Sealed Power 7289MA .25MM Engine Crankshaft Main Bearing Set - MA Series Bi-Metal

The Sealed Power 7289MA .25MM Engine Crankshaft Main Bearing Set is a professional-grade MA Series bi-metal main bearing set engineered for reliable crankshaft support during engine rebuilds. Manufactured under ISO and QS certified processes, this set is designed to meet the demanding tolerances of modern engine rebuilding applications.

The MA Series bearing design features a unique bi-metal aluminum alloy (A-Series) construction. The bearing surface is composed of an aluminum-tin alloy with a small percentage of silicon, which provides excellent wear resistance and has the added benefit of gently polishing crankshaft journals that may not have been perfectly finished. This self-conditioning characteristic helps optimize oil film retention and reduce long-term wear.

Key Features:

• Bi-metal A-Series aluminum alloy bearing surface for superior wear resistance and corrosion protection
• Silicon-enhanced alloy gently polishes crankshaft journals for an optimized sealing surface
• High-strength 1010 steel backing for precise dimensional stability and wall variance control
• Improved seizure resistance for added protection under high-stress engine conditions
• Minimizes debris embedding to protect crankshaft journal surfaces from scoring
• 0.25MM undersize for use with reground or undersized crankshafts
• Half-groove design for proper oil distribution
• Manufactured to ISO and QS certified standards for consistent quality and fit

The Sealed Power 7289MA .25MM main bearing set is an ideal choice for engine rebuilders seeking a dependable, precision-fit solution for crankshaft main journal support. The .25MM undersize designation makes this set appropriate for engines with reground crankshafts machined to the corresponding undersize specification.