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Mercury 2.5L Standard Piston Ring Kit (3.500 Bore, Gold Pair, Top Pin) is designed for 2-Stroke Mercury Racing 2.5 Liter V6 engines; Mercury Racing 260 EFI, 280 ROS, 300 Drag, and S3000 Powerheads with Nikasil-plated sleeves. These specialized rings ensures proper compression, oil control, and heat transfer, contributing to engine longevity and performance.

 

Specifications:

  • Cross Reference Numbers: 817038, 817038A1, 817038A12, 8170381, 840663A12, 848201A12

  • Manufacturer Item: 39-840663A12

  • Manufacturer: Mercury Marine

  • Bore Size: 3.500 inches

  • Fitment: Standard size (STD) for Mercury 2.5L engines

  • Design: Gold pair with a top pin configuration

 

Function & Performance: This piston ring kit provides compression sealing for efficient combustion, controls oil film to minimize consumption and carbon buildup, and dissipates heat from the piston to the cylinder wall. The high-quality materials ensure wear resistance and durability in demanding conditions.

 

Compatibility & Applications: Designed for high-performance outboards and racing applications, this ring kit reduces blow-by and improves power output. It is engineered to fit Mercury Racing 260 EFI, 280 ROS, 300 Drag, and S3000 Powerheads with Nikasil-plated sleeves.

 

Installation & Maintenance: Proper cylinder wall preparation is essential before installation to optimize ring seating. Manufacturer torque specifications should be followed during piston assembly. Routine maintenance, including compression checks and wear inspections, helps maintain engine performance.

 

Incluce one (1) Gold Ring Set (two rings), 6 are required for a full rebuild. Contact Mike at 714-697-1716 or mike@buckshotracing77.com for technical support.

Gold Ring Set, Top-Pinned, Mercury Racing 848663-A12

SKU: 840663-77
$129.00Price
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