) (M-2) WASHER MOTOR (FOR CAB) (M-3) HORN (E-3) CAB LAMP (L-1)
16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31.
RADIO (FOR CAB OPTION) (E-10) HORN SWITCH (SW-7) GAUGE CLUSTER (E-6) CHARGE INDICATOR RELAY (R-8) DIODE (D-2) FUEL SENSOR (SE-1) INDICATOR (OPTION) (C-8) (NOT SHOWN) DIODE (D-3) DIODE (D-4) BOOM WORKING (L-2) LIGHT LEFT (55W) LEVER LOCK SWITCH (SW-9) DIODE (D-12) DECEL RELAY (R-3) CRANE TIMER RELAY (OPTION) (R-20) (NOT SHOWN) DECEL SWITCH (SW-11) DIODE (D-13)
32. OPERATING LEVER LOCK SOLENOID (SV-1) 33. DECEL MOTOR (M-4) 34. TWO-SPEED SELECT SOLENOID (SV-2). 35. TWO-SPEED SELECT SW (SW-3). 36. SEQUENCE BOX (E-14) 37. WORKING LIGHT SWITCH (SW-2) 38. HEATER SWITCH (OPTION) (SW-10) 39. WIPER WASHER SWITCH (FOR CAB) (SW-4) 40. ENGINE STOP RELAY (R-7) 41. TIMER UNIT (R-6) 42. SAFETY RELAY (R-2) 43. KEY SWITCH (SW-1) 44. BATTERY RELAY (R-1) 45. FUSE BOX (E-1) 46. FEED PUMP (M-6) 47. FUSIBLE LINK (45A) (E-4)
48. HOUR METER (E-26) 49. SLEW/SWING PRESERVATION RELAY (R-23) (NORTH AMERICA: STANDARD) 50. SLEW/SWING LEVER PRESSURE SWITCH LEFT (SW-30) 51. SLEW/SWING LEVER PRESSURE SWITCH RIGHT (SW-31) 52. SWITCH SELECT RELAY (R-22) 53. SLEW/SWING SELECT SWITCH (SW-28) 54. SLEW/SWING SELECT RELAY (R-14) 55. SLEW/SWING SELECT SOLENOID (SV-12) 56. NIBBLER OPEN SWITCH (SW-33) 57. DIODE (D-14) 58. NIBBLER OPEN RELAY (R-24) 59. NIBBLER OPEN SOLENOID (SV-9) 60. NIBBLER CLOSE SOLENOID (SV-10) 61. NIBBLER CIRCUIT 62. LEVER CLOSE RELAY (R-25)
CIRCUIT DIAGRAM LEGEND
SHOWS CIRCUIT CROSSING NOT CONNECTED
SHOWS CIRCUIT CONNECTED
54 COMPONENT NUMBER
COMPONENT OUTLINE
6
6
TO
FROM
NUMBER REFERS TO CONTINUATION OF A CIRCUIT
63. 64. 65. 66. 67. 68. 69. 70. 71. 72. 73. 74. 75.
NIBBLER CLOSE SWITCH (SW-34) SLEW SWING CIRCUIT WORK LIGHT CIRCUIT WORK LIGHT RELAY (R-9) CAB/CANOPY WORKING LIGHT (L-5) TRAVEL ALARM NORTH AMERICAN OPTION TRAVEL RIGHT (FORWARD) PRESSURE SWITCH (SW-24) TRAVEL RIGHT (REVERSE) PRESSURE SWITCH (SW-25) TRAVEL LEFT (FORWARD) PRESSURE SWITCH (SW-26) TRAVEL LEFT (REVERSE) PRESSURE SWITCH (SW-27) TRAVEL ALARM (E-20) ENGINE INST PANEL AND RELAY ASSY. (PART IN RELAY CONSOLE)
