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Removing snapped or heat-seized exhaust manifold studs on a Caterpillar 3406 or 3408 diesel engine during an exhaust gasket replacement or top-end overhaul? Follow this step-by-step professional workshop procedure to mount the M10130 alignment plate, seat hardened drill bushings, drill centered pilot holes, collapse thread shanks, and clean internal cylinder head threads safely in-frame.

Why Freehand Drilling & Torches Ruin CAT Cylinder Heads

On Caterpillar 3406 and 3408 commercial diesel engines, exhaust manifold studs sit directly adjacent to internal cylinder head coolant jackets. When a stud snaps due to thermal fatigue, technicians who attempt freehand drilling run into immediate trouble. Handheld power drills wobble easily; because the broken steel stud is harder than the surrounding cast-iron cylinder head, the drill bit slips off the stud and bores directly into the cast iron. This wallows out the hole, ruins the threads, or breaches internal water jackets, causing coolant to flood the exhaust port. Heating the stud with an oxy-acetylene torch weakens surrounding head metallurgy, causing localized cracking along the manifold deck face. Utilizing the 10-pound M10130 Broken Exhaust Stud Removal Kit completely eliminates drilling errors. Its rigid baseplate anchors to existing head holes, centering hardened drill bushings squarely over the broken stud so technicians can drill straight through the center and peel old threads out cleanly.

The 5-Step CAT 3406/3408 Exhaust Stud Extraction Protocol

1. Remove Exhaust Manifold & Prep Broken Stud Port: Unbolt the exhaust manifold section to expose the broken stud shank. Clean dirt, carbon, and rust scale off the cylinder head deck face around the damaged port using shop solvent and wire brushes.
2. Mount M10130 Alignment Plate to Head Deck: Secure the M10130 baseplate to adjacent undamaged exhaust stud holes using the kit's mounting bolts. Hand-tighten bolts to lock the alignment plate dead-flat against the head face.
3. Insert Hardened Drill Bushing Over Broken Stud: Insert the initial small-diameter drill guide bushing into the M10130 alignment plate, positioning it squarely over the broken stud center.
4. Drill Concentric Pilot Hole Through Broken Stud: Coat drill bits with cutting fluid. Run drill bit at low RPM through the guide bushing, boring straight down through the centerline of the broken stud. Step up to the secondary drill bit size as directed in tooling instructions.
5. Collapse Remaining Thread Shell & Chase Head Threads: Remove the drill plate. Use the specialty extraction pin to collapse the thin remaining steel thread shell inward. Run a standard thread chase tap by hand to clean factory cylinder head threads before installing new OEM CAT studs.

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