Replacement Cylinder Sleeve 4.3750 Bore

The Replacement Cylinder Sleeve 4.3750 Bore by Melling is an essential component for engine builders and mechanics performing cylinder reconditioning work. This precision-engineered sleeve addresses worn, scored, or damaged cylinder walls that compromise compression, increase blow-by, and reduce engine efficiency. Whether you're rebuilding a classic engine, restoring marine power plants, or repairing industrial equipment, a quality cylinder sleeve restores cylinders to factory specifications without requiring complete engine block replacement—a cost-effective solution for serious enthusiasts and professional shops.

Melling's replacement cylinder sleeve features a 4.3750-inch bore diameter, designed to precise tolerances that ensure proper piston clearance and ring sealing. Cast from durable iron or steel material, the sleeve is honed to match OEM specifications, providing a fresh, corrosion-resistant surface for reliable ring seal and minimal oil consumption. The sleeve's 9.5-inch length accommodates standard block depths, while its compact 5.3 x 5.2-inch footprint maintains structural integrity during installation. Proper sizing prevents future wall degradation and maximizes ring life by eliminating the micro-gaps that develop in worn cylinders.

This sleeve suits any mechanic or engine builder tackling mid-range displacement engines requiring the 4.3750-inch bore specification. Installation demands precision honing equipment and careful press-fitting to ensure no gaps between sleeve and block; improper seating leads to coolant leakage and compression loss. Compatible with conventional wet-sleeve designs, the sleeve pairs seamlessly with modern piston and ring kits during full engine overhauls. For marine engines, performance rebuilds, or industrial power applications, Melling's proven durability and tight manufacturing tolerances make this a reliable choice for engines demanding years of dependable service.