Isuzu — Repair Procedure

A Isuzu service procedure — check it applies to your exact model before use.

Procedure

23.0}
*M16 × 2
100.0 — 149.1 {10.2 —
15.2}
109.4 — 164.2 {11.2 —
16.7}
129.4 — 194.2 {13.2 —
19.8}
142.5 — 213.8 {14.5 —
21.8}
M18 × 1.5
151.0 — 225.6 {15.4 —
23.0}
—
195.2 — 293.2 {19.9 —
29.9}
—
*M18 × 2.5
151.0 — 225.6 {15.4 —
23.0}
—
196.1 — 294.2 {20.0 —
30.0}
—
M20 × 1.5
206.0 — 310.0 {21.0 —
31.6}
—
269.7 — 405.0 {27.5 —
41.3}
—
*M20 × 2.5
190.2 — 286.4 {19.4 —
29.2}
—
249.1 — 374.6 {25.4 —
38.2}
—
M22 × 1.5
251.1 — 413.8 {25.6 —
42.2}
—
362.8 — 544.3 {37.0 —
55.5}
—
*M22 × 2.5
217.7 — 327.5 {22.2 —
33.4}
—
338.3 — 507.0 {34.5 —
51.7}
—
M24 × 2
358.9 — 539.4 {36.6 —
55.0}
—
430.5 — 711.0 {43.9 —
72.5}
—
*M24 × 3
338.3 — 507.0 {34.5 —
51.7}
—
406.0 — 608.0 {41.4 —
62.0}
—
General Information 0A-11
The * mark indicates where soft materials have been used for internal thread sections, such as castings.
N⋅m {kgf⋅m}
Strength classifica-
tion
8.8
9.8
9T
Shape of bolt head
Hexagon head bolt
Flange bolt
Hexagon head bolt
Flange bolt
M6 × 1
5.6 — 11.2 {0.6 — 1.1}
6.6 — 12.2 {0.6 — 1.2}
—
—
M8 × 1.25
13.4 — 25.7 {1.4 — 2.6}
15.3 — 28.4 {1.6 — 2.9}
16.7 — 30.4 {1.7 — 3.1}
18.1 — 33.6 {1.9 — 3.4}
M10 × 1.25
31.3 — 52.5 {3.2 — 5.4}
35.4 — 58.9 {3.6 — 6.1}
37.3 — 62.8 {3.8 — 6.4}
42.3 — 70.5 {4.3 — 7.2}
*M10 × 1.5
31.3 — 51.4 {3.2 — 5.2}
34.5 — 57.5 {3.5 — 5.8}
36.3 — 59.8 {3.7 — 6.1}
40.1 — 66.9 {4.1 — 6.8}
M12 × 1.25
69.3 — 104.0 {7.1 —
10.6}
77.7 — 116.5 {7.9 —
11.9}
75.5 — 113.8 {7.7 —
11.6}
85.0 — 127.5 {8.7 —
13.0}
*M12 × 1.75
64.8 — 96.1 {6.6 — 9.8}
71.4 — 107.2 {7.3 —
10.9}
71.6 — 106.9 {7.3 —
10.9}
79.5 — 119.2 {8.1 —
12.2}
M14 × 1.5
106.2 — 158.8 {10.8 —
16.2}
114.9 — 172.3 {11.7 —
17.6}
113.8 — 170.6 {11.6 —
17.4}
123.4 — 185.1 {12.6 —
18.9}
*M14 × 2
100.6 — 149.8 {10.3 —
15.3}
108.2 — 162.2 {11.1 —
16.6}
106.9 — 160.0 {10.9 —
16.3}
115.5 — 173.3 {11.8 —
17.7}
M16 × 1.5
154.3 — 232.5 {15.7 —
23.7}
171.1 — 256.7 {17.4 —
26.2}
160.0 — 240.3 {16.3 —
24.5}
176.9 — 265.3 {18.0 —
27.1}
*M16 × 2
147.6 — 221.4 {15.0 —
22.6}
162.5 — 243.8 {16.6 —
24.9}
153.0 — 229.5 {15.6 —
23.4}
168.5 — 252.7 {17.2 —
25.8}
M18 × 1.5
222.5 — 334.3 {22.7 —
34.1}
—
229.5 — 345.2 {23.4 —
35.2}
—
*M18 × 2.5
223.6 — 335.4 {22.8 —
34.2}
—
230.5 — 346.2 {23.6 —
35.3}
—
M20 × 1.5
307.4 — 461.7 {31.4 —
47.1}
—
316.8 — 475.6 {32.3 —
48.5}
—
*M20 × 2.5
284.0 — 472.1 {29.0 —
43.5}
—
293.2 — 440.3 {29.2 —
44.9}
—
M22 × 1.5
413.6 — 620.5 {42.2 —
63.3}
—
424.6 — 636.5 {43.3 —
64.9}
—
*M22 × 2.5
385.7 — 578.0 {39.3 —
58.9}
—
394.2 — 592.3 {40.0 —
60.4}
—
M24 × 2
490.8 — 810.5 {50.0 —
82.7}
—
554.1 — 830.6 {56.5 —
84.7}
—
*M24 × 3
462.8 — 693.1 {47.2 —
70.7}
—
520.7 — 781.6 {53.1 —
79.7}
—
0A-12 General Information
Designations for Isuzu standard bolt heads
Name
1. Hexagon Head Bolt (4.8, 4T)
2. Hexagon Head Bolt (4.8, 4T)
3. Flange Bolt (4.8, 4T)
4. Flange Bolt (4.8, 4T)
5. Hexagon Head Bolt (7T)
6. Flange Bolt (7T)
7. Hexagon Head Bolt (Thermal Refined 8.8)
8. Hexagon Head Bolt (Thermal Refined 8.8)
9. Hexagon Head Bolt (Nonthermal Refined 8.8)
10. Hexagon Head Bolt (Nonthermal Refined 8.8)
11. Flange Bolt (8.8)
12. Flange Bolt (8.8)
13. Hexagon Head Bolt (9.8, 9T)
14. Hexagon Head Bolt (9.8, 9T)
15. Flange Bolt (9.8, 9T)
16. Flange Bolt (9.8, 9T)
Flare nut
Pipe diameter
Tightening torque
(for medium and large size
vehicles)
Width across flats of flare nut
(mm)
Old
New
Flare nut tightening torque
(service standard value) N⋅m {kgf⋅m}
φ 4.76 mm
12.8 — 18.6 {1.3 — 1.9}
14
14
φ 6.35 mm
23.5 — 49 {2.4 — 5.0}
17
17
φ 8.0 mm
23.5 — 49 {2.4 — 5.0}
19