WIRE IDENTIFICATION 6 FROM FUSE PANEL
INDICATES EXTERNAL GROUND
INDICATES INTERNALLY GROUNDED COMPONENT
6 WIRE NUMBER WIRE SIZE
2 R WIRE COLOR
B . . Black Br . . Brown G . . Green Gr. . Gray L. . . Blue
NOTES Lg. . Light Green O . . Orange P . . Pink R . . Red Sb . Sky Blue
V . . Violet W . . White Y . . Yellow
1. Diagram shown with vehicle parked, power OFF, and controls in OFF or NEUTRAL position.
ELECTRICAL SCHEMATIC EH27.B HYDRAULIC EXCAVATORS Additional copies of this Hydraulic and Electrical Schematic can be ordered through Technical Publications Distribution System. The Part Number is 6-78330
GROUND BCO4N067
NEUTRAL CIRCUIT
TRAVEL CIRCUIT - TRAVEL FORWARD OPERATION AT TRAVEL 2ND SPEED 4 A1G A1
R1
A1
A2
A2 A2G A4
Ps
404
A3
9
4
Ps
4
404 405
406
T1,T2
T1,T2
13
P2
401
406
405
5
P2
401
DB
1 T1
P2
19
P1
7
403
30
401
B
8
P2
303
D
19
402 P1
301
P1
7
403
30
B
304 R2
A
A
M
29
303
R1
305 305
C
A C F E
PG
B
A
M
29 A
B
28
304
SH D
B D GH
29
B
8
10
305 PG
15
S1
C
A C F E
302
R1
305
3
24 402
304
SH
DB
23
304 R2
10
22
5
P2
403
15 A
A
405
P1
P
S1
29
P2
406
6
301
P1
B D GH
T1,T2
T1,T2
13-1
402
403
406
T1
24 402
404 405
1 302
P1
P
404
A3
401
6
13-1
A2 A2G A4
9
4
Ps
13
3
23
A1G A1
R1
A1
A2
22
Ps
B
28 27
O
27
O
S A2B2 A1 B1
S A2B2 A1 B1
S
S PP P2 P SW31
PP P2 P SW31
P1 P SW30
25
P1 P SW30
25
16
16
3 7 4 8
21
B10
A10
Pa10
2 Pb8 Dr1 B9
B8 Pa8
B7
A7 Pa7
P1
Pa6
P2
A6
B6
Pa5
A5
B5
Pa4
B4
A4
Pa3
A3
P3 B2
B3
A2 Pa2
B1
3 7 4 8 D
A1 Pa1
20
21
B10
11 2 4 MRV1
3
1
2 4
2 Pb8 Dr1 B9
B8 Pa8
B7
A7 Pa7
P1
Pa6
P2
A6
B6
Pa5
A5
B5
Pa4
B4
A4
Pa3
A3
P3 B2
B3
2 4 MRV1
18
17
26
201
MRV3
201
203
18
204
17
26
201
MRV3 204
203 204
P
P
T
204
T T
P
204
14
204
2 Pb8
T2
Pb6
Pb7
Pb5
Pb4
T1
Pb3
Pb2
P
P Pb10
Pb1
Pb8
T2
Pb6
Pb7
Pb5
Pb4
T1
Pb3
3
4
1
2
A1G A1
R1
A2 A2G A4
Ps
404
A3
9
4
Ps
4
404 405
406
T1,T2
T1,T2
13
P2
401
406
405
5
P2
401
DB
T1
19
P1
T1,T2
T1,T2 P2
406
405
7
403
401
P2
R2 A
B
8
10
19
402 P1
301
P1
7
403
30
303 305
D
A
R1
A
M
29
304
303 SH
305
D B D GH
29
B
8
10
305 B
304 R2
C PG
15
S1
304
SH
A C F E
302
304
S1
3
24 402 403
15
DB
23
P1
P
30
22
5
P2
6
301
P1
B D GH
406
13-1
402
403
404 405
T1
24 402
404
A3
401
302
P1
A
12
9
4
Ps
1
6
13-1
A2 A2G A4
Ps
13
3
23
A1G A1
R1
A1
A2
22
1
29
3
4
1
BUCKET CIRCUIT - BUCKET DIGGING OPERATION 4
P2
T
Pb1
12
SLEWING CIRCUIT - SLEWING LEFT OPERATION
P
Pb2
Pp1
2
A1
T
204
T
Pp1
A2
P
T
