42. Thread Repair

- TOOLS REQUIRED
- J42385-850 Thread Repair Kit

The Time Sert (R) thread repair process involves a solid bushing type insert. The insert is made of carbon and is self-locking. During the bushing installation process, the driver tool expands the bottom external threads of the insert into the base material. 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 counter-bore of the repaired hole.

CAUTION: WEAR SAFETY GLASSES IN ORDER TO AVOID EYE DAMAGE.

IMPORTANT: The use of a cutting type fluid GM P/N 1052864, WD 40 (R), or equivalent is recommended when performing drilling, counter-boring, and tapping procedures.

Driver oil must be used on installer driver tool.
The tool kits are designed for use with either a suitable tap wrench or drill motor.

1. Drill out threads of damaged hole.
2. Using compressed air, clean out any chips.

3. Counter-bore hole to full depth permitted by tool.
4. Using compressed air, clean out any chips.

5. Using a tap wrench, tap threads of drilled hole.
6. Using compressed air, clean out any chips.
7. Spray cleaner GM P/N 12346139, P/N 12377981 or equivalent into holes.
8. Using compressed air, clean any cutting oil and chips out of drilled hole.

IMPORTANT: Do not allow oil or other foreign material to contact outside diameter (OD) of insert.

9. Lubricate threads of installer tool with drive oil.

10. Install insert onto installer tool.

11. Apply threadlock Loctite (R) 277, J-42385-109 or equivalent to insert OD threads.

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

12. Install insert into hole.
a. Install insert until flange of insert contacts counter-bored surface.
b. Continue to rotate installer tool through insert.

IMPORTANT: A properly installed insert will be either flush or slightly below flush with surface of base material.

13. Inspect insert for proper installation into hole.

CYLINDER HEAD BOLT HOLE THREAD REPAIR PROCEDURE

- TOOLS REQUIRED
- J42385-850 Thread Repair Kit

The cylinder head bolt thread repair kit consists of the following items:
- Drill (1)
- Tap (2)
- Installer (3)
- Alignment Pin (4)
- Bushing (5)
- Bolts (6)
- Fixture Plate (7)

CAUTION: WEAR SAFETY GLASSES IN ORDER TO AVOID EYE DAMAGE.

IMPORTANT: The use of a cutting type fluid GM P/N 1052864, WD 40(R), or equivalent is recommended when performing drilling, counter-boring, and tapping procedures.

Driver oil must be used on installer driver tool.
The tool kits are designed for use with either a suitable tap wrench or drill motor.

1. Install fixture plate, bolts, and bushing onto engine block deck.
2. Position fixture plate and bushing over hole that is to be repaired.

3. Position alignment pin through bushing and into hole.
4. With alignment pin in desired hole, tighten fixture retaining bolts.
5. Remove alignment pin from hole.

IMPORTANT: During drilling process, it is necessary to repeatedly remove drill and clean chips from hole.

6. Drill out threads of damaged hole.
7. Using compressed air, clean out any chips.

8. Using tap wrench, tap threads of drilled hole.

9. Tap new threads to proper depth by turning tap into hole until mark on tap aligns with top of drill bushing.
10. Remove fixture plate, bushing, and bolts.
11. Using compressed air, clean out any chips.
12. Spray cleaner GM P/N 12346139, P/N 12377981, or equivalent into hole.
13. Using compressed air, clean any cutting oil and chips. Out of hole.

IMPORTANT: Do not allow oil or other foreign material to contact outside diameter (OD) of insert.

14. Lubricate threads of installer tool with driver oil.

15. Install insert onto driver tool.

16. Apply threadlock Loctite (R) 277, J 42385-109, or equivalent to insert OD threads.

17. Install insert and driver into hole.

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

18. Rotate driver tool until mark on tool aligns with deck surface of engine block.

MAIN CAP BOLT HOLE THREAD REPAIR PROCEDURE

- TOOLS REQUIRED
- J42385-850 Thread Repair Kit

The cylinder head bolt thread repair kit consists of the following items:
- Drill (1)
- Tap (2)
- Installer (3)
- Alignment Pin (4)
- Bushing (5)
- Bolts (6)
- Fixture Plate (7)

IMPORTANT: Position fixture plate and bushing over hole that is to be repaired.

1. Install fixture plate, bolt, and bushing, onto engine block.
2. Position alignment pin in desired hole and tighten fixture retaining bolts.

IMPORTANT: Drill until stop collar of drill bit contacts the bushing.

3. Drill out damaged hole.
4. Using compressed air, clean out any chips.

IMPORTANT: Tap the new threads to proper depth by turning tap into hole until mark on tap aligns with top of bushing.

5. Using a tap wrench, tap threads of drilled hole.
6. Using compressed air, clean out any chips.
7. Spray cleaner GM P/N 12346139, or equivalent into hole.
8. Using compressed air, clean any cutting oil and chips out of hole.

IMPORTANT: Do not allow oil or other foreign material to contact outside diameter (OD) of insert.

9. Lubricate threads of installer tool with driver oil.

10. Install insert onto driver tool.

11. Apply threadlock Loctite (R) 277, J 42385-109, or equivalent to insert OD threads.

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