SECTION 3 HYDRAULIC SYSTEM
Group 1 Hydraulic Circuit 3-1
Group 2 Main Circuit 3-2
Group 3 Pilot Circuit 3-5
Group 4 Single Operation 3-13
Group 5 Combined Operation 3-23
GROUP 1 HYDRAULIC CIRCUIT
SECTION 3 HYDRAULIC SYSTEM
8
Last guard filter
1 Main pump
2 Main control valve
3 Swing motor
4 Travel motor
5 RCV lever(LH)
6 RCV lever(RH)
7 RCV pedal
8 Boom cylinder(LH)
9 Boom cylinder(RH)
10 Arm cylinder
11 Bucket cylinder
12 Turning joint
13 Check valve
14 Check valve
15 Hydraulic tank
16 Oil cooler
17 Air breather
18 Return filter
19
20
Strainer

P2
D2
P3
P1
D1
dr3
B
A
B
A
Pk
Pi1
V2
E
V2
Pi1
E
dr7
T(dr6)
T(dr5)
Bo
Ao
XBa2
XAa2
XAk
Ak1
Bk1
XBk
PbL
Dr4

Pns
Ck1
XAs
PaL
XBs
XAb2
XAa1
a4
a1
a2
B3
B1
a3
Psv
Pi2
(Fr,MCV)
Pi1
(Fl,MCV)
Pm2
Pm1
Dr
A2
A1
M
XAo
XBo
SH
JH
FGEDBA
XAa1

P2
P1
A4 A3
A2
A1
Pm2
(Pump)
Pm1
(Pump)
PG(MCV)
PG(S/Motor)
T(dr2)
Pk
(T/Joint)
Pz
(MCV)
Dr#,dr#
XBs
XAb2
XBa1
Ba1
Aa1
XAa1
(XBp2)
Dr1
Dr2
Dr3
Pns
Ck1
XBp1

13
14
15
19
17
21
23
22
25
26
6
7
5
34
12
4
3
26 RCV pedal
27 Boom cylinder(LH)
30 Safety lock valve
31 Safety lock valve
32 Pressure switch
33 Shutoff valve
34 Tilt bucket pedal
35 Accumulator
36 Accumulator
37 Stop valve
38 Port relief valve
39 Port relief valve
40