204
14
2 P
Pb10
11
3
1
202
204
T
2 4
204
204 P
3
1
MRV2
202 201
D
A1 Pa1
11
MRV2
203
B1
206
204 203
A2 Pa2
3 7 4 8
11
3
1
Pa10
20
3 7 4 8
206
A10
R1
305
C
A C F E
PG
B
A
M
29 A
B
B
28
28 27
O
27
O
S A2B2 A1 B1
S A2B2 A1 B1 S
S
PP
PP P2 P SW31
P2 P SW31
P1 P SW30
25
P1 P SW30
25
16
16 3 7 4 8
3 7 4 8
21
B10
A10
Pa10
2 Pb8 Dr1 B9
B8 Pa8
B7
A7 Pa7
P1
P2
Pa6
A6
B6
Pa5
A5
B5
Pa4
A4
B4
Pa3
A3
P3 B2
B3
A2 Pa2
B1
D
A1 Pa1
20
21
B10
11 2 4 MRV1
3
1
2 4
3
1
Pa10
2 Pb8 Dr1 B9
B8 Pa8
B7
A7 Pa7
P1
P2
Pa6
A6
B6
Pa5
A5
B5
Pa4
A4
B4
Pa3
A3
P3 B2
B3
201
203
26
2 4
206
MRV2
MRV1
MRV3
201
203
18
204
17
26
201
P
T
MRV3
204
T P
204
2 T2
Pb8
Pb7
Pb6
Pb5
Pb4
Pb3
T1
Pb2
T
14
P
P Pb10
Pb1
T2
Pb8
Pb6
Pb7
Pb5
Pb4
Pb3
T1
8. 9. 10. 11. 12. 13. 14.
SWING CYLINDER DOZER CYLINDER SWIVEL JOINT PILOT VALVE (ATT) PILOT VALVE (TRAVEL) SOLENOID VALVE PILOT VALVE (DOZER)
15. 16. 17. 18. 19. 20. 21.
COMPONENT IDENTIFICATION SHUTTLE VALVE 22. NIBBLER CYLINDER MULTI CONTROL VALVE 23. STOP VALVE RETURN FILTER (ELEMENT) 24. SELECTOR VALVE SUCTION STRAINER 25. OIL COOLER INLINE FILTER 26. HYDRAULIC OIL TANK CHECK VALVE 27. SOLENOID VALVE HYDRAULIC RESERVOIR VENT 28. SOLENOID VALVE
29. ORIFICE
Pb2
T
Pb1
Pp1
2
PUMP ASSEMBLY CONTROL VALVE SLEWING MOTOR TRAVEL MOTOR BOOM CYLINDER / CANOPY CAB ARM CYLINDER BUCKET CYLINDER
T
204
T
Pp1
1. 2. 3. 4. 5. 6. 7.
P
T
204
2 P
Pb10
11
204 P
204
14
3
1
204
203
204
T
2 4
202
204 P
3
1
MRV2
204
201
203
D
A1 Pa1
11
11
202
17
B1
3 7 4 8
204
18
A2 Pa2
20
3 7 4 8
206
A10
1
4
3
2
12
1. 2. 3. 4. 5. 6.
NOTES 201 (MAIN RELIEF VALVE P1,P2) 23.0 MPa (3340 psi) 202 (MAIN RELIEF VALVE P3) 23.0 MPa (3340 psi) 203 (OVERLOAD RELIEF VALVE) 27.5 MPa (4000 psi) 204 (OVERLOAD RELIEF VALVE) 25.5 MPa (3700 psi) 304 (SLEW RELIEF VALVE) 18.5 MPa (2680 psi) 13-1 (PILOT RELIEF VALVE) 3.5MPa (508 psi)
1
4
3
12
HYDRAULIC SYMBOLS PRESSURE PILOT MAIN PRESSURE PILOT SEC PRESSURE CASE DRAIN COMPONENT
CHECK VALVE
54 COMPONENT NUMBER
SHOWS CIRCUIT CROSSING NOT CONNECTED
SHOWS CIRCUIT CONNECTED
FILTER OR SCREEN
HYDRAULIC SCHEMATIC EH27.B HYDRAULIC EXCAVATORS Additional copies of this Hydraulic and Electrical Schematic can be ordered through Technical Publications Distribution System. The part number is 6-78330
RESTRICTOR
OIL COOLER BC04N064
BOOM CIRCUIT - BOOM-UP OPERATION
ARM CIRCUIT - ARM-IN OPERATION 4 A1G A1
R1
A1
A2
A2 A2G A4
