General Thread Repair

WARNING: This page is about a different variant/trim than selected.

Fig 1: Identifying Thread Repair Inspection Area

Courtesy of SAAB-SCANIA OF AMERICA, INC.

The thread repair process involves a solid, thin walled, self-locking, carbon steel, bushing type insert (1). During the bushing installation process, the driver tool expands the bottom external threads of the insert into the base material (2). This action mechanically locks the insert in place. Also, when installed to the proper depth, the flange of the insert will be seated against the counterbore of the repaired hole.

NOTE: The use of a cutting fluid is recommended when performing the drilling, counterboring, and tapping procedures.
Driver oil MUST be used on the installer driver tool.
The tool kits are designed for use with either a suitable tap wrench or drill motor.

Refer to ADHESIVES, FLUIDS, LUBRICANTS, AND SEALERS (LDK, LHU) for recommended cutting fluid and driver oil.

Drill out the threads of the damaged hole (1).

Fig 2: Drilling Out Threads Of Damaged Hole
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- M6 inserts require a minimum drill depth of 15 mm (0.59 in).
- M8 inserts require a minimum drill depth of 20 mm (0.79 in).
- M10 inserts require a minimum drill depth of 23.5 mm (0.93 in).
Refer to SAFETY GLASSES AND COMPRESSED AIR WARNING .
Using compressed air, clean out any chips.
Counterbore the hole to the full depth permitted by the tool (1).

Fig 3: Drilling Hole To Full Depth Using Tool
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Using compressed air, clean out any chips.
Using a tap wrench (2), tap the threads of the drilled hole.

Fig 4: Tapping Threads Of Drilled Hole Using Tap Wrench
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- M6 inserts require a minimum tap depth of 15 mm (0.59 in).
- M8 inserts require a minimum tap depth of 20 mm (0.79 in).
- M10 inserts require a minimum tap depth of 23.5 mm (0.93 in).
Refer to SAFETY GLASSES AND COMPRESSED AIR WARNING .
Refer to CLEANING SOLVENT WARNING .

Using compressed air, clean out any chips.
Spray cleaner into the hole. Refer to ADHESIVES, FLUIDS, LUBRICANTS, AND SEALERS (LDK, LHU) .
Using compressed air, clean any cutting oil and chips out of the hole.
NOTE: Do not allow oil or other foreign material to contact the outside diameter (OD) of the insert.

Lubricate the threads of the installer tool (2) with the driver oil (1).

Fig 5: Lubricating Threads Of Installer Tool Using Driver Oil
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Install the insert (2) onto the driver tool (1).

Fig 6: Installing Insert Onto Driver Tool
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Apply threadlock LOCTITE™ 277, EN-43600-109 (1) loctite, or equivalent to the insert OD threads (2).

Fig 7: Applying Threadlock LOCTITE 277 To Insert OD Threads
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Install the insert (2) into the hole.
Install the insert until the flange of the insert contacts the counterbored surface. Continue to rotate the installer tool (1) through the insert.

The installer tool will tighten up before screwing completely through the insert. This is acceptable. You are forming the bottom threads of the insert and mechanically locking the insert to the base material threads.

Fig 8: Rotating Installer Tool Through Insert
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Inspect the insert for proper installation into the hole.
A properly installed insert (1) will be either flush or slightly below flush with the surface of the base material (2).

Fig 9: Identifying Base Material Surface
Courtesy of SAAB-SCANIA OF AMERICA, INC.