Product Highlights
AMSOIL Synthetic Marine Engine Oil is a premium synthetic formulation designed to withstand the heat and stress of high-rpm operation and deliver excellent wear protection. It protects against rust and corrosion during periods of inactivity and long-term storage to keep your engine protected, even when it’s not running. Synthetic Marine Engine Oil is perfect for hardcore anglers and boating enthusiasts who demand the best protection for their marine engines.

10w40 Synthetic Marine Engine Oil

Protects Against Wear
Marine engines operate under high loads and rpm for extended periods. On average, a marine engine powering a boat 30 mph runs at about 5,000 rpm. In contrast, an automotive engine powering a car 60 mph runs at about 2,000 rpm. Higher stress causes traditional automotive oils to break down and lose viscosity. AMSOIL 25W-40 Synthetic Blend Marine Engine Oil is designed with excellent shear stability to deliver a consistent lubricating film. It helps guard engine components from wear for maximum life.NMMA

Excellent Anti-Rust Performance
Marine engines are prone to rust and corrosion due to constant exposure to humid, wet environments. Rust on engine parts acts like sandpaper, scouring bearings, the cylinder wall, piston rings and other components, while aluminum pistons and other parts can corrode. Rust and corrosion reduce engine power and eventually cause catastrophic failure.

Good rust protection is not natural to motor oil; it comes only by design. AMSOIL 25W-40 Synthetic Blend Marine Engine Oil is fortified with potent inhibitors that guard against damaging rust and corrosion.

  • Excellent high-stress, high-rpm endurance
  • Increased rust and corrosion protection

NMMA Certified
AMSOIL 25W-40 Synthetic Blend Marine Engine Oil is certified by the National Marine Manufacturers Association (NMMA) for use in four-stroke outboards, inboards, stern-drives (inboard/outboards) and PWC. This high-quality oil demonstrates outstanding performance and exceeds the NMMA “FC-W” (Four Cycle – Water) specification requirements.

  • FC-W (CAT)® Registration Number: FC-11825T

* All trademarked names and images are the property of their respective owners and may be registered marks in some countries. No affiliation or endorsement claim, express or implied, is made by their use. All products advertised here are AMSOIL-engineered for use in the applications shown.

APPLICATIONS
Use in gasoline-fueled four-stroke inboards, outboards, inboard/outboards and personal watercraft that require any of the specifications listed below, including those made by Mercury* and Mercruiser*.

  • API SM
  • NMMA FC-W Catalyst Compatible

SERVICE LIFE
Four-stroke outboard motors and personal watercraft: Due to potential fuel dilution or water contamination, change oil at the engine or watercraft manufacturer-recommended interval. Inboard and I/O applications: Change oil at two times the engine manufacturer-recommended interval, or once a year, whichever comes first.

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