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10W-40 Synthetic Formula 4-Stroke Marine Oil

10W-40 Synthetic Formula 4-Stroke Marine Oil Product Image

10W-40 Synthetic Formula 4-Stroke Marine Oil

For use in 4-stroke gasoline fueled engines in marine applications. Offers unsurpassed wear protection, viscosity stability, low volatility and excellent rust protection. NMMA FC-W approved and "warranty certified". For use in 4-stroke outboard and marine inboard engines. Also excellent for personal watercraft.

Product Code: WCFQT-EA Ordering Instructions
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Package sizes include:

  • Quart Bottles
  • 55-Gallon Drum



AMSOIL Formula 4-Stroke® Marine Synthetic Motor Oil is a premium-quality synthetic formulation engineered for the harsh operating conditions of marine environments. It withstands the intense mechanical action of continuous, high-rpm operation to deliver superior viscosity protection. Formula 4-Stroke Marine Synthetic Motor Oil is specially fortified with a heavy treatment of advanced additives that protect motors against wear, rust and deposits. It excels in high-horsepower applications and all-day trolling conditions.

4-Stroke Outboard Motor Warranty Certified
Formula 4-Stroke Marine Synthetic Motor Oil is certified by the National Marine Manufacturers Association (NMMA) for use in four-stroke outboard motors. This high-quality oil demonstrates outstanding performance and exceeds the NMMA “FC-W” (Four Cycle - Water) specification requirements. Formula 4-Stroke Marine Synthetic Motor Oil fulfills the warranty requirements of four-stroke outboard motor manufacturers.

NMMA Registration #FB-30012K 10W-40

Superior Protection Against Engine Wear
Marine engines operate under high loads and rpm for extended periods of time, causing traditional automotive oils to break down and lose viscosity. To ensure good protection, the NMMA set minimum shear stability requirements for FC-W. AMSOIL Formula 4-Stroke Marine Synthetic Motor Oil greatly exceeds the FC-W shear stability requirements, outperforming competitive oils to deliver a superior lubricating film. Formula 4-Stroke Synthetic Oil contains robust anti-wear additives that further reduce wear in metal-to-metal contact regions, while high zinc and phosphorus levels protect flat-tappet camshaft marine engines against wear.

Excellent Anti-Rust Performance
Marine engines are prone to rust, leading to uncontrolled wear and premature engine failure. Good rust protection is not natural to engine oil; it comes only by design. Formula 4-Stroke Marine Synthetic Motor Oil is fortified with a special anti-rust agent, even more than required to pass stringent NMMA FC-W anti-rust testing.

Applications
AMSOIL Formula 4-Stroke Marine Synthetic Motor Oil is recommended for gasoline-fueled four-stroke outboard, inboard, inboard/outboard (I/O) and personal watercraft motors. Use the appropriate viscosity grade where specified in the following:

  • Four-stroke outboard motors: Honda®, Mercury®, Yamaha®, Johnson®/Evinrude®, Bombardier/BRP®, Suzuki®, Nissan®, Tohatsu®
  • Inboard and I/O: Mercruiser®, Volvo Penta®, OMC®, Chrysler® Marine, Crusader®, Marine Power®, Chevrolet®, Ford®
  • Personal Watercraft: Honda®, Yamaha®, Bombardier/BRP® (Sea-Doo®), Polaris®
  • Note: AMSOIL Formula 4-Stroke® Marine Synthetic 10W-40 is recommended for use in place of 25W-40 as specified by Mercury®.
  • NMMA FC-W • API SL

Service Life

  • Four-stroke outboard motors and personal watercraft applications: 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 one year, whichever comes first.

Compatibility
AMSOIL Formula 4-Stroke Marine Synthetic Motor Oil is compatible with conventional and synthetic motor oils. Mixing AMSOIL motor oils with other oils, however, will shorten the oil's life expectancy and reduce the performance benefits. AMSOIL does not support extended drain intervals where oils have been mixed.

Aftermarket oil additives are not recommended for use with AMSOIL motor oils.

HEALTH & SAFETY
This product is not expected to cause health concerns when used for the intended application and according to the recommendations in the Material Safety Data Sheet (MSDS). An MSDS is available via the Internet at www.amsoil.com or upon request at (715) 392-7101. Keep Out of Reach of Children. Don’t pollute. Return used oil to collection centers.

For warranty information, visit www.amsoil.com/warranty.aspx.

TYPICAL TECHNICAL PROPERTIES

AMSOIL FORMULA 4-STROKE® MARINE SYNTHETIC MOTOR OIL (WCF)
SAE 10W-40

Kinematic Viscosity @ 100°C, cSt (ASTM D445) 14.0
Kinematic Viscosity @ 40°C, cSt (ASTM D445) 91.7
Viscosity Index (ASTM D2270) 157
Pour Point °C (°F) (ASTM D97) -46 (-51)
Flash Point °C (°F) (ASTM D92) 234 (453)
High-Temperature/High-Shear Viscosity (ASTM D5481)4.6
Four Ball Wear Test (ASTM D4172 @ 40 kgf, 150°C, 1800 rpm, 1 hour, Scar in mm) 0.40
Noack Volatility, % weight loss (g/100g) (ASTM D5800) 6.4
Total Base Number (ASTM D2896) 10.5