Standard Thread Repair - Flush Hole

Fig 1: View Of Bushing Type Insert & Base Material

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

Fig 2: Drilling Out Threads Of Damaged Hole
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IMPORTANT:
• During the drilling process, it is necessary to repeatedly remove the drill and clean chips from the hole and the flutes of the drill.
• Do NOT drill any further than the original hole depth.
1. Drill out the threads of the damaged hole.
   • 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).
Fig 3: Cleaning Out Metal Chips
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IMPORTANT: All chips must be removed from the drilled hole prior to tapping.
2. Using compressed air, clean out any chips.
Fig 4: View Of Counterbore Drill
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IMPORTANT: A properly counterbored hole will show a slight burnishing on the surface of the base material for 360 degrees around the drilled hole.
3. Counterbore the drilled hole to the full depth permitted by the tool (1).
Fig 5: Cleaning Out Metal Chips
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IMPORTANT: All chips must be removed from the drilled hole prior to tapping.
4. Using compressed air, clean out any chips.
Fig 6: Tapping Threads Of Drilled Hole
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IMPORTANT:
• During the tapping process, it is necessary to repeatedly remove the tap and clean chips 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.
5. Using a suitable tapping wrench, tap the threads of the drilled hole.
   • 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).
Fig 7: Cleaning Out Metal Chips
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IMPORTANT: All chips must be removed from the tapped hole prior to insert installation.
6. Using compressed air, clean out any chips.
Fig 8: Spraying Cleaner Into Tapped Hole
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7. Spray cleaner GM P/N United States 12377981, GM P/N Canada 10953463 or equivalent into the tapped hole.
Fig 9: Cleaning Out Metal Chips
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IMPORTANT: All chips must be removed from the tapped hole prior to insert installation.
8. Using compressed air, clean out any chips.
Fig 10: Lubricating Installer Tool Using Driver Oil
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IMPORTANT: Do not allow oil or other foreign material to contact the outside diameter (OD) of the insert.
9. Lubricate the threads of the driver installation tool (2) with the driver oil (1) J 42385-110.
Fig 11: View of Bushing Type Insert
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10. Install the insert (2) onto the driver installation tool (1).
Fig 12: Applying Threadlock To Insert
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11. Apply threadlock sealant GM P/N United States 12345493, GM P/N Canada 10953488, J 42385-109, LOCTITE 277® or equivalent (1) to the insert OD threads (2).
Fig 13: Installing Insert Into Tapped Bolt Hole
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12. Install the insert (2) into the tapped hole.
Fig 14: Installing Insert - Standard Thread
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IMPORTANT: If the insert will not thread down until the flange contacts the counterbored surface, remove the insert immediately with a screw extracting tool and inspect the tapped hole for any remaining chips and/or improper tapping.
13. Install the insert until the flange (2) of the insert contacts the counterbored surface.
Fig 15: View Insert And Tool - Standard Thread
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IMPORTANT: The driver installation tool will tighten up before screwing completely through the insert. This is acceptable. The threads at the bottom of the insert are being formed and the insert is mechanically locking the insert into the base material threads.
14. Continue to rotate the driver installation tool (1) through the insert (2).
Fig 16: View Of Bushing Type Insert & Base Material
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15. Inspect the insert for proper installation into the tapped hole. A properly installed insert (1) will be either flush or slightly below flush with the surface of the base material (2).
Fig 17: View Of Restricted Engine Coolant Passages - Standard Thread Repair
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16. Any installed insert that restricts or blocks an oil or engine coolant passage (3) will need to have the oil or engine coolant passage drilled out (4) to the original size of the oil or engine coolant passage. After drilling the restriction or blockage, clean out any chips and thread the installation driver tool through the insert again to remove any burrs caused by the drilling of the oil or engine coolant passage.