The ATC-8240 Upper Deck Insert restores worn or damaged counterbores in Caterpillar 3406 and C15 blocks. Replacement for PT-8240/5P4173, this precision insert ensures proper liner protrusion and sealing for reliable heavy-duty performance.

The Critical Risks of Damaged Upper Deck in CAT Engines

Caterpillar 3406 and C15 engines face intense demands, but pitted or cracked upper deck counterbores lead to liner misalignment, leaks, and failures. Without inserts, repairs escalate costs.

• Liner protrusion issues – Worn ledges cause blow-by, requiring $1,000–$2,500 gasket jobs
• Sealing failures – Cracks allow contamination, costing $2,000–$4,000 cleanups
• Compression loss – Misaligned liners reduce power, leading to $1,500–$3,000 diagnostics
• Downtime losses – Extended repairs add $300–$600/hour in fleet idle
• Block damage – Severe pitting demands machining, totaling $2,000–$4,000
• Engine overhaul – Cascading failures require rebuilds ($5,000–$10,000)

What is the ATC-8240 Upper Deck Insert?

The ATC-8240 / PT-8240 Caterpillar 3406 / C15 Block Deck / Upper Insert is a precision insert that restores the upper counterbore ledge. With OD 6.665″ and height 0.205″, it's a direct replacement for PT-8240/5P4173, providing stable liner seating.

Designed for professional rebuilders, the ATC-8240 avoids excessive machining, ensures concentric surfaces, and supports long-term engine durability.

Complete Insert Specifications & Caterpillar Compatibility

Professional Features & Engine Rebuild Benefits

Economic Impact: Block Repair ROI

Scenario	Cost Impact
ATC-8240 proper restoration	Sealing restore – $68.50 insert (bulk lower)
Blow-by gasket fail	$1,000–$2,500 replacements
Contamination cleanup	$2,000–$4,000
Power loss diagnostics	$1,500–$3,000
Engine rebuild	$5,000–$10,000
Total improper repair cost	$9,500–$19,500 per failure
ATC-8240 ROI (first prevention)	139–285X return on investment

When CAT Technicians Choose ATC-8240

• Caterpillar 3406 block deck repair
• C15 upper counterbore restoration
• Liner protrusion optimization
• PT-8240/5P4173 upgrades
• Heavy-duty diesel rebuilds
• Fleet engine shops
• Sealing integrity maintenance

Why Professional Shops Trust ATC-8240

CAT rebuilders rely on the ATC-8240 for its PT-8240 equivalence, precision dimensions, and ability to avoid $9,500–$19,500 in damages per failure. It offers stable seating, cost-effective repairs, and bulk pricing for shops.

From deck pitting to crack fixes, this insert keeps CAT engines reliable.

---