Mercury - Brg. Cup Spacer - 31-8M0048520. The Mercury - Brg. Cup Spacer - 31-8M0048520 is a genuine OEM component designed to maintain proper bearing alignment and spacing within your Mercury outboard assembly. Engineered to factory specs, this spacer ensures smooth, consistent operation of rotating components and protects against premature wear.. Key Features. OEM Quality Construction - Manufactured to Mercury's exacting standards for optimal durability and performance. Precision Fit - Ensures accurate bearing spacing to support smooth gear and shaft function. Corrosion-Resistant - Built with materials that withstand marine environments and reduce risk of degradation. Essential Load Distribution - Helps evenly distribute pressure across bearing assemblies for longer service life. Compatibility. The Mercury - Brg. Cup Spacer - 31-8M0048520 is compatible with select Mercury outboard motors. Always confirm part compatibility with your model and serial number, or contact PartsVu's team fo