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The LS-8704 Bolt Hole Thread Insert restores stripped or damaged threads in Caterpillar 3406 block decks. With inside 3/4" x 16 TPI and outside 7/8" x 16 TPI, this 3 1/4" insert ensures secure bolting for gasket sealing and engine integrity.

The Critical Risks of Stripped Bolt Holes in CAT 3406 Engines

Caterpillar 3406 engines power heavy-duty applications, but stripped block deck bolt holes lead to gasket failures, leaks, and breakdowns, escalating repair costs.

• Gasket blow-out – Loose bolts cause leaks, requiring $1,000–$2,500 head gasket jobs
• Fluid contamination – Coolant/oil mixing damages internals, costing $2,000–$4,000
• Compression loss – Weak threads reduce seal, leading to $1,500–$3,000 diagnostics
• Downtime losses – Repairs extend service 2–4 hours, adding $300–$600 labor
• Block damage – Severe stripping demands machining, totaling $1,500–$3,000
• Engine failure – Untreated issues require rebuilds ($5,000–$10,000)

What is the LS-8704 Bolt Hole Thread Insert?

The LS-8704 Caterpillar 3406 Bolt Hole Thread Insert is a precision repair insert for restoring stripped block deck threads. Inside 3/4" x 16 TPI, outside 7/8" x 16 TPI, length 3 1/4", it provides strong, secure bolting.

Ideal for diesel shops, the LS-8704 avoids block replacement, cuts repair time by 50%, and ensures reliable gasket sealing.

Complete Insert Specifications & CAT Compatibility

Professional Features & Engine Repair Benefits

Economic Impact: Bolt Hole Repair ROI

Scenario	Cost Impact
LS-8704 proper repair	Thread restore – $56 insert (bulk lower)
Gasket blow-out	$1,000–$2,500 jobs
Contamination damage	$2,000–$4,000
Compression diagnostics	$1,500–$3,000
Block machining	$1,500–$3,000
Total improper repair cost	$6,000–$12,500 per failure
LS-8704 ROI (first prevention)	107–223X return on investment

When CAT Technicians Choose LS-8704

• Caterpillar 3406 block deck repairs
• Stripped thread restoration
• Head gasket bolting
• Engine overhauls
• Bulk shop purchases
• Heavy-duty diesel maintenance
• Sealing optimization

Why Professional Shops Trust LS-8704

CAT rebuilders trust the LS-8704 for its precision threads, bulk pricing, and ability to avoid $6,000–$12,500 in damages per failure. It offers secure bolting, fast repairs, and reliability pros demand.

From stripped holes to full overhauls, this insert keeps CAT engines strong.

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