Isuzu KB P190. Manual — part 681

Engine Mechanical – V6

Page 6A1–245

1

It is critical the drilling, counter boring and tapping of
the hole to be repaired follows the same centreline (1)
as the original hole.

Figure 6A1 – 462

2

During the drilling and tapping of the hole being
repaired, ensure the tooling is consistently machining
perpendicular to the surface of the base material.

Figure 6A1 – 463

3

If the threaded hole being repaired has a base
surface perpendicular to the hole centreline, tapping
guides are available to aid in tapping the hole.

Tap

Size

Tap

Guide

Tap

Size

Tap

Guide

Tap

Size

Tap

Guide

- J

42385

- J

42385

- J

42385

6 x 1.0

729

10 x

1.5

731 14

x

1.5

736

8 x

1.25

730 12

x

1.5

732 20

x

1.5

737

Figure 6A1 – 464

Engine Mechanical – V6

Page 6A1–246

General Thread Repair

N O T E

The use of a cutting type fluid such as WD 40® or
equivalent is recommended when performing the
drilling, counter boring and tapping procedures

1

When installed to the correct depth, the flange (1) of
the insert will be seated against the counter bore of
the drilled/tapped hole and just below the surface (2)
of the base material.

Figure 6A1 – 465

N O T E

During the drilling process, repeatedly remove
the drill and clean the swarf from the hole and
the flutes of the drill.

CAUTION

Do not drill any further than the original hole
depth.

2

Drill out the threads of the damaged hole to the
correct depth for the thread being repaired:
•

M6 inserts require a minimum drill depth of 15
mm.

•

M8 inserts require a minimum drill depth of 20
mm.

•

M10 inserts require a minimum drill depth of
23.5 mm.

Figure 6A1 – 466

N O T E

All swarf must be removed from the drilled hole
prior to tapping.

Safety glasses must be worn when using
compressed air.

3

Using compressed air, clean out any swarf.

Figure 6A1 – 467

Engine Mechanical – V6

Page 6A1–247

N O T E

A correctly counter bored hole will show a slight
burnishing on the surface of the base material
for 360 degrees around the drilled hole.

4

Counter bore the drilled hole to the full depth
permitted by the tool (1).

Figure 6A1 – 468

N O T E

All swarf must be removed from the drilled hole
prior to tapping.

Safety glasses must be worn when using
compressed air.

5

Using compressed air, clean out any swarf.

Figure 6A1 – 469

N O T E

• During the tapping process, repeatedly

remove the tap and clean the swarf from the
hole and the flutes of the tap.

• Ensure the tap has created full threads at

least to the depth equal to the insert length.

6

Using a suitable tapping wrench, tap the threads of
the drilled hole by hand only.
•

M6 inserts require a minimum drill depth of 15
mm.

•

M8 inserts require a minimum drill depth of 20
mm.

•

M10 inserts require a minimum drill depth of
23.5 mm.

Figure 6A1 – 470

Engine Mechanical – V6

Page 6A1–248

N O T E

All swarf must be removed from the tapped hole
prior to insert installation.

Safety glasses must be worn when using
compressed air.

7

Using compressed air, clean out any swarf.

Figure 6A1 – 471

8

Spray a commercially available thread cleaner into
the tapped hole.

Figure 6A1 – 472

N O T E

All swarf must be removed from the tapped hole
prior to insert installation.

Safety glasses must be worn when using
compressed air.

9

Using compressed air, clean out any swarf.

Figure 6A1 – 473