Ps
404
A3
9
4
Ps
4
404 405
406
T1,T2
T1,T2
13
P2
401
406
405
5
P2
401
DB
1 T1
P2
19
P1
7
403
30
401
B
8
P2
303
D
19
402 P1
301
P1
7
403
30
B
304 R2
A
A
M
29
303
R1
305 305
C
A C F E
PG
B
A
M
29 A
B
28
304
SH D
B D GH
29
B
8
10
305 PG
15
S1
C
A C F E
302
R1
305
3
24 402
304
SH
DB
23
304 R2
10
22
5
P2
403
15 A
A
405
P1
P
S1
29
P2
406
6
301
P1
B D GH
T1,T2
T1,T2
13-1
402
403
406
T1
24 402
404 405
1 302
P1
P
404
A3
401
6
13-1
A2 A2G A4
9
4
Ps
13
3
23
A1G A1
R1
A1
A2
22
Ps
B
28 27
O
27
O
S A2B2 A1 B1
S A2B2 A1 B1
S
S PP P2 P SW31
PP P2 P SW31
P1 P SW30
25
P1 P SW30
25
16
16
3 7 4 8
21
B10
A10
Pa10
2 Pb8 Dr1 B9
B8 Pa8
B7
A7 Pa7
P1
Pa6
P2
A6
B6
Pa5
A5
B5
Pa4
B4
A4
Pa3
A3
P3 B2
B3
A2 Pa2
B1
3 7 4 8 D
A1 Pa1
20
21
B10
11 2 4 MRV1
3
1
2 4
2 Pb8 Dr1 B9
B8 Pa8
B7
A7 Pa7
P1
Pa6
P2
A6
B6
Pa5
A5
B5
Pa4
B4
A4
Pa3
A3
P3 B2
B3
2 4 MRV1
18
17
26
201
MRV3
201
203
18
204
17
26
201
MRV3 204
203 204
P
P
T
204
T T
P
204
14
204
2 Pb8
T2
Pb6
Pb7
Pb5
Pb4
T1
Pb3
Pb2
P
P Pb10
Pb1
Pb8
T2
Pb6
Pb7
Pb5
Pb4
T1
Pb3
3
4
1
2
A1G A1
R1
A2 A2G A4
Ps
404
A3
9
4
Ps
4
404 405
406
T1,T2
T1,T2
13
P2
401
406
405
5
P2
401
DB
T1
19
P1
T1,T2
T1,T2 P2
406
405
7
403
401
P2
R2 A
B
8
10
19
402 P1
301
P1
7
403
30
303 305
D
A
R1
A
M
29
304
303 SH
305
D B D GH
29
B
8
10
305 B
304 R2
C PG
15
S1
304
SH
A C F E
302
304
S1
3
24 402 403
15
DB
23
P1
P
30
22
5
P2
6
301
P1
B D GH
406
13-1
402
403
404 405
T1
24 402
404
A3
401
302
P1
A
12
9
4
Ps
1
6
13-1
A2 A2G A4
Ps
13
3
23
A1G A1
R1
A1
A2
22
1
29
3
4
1
DOZER CIRCUIT - DOZER-DOWN OPERATION 4
P2
T
Pb1
12
SWING CIRCUIT - BOOM SWING-LEFT OPERATION
P
Pb2
Pp1
2
A1
T
204
T
Pp1
A2
P
T
204
14
2 P
Pb10
11
3
1
202
204
T
2 4
204
204 P
3
1
MRV2
202 201
D
A1 Pa1
11
MRV2
203
B1
206
204 203
A2 Pa2
3 7 4 8
11
3
1
Pa10
20
3 7 4 8
206
A10
R1
305
C
A C F E
PG
B
A
M
29 A
B
B
28
28 27
O
27
O
S A2B2 A1 B1
S A2B2 A1 B1 S
S
PP
PP P2 P SW31
P2 P SW31
P1 P SW30
25
P1 P SW30
25
16
16 3 7 4 8
3 7 4 8
21
B10
A10
Pa10
2 Pb8 Dr1 B9
B8 Pa8
B7
A7 Pa7
P1
P2
Pa6
A6
B6
Pa5
A5
B5
Pa4
A4
B4
Pa3
A3
P3 B2
B3
A2 Pa2
B1
D
A1 Pa1
20
21
B10
11 2 4 MRV1
3
1
2 4
3
1
Pa10
2 Pb8 Dr1 B9
B8 Pa8
B7
A7 Pa7
P1
P2
Pa6
A6
B6
Pa5
A5
B5
Pa4
A4
B4
Pa3
A3
P3 B2
B3
201
203
26
2 4
206
MRV2
MRV1
MRV3
201
203
18
204
17
26
201
P
T
MRV3
204
T P
204
2 T2
Pb8
Pb7
Pb6
Pb5
Pb4
Pb3
T1
Pb2
T
14
P
P Pb10
Pb1
T2
Pb8
Pb6
Pb7
Pb5
Pb4
Pb3
T1
8. 9. 10. 11. 12. 13. 14.