17
φ 10.0 mm
44.1 — 93.2 {4.5 — 9.5}
22
19
φ 12.0 mm
58.8 — 137.3 {6.0 — 14.0}
27
24
φ 15.0 mm
78.5 — 156.9 {8.0 — 16.0}
30
30
General Information 0A-13
Taper screw from connectors (brass)
About angle method tightening
Though the general and current way to tighten bolts
and nuts is torque indication, using this way results in
large unevenness of shaft power to indicated torque.
Therefore, bolts may be damaged at upper limit when
you try to ensure minimal shaft power.
To ensure shaft power with small unevenness, it is nec-
essary to tighten bolts measuring stretch amount of
bolts, but this is actually impossible. So the angle
method focuses on screw pitch as equivalent to bolt
stretch, and controls using the screw rotation amount.
The method can reduce the unevenness of shaft power
by tightening to plastic range.
How to tighten
1. Apply molybdenum disulfide or engine oil to the
threads and the seating surface of the bolt follow-
ing the instruction.
2. Tighten all bolts to the pre-indicated tightening
torque.
3. Draw lines on the surface of the parts you tighten:
the lines which pass through the bolt’s center (A —
B: bolt side) (C — D: parts side) and the line at the
specified tightening angle from the bolt’s center (E
— F).
Name
1. Specified Tightening Torque
4. Tighten the bolt with wrench until the line on the
bolt (A — B) aligns with the specified angle line (E
— F on the surface of the parts).
Be sure to check the mark to see whether you
tighten the bolt to the specified angle or not.
If you fail this, you may tighten the bolt by the
angle method again by accident and damage the
bolt. Take extreme care.
Important:
• Follow the instructed order to tighten bolts.
• Do not retighten if you tighten by the angle
method.
Bolt angle gauge (5-8840-0266-0), the tool for tighten-
ing bolts by the angle method, is set.
Special tool classification
A; Essential tool
Servicing operation cannot be done with any other
tools than the essential tool.
B; Recommend tool
Servicing work can be done with a general-purpose
tool commercially available. However, it is advisable to
use the recommended tool as much as possible for a
reduced work time and an improved safety in work
operations.
C; Available tool
Although it takes a more working time, servicing opera-
tions can be made with a tool commercially available as
substitute for the available tool.
N⋅m {kgf⋅m}
Screw size
PT (R) 1/8
PT (R) 1/4
PT (R) 3/8
PT (R) 1/12
—
2.0 — 14.7
{0.2 — 1.5}
4.9 — 15.7
{0.5 — 1.6}
9.8 — 16.7
{1.0 — 1.7}
9.8 — 17.7
{1.0 — 1.8}
E
F
D
C
B
A
1
WSLE0008
A
B
C
D
E
F
WSLE0009
0A-14 General Information
Recommended Lubricant
Engine oil
Use the engine oil below.
Engine oil grade
* mark may vary depending on each machine. Refer to the machine manufacturer specification.
ISUZU genuine engine oil
Besco Super: CC
Besco S — 3: CD
Besco Multi Z: CD
Engine oil viscosity chart
The engine oil affects the startability, driving performance, oil consumption, wear of the sliding part, and seizure,
depending on the viscosity. You should select the engine oil depending to a temperature and the chart above.
Engine oil level
4LE2X model: Approx. 9.3 — 12.1 L {9.8 — 12.8 qts}
4LE2N model: Approx. 5.9 — 8.4 L {6.2 — 8.9 qts}
Note:
Engine oil level may vary depending on the machine specification.
Engine classification
Engine oil grade (API service category)
With turbocharger
CD or CF-4
* (CE, CF, CH-4, CI-4 or CI-4 Plus)
ENGINE OIL VISCOSITY GRADE – AMBI

Source: manual:SM-JCB-Isuzu-Engine-AU-4LE2-BV-4LE2-2.pdf. Figures and steps are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.