AMSOIL SAE 10W-40 Formula 4 Stroke®
Marine Synthetic Motor Oil (WCF)
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Package sizes include:
1-Quart Bottles (case of 12)
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.
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
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.
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®,
Inboard and I/O: Mercruiser®, Volvo Penta®, OMC®, Chrysler® Marine, Crusader®, Marine Power®, Chevrolet®,
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
NMMA FC-W • API SL
- 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.
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.
TYPICAL TECHNICAL PROPERTIES
AMSOIL FORMULA 4-STROKE® MARINE SYNTHETIC MOTOR OIL
SAE 10W-40, API SL, NMMA FC-W
Kinematic Viscosity @ 100°C, cSt (ASTM D-445)
Kinematic Viscosity @ 40°C, cSt (ASTM D-445)
Viscosity Index (ASTM D-2270)
CCS Viscosity, cP @ (°C) (ASTM
Flash Point °C (°F) (ASTM D 92)
|Fire Point °C (°F) (ASTM D 92)
|Pour Point °C (°F) (ASTM D 97)
Noack Volatility, % weight loss (g/100g) (ASTM D-5800)
Four Ball Wear Test (ASTM D 4172 @ 40 kgf, 150°C, 1800 rpm, 1 hour,
Scar in mm)
|Total Base Number (ASTM D-2896)
|Humidity Cabinet Rust (ASTM D-1748)