Counterbore Pilot-Volvo D13/Mack MP8

This counterbore pilot is designed to accurately locate and guide the injector seat counterbore cutter in Volvo D13 and Mack MP8 cylinder heads. Used as part of the Irontite Volvo D13 / Mack MP8 Injector Sleeve Professional Kit (PN 451‑6681‑00), it fits into the injector bore and centers the End Facing Counter Bore Cutter (PN 445‑6683‑30) so only the minimum amount of metal is removed from the injector sleeve seat before installing a new stainless steel sleeve (PN 419‑6681‑05).

Counterbore Pilot – Volvo D13 / Mack MP8

This counterbore pilot is a precision guide component used to center and stabilize the injector seat counterbore cutter in Volvo D13 and Mack MP8 cylinder heads. It fits into the injector bore and serves as the alignment reference for the End Facing Counter Bore Cutter (PN 445‑6683‑30), ensuring the cutter tracks true to the original seat location.

Accurate guidance of the cutter is essential to restore a clean, flat sealing surface for the new injector sleeve without removing excessive material.

Application-Specific for Volvo D13 & Mack MP8

• Designed to fit the injector bore in Volvo D13 cylinder heads
• Designed to fit the same bore in Mack MP8 cylinder heads
• Interfaces directly with the matching end facing counterbore cutter and guide bushing

Because the bore dimensions and seat geometry are specific to these engines, an application-matched pilot provides better centering and stability than generic pilots or improvised methods.

Role in the Counterboring Process

In Irontite’s Injector Sleeve Removal & Installation Manual (Doc PN 451‑3540‑13), this pilot is used when cleaning out the injector seat in the casting:

1. Assemble the cutter and pilot

   • Insert the pilot into the End Facing Counter Bore Cutter (PN 445‑6683‑30) and tighten the set screw.
   • The pilot can remain installed in the cutter unless it needs to be replaced.

2. Add the guide bushing

   • Slide the Guide Bushing (PN 416‑6158‑32) over the cutter on the end that goes into the injector bore.

3. Mount the assembly

   • Insert the cutter—with pilot and bushing installed—into the Driving Arbor (PN 414‑6114‑10).
   • Place the assembly into the injector bore in the cylinder head. The pilot locates in the bore and centers the cutter.

4. Apply cutting fluid

   • Use EA Lube (PN 468‑9910‑08) on the cutter and bore to keep the tool cool and cutting smoothly.

5. Cut only what’s needed

   • With the pilot guiding, remove just enough metal from the seat area to clean up pitting or corrosion, typically:
     • Minimum: 0.002”–0.003”
     • Maximum: 0.005”

The pilot maintains axial alignment as the cutter is fed down, helping produce a flat, concentric seat for the new stainless steel injector sleeve (PN 419‑6681‑05).

Why a Correct Pilot Matters

Using the proper counterbore pilot:

• Centers the cutter precisely in the original injector bore
• Prevents seat misalignment, which could compromise sealing or injector fit
• Improves surface quality, reducing chatter and uneven cutting
• Protects the head casting by reducing the risk of the cutter wandering or digging off-center
• Ensures repeatable results across multiple injector bores in the same head

Without a correctly sized pilot, even a quality cutter can produce a seat that is off-center, tapered, or uneven—leading to sealing issues with the new sleeve.

Part of the Volvo D13 / Mack MP8 Professional Kit

This counterbore pilot is supplied as part of the Irontite Volvo D13 / Mack MP8 Injector Sleeve Professional Kit (PN 451‑6681‑00), which includes:

• End Facing Counter Bore Cutter (PN 445‑6683‑30)
• Guide Bushing (PN 416‑6158‑32)
• Driving Arbor (PN 414‑6114‑10)
• Sleeve Removal Tool (PN 445‑6682‑10)
• Tip Expander and Tip Expander Driver (PNs 445‑6681‑21 and 445‑6681‑25)
• Combo Large Brush – Upper Bore/Face (PN 450‑6951‑07)
• Small Tip Bore Brush (PN 450‑6951‑08)
• EA Lube (PN 468‑9910‑08), Permatex 64000 Sleeve Retainer (PN 468‑9640‑00), Permatex Anti‑Seize (PN 468‑9771‑34), toolbox, and instructions

Shops can purchase this pilot individually as a replacement wear component or as part of building out a complete D13/MP8 injector seat tooling setup.

Ideal Users

• Diesel engine rebuilding shops
• Heavy‑duty truck and engine machine shops
• Fleet maintenance operations reconditioning Volvo D13 / Mack MP8 cylinder heads

Any shop performing injector sleeve seat cleanup or head rebuilding on these engines will benefit from having the correct pilot to guide the cutter.

Key Features

• Precision counterbore pilot for Volvo D13 / Mack MP8 injector bores
• Centers the End Facing Counter Bore Cutter (PN 445‑6683‑30) in the bore
• Works with the matching guide bushing (PN 416‑6158‑32) and driving arbor (PN 414‑6114‑10)
• Ensures accurate, concentric, and flat injector sleeve seats
• Helps minimize metal removal while restoring a clean sealing surface
• Included in Irontite’s Volvo D13 / Mack MP8 Injector Sleeve Professional Kit (PN 451‑6681‑00)