SWING CYLINDER DOZER CYLINDER SWIVEL JOINT PILOT VALVE (ATT) PILOT VALVE (TRAVEL) SOLENOID VALVE PILOT VALVE (DOZER)
15. 16. 17. 18. 19. 20. 21.
COMPONENT IDENTIFICATION SHUTTLE VALVE 22. NIBBLER CYLINDER MULTI CONTROL VALVE 23. STOP VALVE RETURN FILTER (ELEMENT) 24. SELECTOR VALVE SUCTION STRAINER 25. OIL COOLER INLINE FILTER 26. HYDRAULIC OIL TANK CHECK VALVE 27. SOLENOID VALVE HYDRAULIC RESERVOIR VENT 28. SOLENOID VALVE
29. ORIFICE
Pb2
T
Pb1
Pp1
2
PUMP ASSEMBLY CONTROL VALVE SLEWING MOTOR TRAVEL MOTOR BOOM CYLINDER / CANOPY CAB ARM CYLINDER BUCKET CYLINDER
T
204
T
Pp1
1. 2. 3. 4. 5. 6. 7.
P
T
204
2 P
Pb10
11
204 P
204
14
3
1
204
203
204
T
2 4
202
204 P
3
1
MRV2
204
201
203
D
A1 Pa1
11
11
202
17
B1
3 7 4 8
204
18
A2 Pa2
20
3 7 4 8
206
A10
1
4
3
2
12
1. 2. 3. 4. 5. 6.
NOTES 201 (MAIN RELIEF VALVE P1,P2) 23.0 MPa (3340 psi) 202 (MAIN RELIEF VALVE P3) 23.0 MPa (3340 psi) 203 (OVERLOAD RELIEF VALVE) 27.5 MPa (4000 psi) 204 (OVERLOAD RELIEF VALVE) 25.5 MPa (3700 psi) 304 (SLEW RELIEF VALVE) 18.5 MPa (2680 psi) 13-1 (PILOT RELIEF VALVE) 3.5MPa (508 psi)
1
4
3
12
HYDRAULIC SYMBOLS PRESSURE PILOT MAIN PRESSURE PILOT SEC PRESSURE CASE DRAIN COMPONENT
CHECK VALVE
54 COMPONENT NUMBER
SHOWS CIRCUIT CROSSING NOT CONNECTED
SHOWS CIRCUIT CONNECTED
FILTER OR SCREEN
HYDRAULIC SCHEMATIC EH27.B HYDRAULIC EXCAVATORS Additional copies of this Hydraulic and Electrical Schematic can be ordered through Technical Publications Distribution System. The part number is 6-78330
RESTRICTOR
OIL COOLER BC04N065
NIBBLER AND BREAKER CIRCUIT - NIBBLER CLOSE OPERATION
COMBINED OPERATION CIRCUIT - TRAVEL FORWARD, 1ST SPEED / DOZER-DOWN OPERATION 4
A1G A1
R1
A1
A2
A2 A2G A4
Ps
404
A3
9
4
Ps
4
404 405
406
T1,T2
T1,T2
13
P2
401
406
405
5
P2
401
DB
1 T1
P2
19
P1
7
403
30
B
8
P2
303
D
19
402 P1
301
P1
7
403
30
B
304 R2
A
A
M
29
303 305
R1
305
C
A C F E
PG
B
A
M
29 A
B
28
304
SH D
B D GH
29
B
8
10
305 PG
15
S1
C
A C F E
302
R1
305
3
24 402
304
SH
DB
23
304 R2
10
A
401
403
15 A
22
5
P2
P1
P
S1
29
405
6
301
P1
B D GH
P2
406
13-1
402
403
T1,T2
T1,T2
