Hitachi ZAXIS 70 - Check Tightening Torque of Bolts and Nuts

MAINTENANCE
7-77
Check Tightening Torque of Bolts and Nuts
--- every 250 hours (first time after 50 hours)
Check tightness after the first 50 hours then every 250
hours. Tighten to torque shown if any are loose. Bolts and
nuts should be replaced with those of the same or higher
grade.
For tightening nuts and bolts other than specified in the ta-
ble below, refer to the Tightening Torque Chart at the end
of this section.
IMPORTANT: Check and tighten bolts and nuts using
a torque wrench.
Bolt Dia Torque
No. Descriptions
mm
Q’ty
Wrench
Size (mm)
N
x
m (kgf
x
m) (lbf
x
ft)
1 Engine cushion rubber mounting bolt 16 4 24 270 (27.5) 200
70, 70LC, 80SB, 80SBLC, 80LCK
14 8 22 140 (14.3) 200 2 Engine bracket
mounting bolt
85US
14 6 22 140 (14.3) 103
3 Hydraulic oil tank mounting bolt 16 4 24 210 (21.5) 155
4 Fuel tank mounting bolt 16 4 24
210 (21.5) 155
5 ORS fittings for hydraulic hoses and piping
17
19
22
27
32
36
41
25.0
29.5
39
93
137
175
205
(2)
(3)
(4)
(9.5)
(14)
(18)
(21)
15
22
29
69
101
129
151
6 Pump mounting bolt 12 4 19 90 (9.2) 66
7 Control valve mounting bolt 14 3 22 180 (18.4) 133
70, 70LC, 80SB, 80SBLC, 80LCK
12 4 19 90 (9.2) 66 8 Control valve bracket
mounting bolt
85US
14 4 22 140 (14.3) 103
9 Swing device mounting bolt 16 10 24 210 (21.5) 155
10 Swing motor mounting bolt 14 8 12 175 (18) 129
11 Battery mounting nut 10 4 17 20 (2.0) 15.0
12 Cab mounting nut 16 4 24 210 (21.5) 155
70, 70LC, 80SB, 80SBLC, 85US
16 24 24 210 (21.5) 155 Swing bearing mounting
bolt to upperstructure
80LCK
16 22 24 270 (27.5) 200
13
Swing bearing mounting bolt to undercarriage 16 24 24 270 (27.5) 200
Travel device mounting bolt 16 20 24 300 (31) 220
14
Travel reduction device cover mounting bolt 14 8 22 140 (14.3) 103
15 Sprocket mounting bolt 16 24 24 270 (27.5) 200
16 Upper roller mounting bolt 14 2 22 140 (14.3) 103
17 Lower roller mounting bolt 14 40 22 245 (25) 180
70, 80SB 14 304 22 245 (25) 180
18 Track shoe bolt
70LC, 80SBLC 80LCK,85US 14 320 22 245 (25) 180
19 Cover mounting bolt
6
10
12
10
17
19
10
50
90
1
5.1
9.2
7.4
37
66
20 Coupling and T-bolt clamp of low pressure piping
8 －
－
－
13
11
9.5
10.3 to 12.4
6.0
4.4
(1.05 to 1.26)
(0.6)
(0.45)
(7.6 to 9.1)
(4.4)
(3.3)
21 Side-cutter mounting bolt 20 6 30 540 55 (400)
19