Mercury 8M0229798 – Optimax DFI 2‑Stroke Synthetic Blend Engine Oil, 1 Gallon

Premium OEM oil for Mercury and OptiMax direct fuel-injected 2-stroke outboards – high-performance lubrication and carbon control.

Product Overview

Mercury 8M0229798 is a direct fuel injection (DFI) 2-stroke engine oil, specially engineered for use in Mercury, Mariner, and OptiMax DFI outboards. This premium formula provides maximum lubricity, carbon deposit control, and corrosion resistance—ensuring cleaner operation, reduced scuffing, and extended engine life.

Ideal for high-performance DFI systems, this oil meets or exceeds all major 2-stroke marine engine manufacturer recommendations for direct-injected engines. Comes in a 1-gallon (3.78L) bottle for easy refilling.

Key Features

• Designed for DFI 2-stroke outboards including Mercury, Mariner & OptiMax
• Increased lubricity & scuff protection for direct-injection systems
• Minimizes carbon buildup in combustion chamber and exhaust ports
• Outstanding corrosion & wear resistance for saltwater and freshwater use
• Meets or exceeds all OEM warranty requirements for DFI 2-stroke applications
• Supplied in a 1-gallon (3.78 L) container

Engine Compatibility

• Mercury DFI outboards
• Mariner DFI outboards
• Mercury OptiMax 2-stroke engines
• Other direct-injection 2-stroke marine engines requiring TC-W3 or DFI oil
• Supersession: 8M0229798, 858037K01, 877694K01 

Always refer to your owner’s manual for application-specific guidance.