Don't let liner drop compromise your rebuild. The ATC30144 Counterbore Shim Cutter Plate is the precision machining upgrade required to re-face worn blocks in-frame.

The Crucial Physics of Counterbore Seating

On a high-mileage Detroit Diesel Series 60 engine, the block counterbore ledge bears intense combustion loads. Over time, micro-fretting and physical erosion cause this ledge to settle, allowing the cylinder liner to sink below the deck surface. When liner protrusion drops, uniform cylinder head gasket crush becomes impossible, resulting in repeating head gasket blowouts, internal coolant leaks, or fractured liner flanges. The ATC30144 adapter plate provides the exact machining geometry to clean up these damaged ledges in-frame. Functioning as a direct replacement for the **J-41065 Conversion Kit**, it updates your existing tool chassis to cut a perfectly flat, uniform counterbore radius that welcomes repair shims with zero edge deflection.

• Direct OEM Blueprint Match – Form-fit functional direct replacement for the factory Kent-Moore part number **J-41065 conversion kit**.
• Chassis Tool Compatibility – Designed exclusively to integrate seamlessly with the **PT-2250** or **M50133** tool setups (Note: will not work on PT-2050D frames).
• In-Frame Repair Capability – Saves thousands in labor by allowing technicians to cut and machine counterbores directly inside the truck frame without removing the block.
• Eliminate Liner Stress – Establishes a mirror-flat cut that distributes clamping forces evenly, minimizing the risk of flange stress fractures.
• Shop-Grade Weight Profile – A solid, 8.00 lbs precision-ground steel casting engineered to eliminate cutting chatter and ensure a flat surface profile.

Stop Swapping Gaskets. Machining Saves Blocks.

The ATC30144 Counterbore Cutter Plate is an indispensable asset for commercial heavy-duty truck stations, fleet operations centers, and independent diesel machine builders. Bring factory tolerance control back to your engine rebuild bay.

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