This 10-phase procedure uses the LS-8704 insert to repair stripped bolt holes on Cat 3406 engine blocks—restores strong, reliable threads for head bolts, liner bolts, or deck applications. Introduction: Reliable Thread Repair for Cat 3406 Blocks The LS-8704 insert provides full-strength repair—essential for maintaining head torque and gasket sealing without block replacement. Phase 1-3: Preparation & Damaged Hole Assessment Secure engine block – Fixture or stand support Remove head / components – Gain full access to hole Inspect & measure damaged threads – Confirm stripping extent Phase 4-6: Hole Preparation & Insert Installation Drill & tap to 7/8"-16 – Clean, straight, full depth Apply thread locker – High-strength compound on insert Install LS-8704 insert – Torque to spec with proper tool Phase 7-10: Finishing & Verification CRITICAL: LS-8704 Insert Protocol Trim excess insert length – If required, flush to deck Chase internal 3/4"-16 threads – Ensure clean & true Reassemble head / components – Torque to Cat specs Pressure test & run engine – Verify no leaks Critical Warnings: Thread Insert Installation Hazards AVOID THESE EXPENSIVE MISTAKES: ❌ Off-center drilling/tapping – Misaligned insert ❌ Insufficient depth – Weak thread engagement ❌ No thread locker – Insert backing out ❌ Over-torque insert – Block cracking ❌ Skip internal thread chase — Bolt binding Why LS-8704 Beats Other Repair Methods Alternative Risks: ❌ Heli-coil → $500–$2K failure risk ❌ Oversize bolt → Misalignment ❌ Block replacement → $8K–$18K cost LS-8704 Advantages: ✅ Full-length 3-1/4" engagement ✅ Standard 3/4"-16 bolt compatibility ✅ Strong, reliable repair ✅ Saves block & thousands ✅ Bulk pricing down to $32.48 ✅ Proven 3406 solution Restore Cat 3406 Bolt Holes Professionally. Strong Threads. Save Thousands. Keep Blocks Alive. Get LS-8704 – $56.00