AMSOIL 10W-40 100% Synthetic Marine Engine Oil

AMSOIL 10W-40 Synthetic Marine Engine Oil is a premium formulation specifically engineered for the harsh operating conditions of marine environments. It is designed to withstand the intense mechanical activity of continuous, high RPM operation, delivering superior viscosity protection and preventing engine wear. The oil's durable formulation ensures reliable performance in severe conditions, ranging from all-day trolling to high-speed operation. It is heavily fortified with advanced additives, which are essential for preventing deposits, rust, and corrosion in marine engines. AMSOIL's 10W-40 Marine Engine Oil's naturally strong base oils resist viscosity loss due to mechanical shear, developing a tough lubricating film that protects engine parts even in high-heat, high-rpm conditions that can break down other oils​​​​​.

4.9
star rating from
110
total reviews

This AMSOIL product is available in:

Individual Quart Bottles
Cases of 12 Quart Bottles
Individual 55 Gallon Drums
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Product Code:

WCFQT-EA

AMSOIL AMSOIL 10W-40 100% Synthetic Marine Engine Oil Description

AMSOIL 10W-40 Synthetic Marine Engine Oil is a premium formulation specifically engineered for the harsh operating conditions of marine environments. It is designed to withstand the intense mechanical activity of continuous, high RPM operation, delivering superior viscosity protection and preventing engine wear. The oil's durable formulation ensures reliable performance in severe conditions, ranging from all-day trolling to high-speed operation. It is heavily fortified with advanced additives, which are essential for preventing deposits, rust, and corrosion in marine engines. AMSOIL's 10W-40 Marine Engine Oil's naturally strong base oils resist viscosity loss due to mechanical shear, developing a tough lubricating film that protects engine parts even in high-heat, high-rpm conditions that can break down other oils​​​​​.

AMSOIL Synthetic Marine Engine Oil

10W-30 & 10W-40

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. AMSOIL Synthetic Marine Engine Oil is perfect for hardcore anglers and boating enthusiasts who demand the best protection for their marine engines.

AMSOIL 10W-40 100% Synthetic Marine Engine Oil
  • Excellent high-stress, high-rpm endurance
  • Increased rust and corrosion protection
  • NMMA FC-W Catalyst Compatible

Fights Engine Wear

AMSOIL Synthetic Marine Engine Oil’s naturally strong base oils resist viscosity loss due to mechanical shear. It develops a tough lubricating film that protects engine parts, even in high-heat, high-rpm conditions that break down other oils. AMSOIL Marine Engine Oil contains robust anti-wear additives that further reduce wear in metal-to-metal contact regions, guarding against compression loss for maximum power and engine life.

Excellent Anti-Rust Performance

Good rust protection is not natural to motor oil; it comes only by design. AMSOIL Synthetic Marine Engine Oil is fortified with potent inhibitors that guard against damaging rust and corrosion. It protects engines during use and during inactivity or long-term storage.

NMMA Certified

AMSOIL Synthetic Marine Engine 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 meets the requirements of the NMMA FC-W Catalyst Compatible specification, which is backward-compatible with the FC-W specification.

  • 10W-40 – FC-W (CAT)® Registration Number: FC-00850T
  • 10W-30 – FC-W (CAT)® Registration Number: FC-00833T

TYPICAL TECHNICAL PROPERTIES

AMSOIL 10W-40 Synthetic Marine Engine Oil (WCF)

Kinematic Viscosity @ 100°C, cSt (ASTM D445) 14.1
Kinematic Viscosity @ 40°C, cSt (ASTM D445) 93.3
Viscosity Index (ASTM D2270) 155
Pour Point, °C(°f) (ASTM D97) -38(-36)
Flash Point, °C(°f) (ASTM D92) 240(464)
High-Temperature/High-Shear Viscosity (ASTM D5481), cP 4.2
Four-Ball Wear Test (ASTM D4172), Scar, mm 0.40
NOACK Volatility, % weight loss (g/100g) (ASTM D5800) 7.5
Total Base Number (TBN) (ASTM D2896) 7.9

APPLICATIONS

Use in gasoline-fueled four-stroke inboards, outboards, inboard/outboards, supercharged watercraft engines and personal watercraft, including those made by Honda, Mercury, Yamaha, Johnson/Evinrude, Bombardier/BRP, Suzuki, Nissan, Tohatsu, OMC, Volvo-Penta, Mercruiser, Chevrolet and Ford.

NMMA FC-W Catalyst Compatible • API SM • JASO MA

SERVICE LIFE

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

COMPATIBILITY

AMSOIL Synthetic Marine Engine Oil is compatible with other synthetic and conventional motor oils. Adding other oils, however, will shorten the life expectancy of AMSOIL motor oil and reduce its performance benefits. AMSOIL does not support extended drain intervals where oils have been mixed.

Aftermarket oil additives are not recommended for use with AMSOIL Synthetic Marine Engine Oil.

TECHNICAL SERVICES

For immediate answers to your technical questions call (715) 399-TECH (8324) between 8 a.m. and 5 p.m. Central time or email tech@amsoil.com.

AMSOIL PRODUCT WARRANTY

AMSOIL Synthetic Marine Engine Oil is Warranty Secure, keeping your factory warranty intact. AMSOIL Synthetic Marine Engine Oil is a high-performance replacement for vehicle manufacturer-branded products and is also backed by the AMSOIL Limited Warranty. For complete information visit AMSOIL.com/warranty.aspx.

HEALTH & SAFETY

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

AMSOIL 10W-40 100% Synthetic Marine Engine Oil Reviews

5

star rating

MARINE ENGINE OIL

We have been using this oil in our 1991 4.3L engine for over a decade. The engine now has a few thousand hours on it. We use nothing but Amsoil in all our rigs (trucks, sleds, boat motors)

5

star rating

Only run the best

Have been using Amzoil for 17 year's have never had an oil related problem. Put marine oil in 300 hp mercury and 15 hp kicker the kicker was noticeable smoother running.

5

star rating

Marine oil

Great product. Used in a 2004 Seaswirl. No problems.

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