T1
24 402
406
1 302
P1
P
404 405
401
6
13-1
404
A3
A2 A2G A4
9
4
Ps
13
3
23
A1G A1
R1
A1
A2
22
Ps
B
28 27
O
27
O
S A2B2 A1 B1
S A2B2 A1 B1
S
S PP P2 P SW31
PP P2 P SW31
P1 P SW30
25
P1 P SW30
25
16
16
3 7 4 8
21
B10
A10
Pa10
2 Pb8 Dr1 B9
B8 Pa8
B7
A7 Pa7
P1
Pa6
P2
A6
B6
Pa5
A5
B5
Pa4
B4
A4
Pa3
A3
P3 B2
B3
A2 Pa2
B1
3 7 4 8 D
A1 Pa1
20
21
B10
11 2 4 MRV1
3
1
2 4
B8 Pa8
B7
A7 Pa7
P1
P2
Pa6
A6
B6
Pa5
A5
B5
Pa4
Pa3
B4
A4
A3
P3 B2
B3
2 4 MRV1
18
17
26
201
MRV3
201
203
18
204
17
P
T
26
201
MRV3 204
203
204
T P
204
2 Pb8
T2
Pb6
Pb7
Pb5
Pb4
T1
Pb3
Pb2
T
P
P Pb8
T2
Pb10
Pb1
Pb6
Pb7
Pb5
Pb4
T1
Pb3
Pb2
3
4
1
2
12
COMBINED OPERATION CIRCUIT - TRAVEL FORWARD, 1ST SPEED / BOOM-UP OPERATION
A1G A1
R1
A1
A2 A2G A4
404
TRAVEL PILOT VALVE
404 405
406
T1,T2
T1,T2 P2
401
406
405
H
302
P1
C
B A
402 P1
403
7
403
B
30
15
Pb8 R2
A
B
8
10
304
303 SH
305
D B D GH
Pb7 R1
B
4 P 1
(5)
3
B
(4)
Pb6
2
4 P 1
(6)
T
3
(1)
2
(2)
BUCKET DUMP
Pb5
T
Pb4
28 (3)
(7)
27
O
Pb3 (J / D MULTI) CONTROL VALVE
S A2B2 A1 B1
ARM
P2 P SW31
P1 P SW30
PG
25
P SW31 P1 P2
P SW30
SH B M DB A
16 3 7 4 8 B10
A10
Pa10
2 Pb8 Dr1 B9
B8 Pa8
B7
A7 Pa7
P1
P2
Pa6
A6
B6
Pa5
A5
B5
Pa4
A4
B4
Pa3
A3
P3 B2
B3
A2 Pa2
B1
(8) (4) (7) (3)
SLEWING MOTOR
PP
20
B1 A1 B2 A2
T D
A1 Pa1
PP
ARM OUT BOOM DOWN ARM IN BOOM UP
MRV1
B7
A7
H
H A6
ARM CYLINDER Pa5
A5
STOP VALVE
Pa4
A4
NIBBLR
P3
B2
Pb1
DOZER
B1
SELECTOR VALVE A2 A1
R
BREAKER NIBBLR
H
BREAKER
Pa3
A3
SLEW
R
Pa6
B3 T1
R
SWING CYLINDER
Pa7
P2
NIBBLR CYLINEDR
RETURN FILTER HYDRAULIC OIL TANK CHECK VALVE
Pa2 Pa1
CONTROL VALVE
BOOM SWING LEFT SLEW LEFT BOOM SWING RIGHT SLEW RIGHT
SOLENOID VALVE
SLEW RIGHT
SUCTION STRAINER
3
1
2 4
3
1
11
MRV2
IN
202 201
203
26
201
A3
MRV3
P
P
T
T
ENGINE
S
204
DOZER CYLINDER
204
2
P T2
A1
DOZER PILOT VALVE
FILTER
A2
E F C A
Pb10
OUT
HYDRAULIC PUMP
204
14
A4
204
203 204
T
BOOM CYLINDER
Pa8
T2
Pb2
204
P
Pb8'
SLEW LEFT 2 4
206
17
Pa10
R
3 7 4 8
11
18
A10
Dr1
TRAVEL B6 RIGHT SWING B5 B4 SERVICE
Pp1
S
21
BOOM TRAVEL LEFT
B8
P1
A
M
29 A
B9
ATT PILOT VALVE (R.H.) (8)
PG
BOOM
BUCKET DIGGING
ATT PILOT VALVE (L.H.)
