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Extracting wet cylinder liners during a heavy-duty engine overhaul? Follow this step-by-step professional workshop procedure to inspect universal liner puller assemblies, replace worn puller fingers with the M50010-20 thick feet set, position the puller crossbar squarely, engage the liner bottom lip, and pull liners smoothly without damaging engine block decks.

Why Inspecting and Replacing Worn Puller Feet Prevents Catastrophic Block Damage

Universal cylinder liner pullers rely on pivoting feet (fingers) that expand beneath the bottom edge of a wet liner sleeve. Because pulling force frequently exceeds several tons when breaking loose carbon-sealed liners, the tiny shoulders of these feet sustain incredible stress. Over multiple engine rebuilds, the contact lips of standard feet become rounded, chipped, or bent. Attempting to extract a stuck liner using damaged feet creates a severe safety hazard and risks costly engine block damage. A rounded foot slips under tension, causing the puller tool to jump upward instantly. This sudden release cocks the puller assembly sideways, slamming the heavy steel legs into the precision cylinder block deck or scratching the lower O-ring sealing lands inside the block. Scratched lower sealing lands allow engine coolant to leak into the oil crankcase after reassembly. Replacing worn fingers with the M50010-20 Thick Feet Set eliminates these extraction risks completely. The thicker profile provides a wider, flatter engagement surface that firmly hooks the liner bottom, keeping the tool centered and transferring 100% of rotational forcing screw torque into straight, upward extraction.

The 5-Step Puller Maintenance & Liner Extraction Protocol

1. Inspect Universal Liner Puller & Remove Worn Feet: Clean the liner puller assembly. Unthread the mounting screws holding the old gripping fingers to the spring-loaded lower block and remove worn feet.
2. Install M50010-20 Thick Feet & Secure Screws: Align the new M50010-20 thick feet onto the puller block pivot points. Insert the included new mounting screws and torque securely, verifying that the feet pivot freely without binding.
3. Position Puller Assembly Over Target Cylinder: Lower the puller legs onto the engine block deck surface. Ensure the support legs rest squarely on solid deck metal away from delicate counterbore edges.
4. Lower Puller Shaft & Engage Liner Bottom Lip: Push the puller shaft down through the cylinder liner until the spring-loaded M50010-20 feet pass below the bottom edge of the liner sleeve. Pull up slightly to feel the thick feet expand outward and lock firmly against the bottom liner rim.
5. Advance Forcing Screw to Extract Liner Cleanly: Turn the main forcing screw clockwise using a heavy wrench or breaker bar. Apply steady pressure as the forcing screw draws the shaft upward, popping the liner free from its carbon seat and lower O-ring grooves. Lift the pulled liner out of the block.

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