Sierra 18-36850 Needle & Seat Assembly for MerCruiser 2.5L and 3.0L Carburetors

The Sierra 18-36850 Needle & Seat Assembly is a high-quality carburetor replacement component designed for MerCruiser 2.5L and 3.0L marine engines. The needle and seat work together as the primary fuel metering components inside the carburetor, controlling fuel flow into the float bowl to ensure proper air-fuel mixture and reliable engine performance.

Sierra engineers this assembly to meet or exceed OEM specifications, delivering a direct-fit replacement that restores proper carburetor function. A worn or leaking needle and seat can cause flooding, rough idling, poor fuel economy, or hard starting — making this a critical service part during any carburetor rebuild or overhaul.

Key Features:

• Direct replacement needle and seat assembly for MerCruiser 2.5L and 3.0L carburetors
• Manufactured to meet or exceed original equipment specifications
• Controls fuel flow into the carburetor float bowl for proper fuel metering
• Restores correct float level and prevents carburetor flooding
• Interchangeable with Mallory 9-37311 and Mercury Marine 1395-8116913
• Sold as a complete needle and seat assembly

Sierra is a trusted name in marine replacement parts, offering broad coverage across major engine brands including Mercury/MerCruiser, Yamaha, Johnson/Evinrude, and Volvo Penta. The Sierra 18-36850 is an ideal solution for technicians and do-it-yourself boaters performing carburetor service or rebuild work.