305
C
A C F E
A
304
S1
B10
Pb10 BUCKET
301
P1
R
H
SHUTTLE VALVE
D
24 402
29
12
BUCKET CYLINDER
T
P
6
13-1
P
3
23
1
19
3
4 2
DB
T
401
3 1
SOLENOID VALVE (N&B)
22
5
P2
T1
P2
4
(LEFT) (RIGHT)
9
4
Ps
13
P
1
SCHEMATIC PIPING FOR HYDRAULIC SYSTEM Ps
A3
T
Pb1
Pp1
2
A2
T
204
T
Pp1
4
P
T
204
14
2 P
Pb10
11
204 P
204
14
3
1
202
204
T
2 4
204
204 P
3
1
MRV2
202 201
D
A1 Pa1
11
MRV2
203
B1
206
204 203
A2 Pa2
3 7 4 8
11
3
1
Pb8 Dr1 B9
20
3 7 4 8
206
2
Pa10
A10
Pb8
Pb7
Pb6
Pb5
Pb4
Pb3
T1
Pb2
H
G
OIL COOLER
B D SWIVEL JOINT
RELIEF VALVE
P1
T
P2
P 2
T
Pb1
R
H
1
UP
A1
DOWN Pp1
A2 2
1
4
3
SOLENOID VALVE
PILOT CIRCUIT T1 P1
12
P2
FORWARD P
BACKWARD
FORWARD BACKWARD
T2 P2
TRAVEL 2-SPEED T1
LEVER LOCK
MAIN CIRCUIT
P1 SUPPLY / RETURN (DRAIN) CIRCUIT
TRAVEL MOTOR (LEFT)
1. 2. 3. 4. 5. 6. 7.
PUMP ASSEMBLY CONTROL VALVE SLEWING MOTOR TRAVEL MOTOR BOOM CYLINDER / CANOPY CAB ARM CYLINDER BUCKET CYLINDER
8. 9. 10. 11. 12. 13. 14.
SWING CYLINDER DOZER CYLINDER SWIVEL JOINT PILOT VALVE (ATT) PILOT VALVE (TRAVEL) SOLENOID VALVE PILOT VALVE (DOZER)
15. 16. 17. 18. 19. 20. 21.
COMPONENT IDENTIFICATION SHUTTLE VALVE 22. NIBBLER CYLINDER MULTI CONTROL VALVE 23. STOP VALVE RETURN FILTER (ELEMENT) 24. SELECTOR VALVE SUCTION STRAINER 25. OIL COOLER INLINE FILTER 26. HYDRAULIC OIL TANK CHECK VALVE 27. SOLENOID VALVE HYDRAULIC RESERVOIR VENT 28. SOLENOID VALVE
29. ORIFICE
1. 2. 3. 4. 5. 6.
NOTES 201 (MAIN RELIEF VALVE P1,P2) 23.0 MPa (3340 psi) 202 (MAIN RELIEF VALVE P3) 23.0 MPa (3340 psi) 203 (OVERLOAD RELIEF VALVE) 27.5 MPa (4000 psi) 204 (OVERLOAD RELIEF VALVE) 25.5 MPa (3700 psi) 304 (SLEW RELIEF VALVE) 18.5 MPa (2680 psi) 13-1 (PILOT RELIEF VALVE) 3.5MPa (508 psi)
TRAVEL MOTOR (RIGHT)
HYDRAULIC SYMBOLS PRESSURE PILOT MAIN PRESSURE PILOT SEC PRESSURE CASE DRAIN COMPONENT
CHECK VALVE
54 COMPONENT NUMBER
SHOWS CIRCUIT CROSSING NOT CONNECTED
SHOWS CIRCUIT CONNECTED
FILTER OR SCREEN
HYDRAULIC SCHEMATIC EH27.B HYDRAULIC EXCAVATORS Additional copies of this Hydraulic and Electrical Schematic can be ordered through Technical Publications Distribution System. The part number is 6-78330
RESTRICTOR
OIL COOLER BC04N066