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AMSOIL - "Our Company makes the Best Lubricants in the world, period, and challenges anyone or any company to prove us wrong! That won't happen because our competitors know it's true."....... A. J. Amatuzio, President and CEO.


"The First in Synthetics" ®
Outstanding performance



SYNTHETIC

10W-40
Marine Motor Oil


SAE 10W-40 Formula 4-Stroke® Marine Synthetic Motor Oil (WCF)

AMSOIL 10W-40 Formula 4-Stroke® Marine Synthetic Motor Oil (WCF) 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.

Product Code: WCF


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, exceeding 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-30010B 10W-40

PRODUCT DESCRIPTION

AMSOIL 10W-40 Formula 4-Stroke® Marine Synthetic Motor Oil (WCF) 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 protects motors against wear, rust and deposits. It excels in both high horsepower applications and all-day trolling conditions.

Superior Protection Against Engine Wear

Marine engines operate under high loads and RPMs 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 also contains robust anti-wear additives that further reduce wear in metal-to-metal contact regions (see Four-Ball Wear Test graph).

While automobile engines normally operate at around 2,500 rpm, outboard motors can run twice as fast, requiring greater levels of wear protection and better bearing durability than automobiles. In addition, prolonged idling and low operating temperatures contribute to fuel dilution, further thinning the oil. To ensure adequate protection for their engines, marine engine manufacturers set minimum high temperature/high shear (HTHS) viscosity limits.

AMSOIL Formula 4-Stroke® Marine Synthetic Motor Oils are shear stable and formulated with sophisticated oil additive chemistry, exceeding the HTHS requirements of both the API and
NMMA FC-W (see graph).

Excellent Anti-Rust Performance

Marine engines are prone to rust, leading to uncontrolled wear and premature engine failure. However, 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 10W-40 Motor Oil (WCF) is recommended for gasoline fueled four-stroke outboard, inboard, inboard/outboard (I/O) and personal watercraft motors. AMSOIL WCF motor oil is recommended for the following applications whenever an SAE 10W-40, 15W-40, 25W-40 or straight SAE 40 oil is called for:

  • 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®
  • NMMA FC-W • API SL
    Note: AMSOIL Formula 4-Stroke® Marine Synthetic 10W-40 is recommended for use in place of 25W-40 as specified by Mercury®
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.

Mixing AMSOIL

AMSOIL Formula 4-Stroke® Marine Synthetic Motor Oil is compatible with conventional and synthetic motor oils. Mixing AMSOIL motor oils with other oils will, however, shorten the oil 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). MSDS’s are available upon request at 715-392-7101 or on our website. Keep Out of Reach of Children. Don’t pollute. Return used oil to collection centers.


TYPICAL TECHNICAL PROPERTIES

 AMSOIL FORMULA 4-STROKE® MARINE SYNTHETIC MOTOR OIL (WCF)
SAE 10W-40, API SL, NMMA FC-W

Kinematic Viscosity @ 100°C, cSt (ASTM D-445)

14.1

Kinematic Viscosity @ 40°C, cSt (ASTM D-445)

93.8

Viscosity Index (ASTM D-2270)

154

CCS Viscosity, cP @ (°C) (ASTM D2602)

6871 (-25)

Flash Point °C (°F) (ASTM D 92)

234 (453)
Fire Point °C (°F) (ASTM D 92) 254 (489)
Pour Point °C (°F) (ASTM D 97) -46 (-51)

Noack Volatility, % weight loss (g/100g) (ASTM D-5800)

6.40%

Four Ball Wear Test (ASTM D 4172 @ 40 kgf, 150°C, 1800 rpm, 1 hour, Scar in mm)

0.40
Total Base Number (ASTM D-2896) 10.5
HTHS (cP) 4.6
Humidity Cabinet Rust (ASTM D-1748) Pass

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