Approved by the National Marine Manufacturers Association NMMA FC-W for use in 4-Stroke Outboard Motors
AMSOIL Formula 4-Stroke Synthetic 10w30 and 10w40 Marine Engine Oils (Product Codes: WCT, WCF) are recommended for gasoline-fueled 4-stroke outboard, marine inboard and PWC (personal watercraft) motors. They are NMMA FC-W approved and “warranty certified.” The appropriate viscosity grade may be used in the following marine engines:
Excellent for use in 4-stroke outboard motors including: Bombardier/BRP, Honda, Johnson Evinrude (BRP), Mercury, Nissan, Suzuki, Tohatsu, Yamaha
Excellent for use in marine inboard engines including: Chevrolet, Chrysler Marine, Crusader, For, GM, Marine Power, MerCruiser (Mercury), OMC, Volvo Penta
Recommended for use with PWC (personal watercraft) including: Sea-Doo (BRP), Honda, Polaris, Yamaha
AMSOIL Formula 4-Stroke Full Synthetic 10w30 and 10w40 Marine Engine Oils are a premium quality synthetic oil formulations engineered for the harsh operating conditions of marine engine environments. They withstand the intense mechanical action of continuous, high-RPM operation to deliver superior viscosity protection. AMSOIL Formula 4-Stroke Marine Engine Oils are specially fortified with a heavy treatment of advanced additives that protects motors against rust, wear, and deposits. They excel in both high-horsepower applications and all-day trolling conditions.
- Formulated specifically for use in 4-stroke gasoline engines used in marine applications – outboard, inboard, inboard outboard (I/O) and PWC (personal watercraft).
- NMMA FC-W approved and “Warranty Certified”
- Excellent protection against engine rust
- Offers unsurpassed wear protection and viscosity stability
- API SL, FC-W
AMSOIL Formula 4-Stroke Full Synthetic 10w30 Marine Engine Oil Product Code Pkg/Size WCTQT-EA Quart Bottle WCTQT-CA Quart Bottles (case of 12) WCT30-EA 30-Gallon Drum WCT55-EA 55-Gallon Drum AMSOIL Formula 4-Stroke Full Synthetic 10w40 Marine Engine Oil Product Code Pkg/Size WCFQT-EA Quart Bottle WCFQT-CA Quart Bottles (case of 12) WCF30-EA 30-Gallon Drum WCF55-EA 55-Gallon Drum
NMMA Certified FC-W Oil
AMSOIL Formula 4-Stroke Full Synthetic Marine Engine Oils are certified by the National Marine Manufacturers Association (NMMA) for use in 4-stroke outboard motors. These high-quality oils demonstrate outstanding performance and meets the NMMA FC-W (Four Cycle-Water) Catalyst Compatible specification requirements. AMSOIL Formula 4-Stroke Marine Engine Oils fulfill the warranty requirements of 4-stroke outboard motor manufacturers.
Excellent Anti Rust Performance in Marine Engines
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. AMSOIL Formula 4-Stroke Marine Engine Oils are fortified with a special anti-rust agent, even more than required to pass stringent NMMA FC-W and FC-W Catalyst Compatible anti-rust test.
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. 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. To ensure good protection and long-term durability, the NMMA introduced the FC-W Catalyst Compatible standard, which is backward-compatible with the recognized requirements of the FC-W standard. AMSOIL Formula 4-Stroke Marine Synthetic Motor Oil meets the FC-W and FC-W Catalyst Compatible shear stability requirements, outperforming competitive oils to deliver a superior lubricating film.
Four-stroke outboards feature vertically mounted crankshafts, limiting oil retention at shutdown and increasing the likelihood of dry starts and accelerated wear. AMSOIL Formula 4-Stroke Marine Engine Oils contain a high concentration of premium-quality anti-wear additives that provide an extra level of wear control upon start-up (see Four Ball Wear Test graph below).
AMSOIL Formula 4-Stroke Synthetic Marine Oil Wear Comparison – 10w30 (left) and 10w40 (right)
Exceeds Both the API and NMMA FC-W Requirements for Shear Stability
In addition to be subjected to higher RPMs, 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 Synthetic Marine Engine Oils are shear stable and formulated with sophisticated oil additive chemistry, exceeding the HTHS requirements of both the API and NMMA FC-W (see High-Temp/High-Shear Test graph below).
AMSOIL Formula 4-Stroke Synthetic Marine Oil High-Temperature/High-Shear – 10w30 (left) and 10w40 (right)
AMSOIL Formula 4-Stroke Synthetic Marine Engine Oils (WCT, WCF) are recommended for gasoline fueled 4-stroke outboard, inboard, inboard/outboard (I/O) and PWC (personal watercraft) motors. Use the appropriate viscosity grade where specified in the following:
- Volvo Penta
Note: AMSOIL Formula 4-Stroke Marine Synthetic 10w30 is recommended for use in place of 5w30 as specified by Honda.
Note: AMSOIL Formula 4-Stroke Marine Synthetic 10w40 is recommended for use in place of 25w40 as specified by Mercury.Attention Power Sports Enthusiasts!
AMSOIL Online Application Guides contain lube and filter specifications for motorcycles, ATVs, UTVs, snowmobiles, PWC (personal watercraft) and marine outboards.
Four-stroke outboard motors and PWC (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 Synthetic Marine Engine Oils meet or exceed the following performance test requirements and may be used in motors requiring oils meeting these specifications:
- API SM
- NMMA FC-W Catalyst Compatible
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Please visit the AMSOIL, Inc. website: AMSOIL Shipping, Sales Tax and Product Return Guidelines