SAE 10W-30 Formula 4-Stroke® Marine Synthetic Motor Oil (WCT)
 SAE 10W-30 Formula 4-Stroke® Marine Synthetic Motor Oil (WCT) 10W30

AMSOIL 10W-30 Formula 4-Stroke® Marine Synthetic Motor Oil (WCT) 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.

Package sizes include:

1-Quart Bottle
1-Quart Bottles (case of 12)
55-Gallon Drum

Product Code: WCT • Brand: AMSOIL




MSDS Data Sheet

Product Details Tech Data Reviews & Rating

Product Applications
AMSOIL Formula 4-Stroke® Marine Synthetic 10W-30 Motor Oil (WCT) is recommended for gasoline fueled four-stroke outboard, inboard, inboard/outboard (I/O) and personal watercraft motors. AMSOIL WCT motor oil is recommended for the following applications whenever an SAE 5W-30, 10W-30 or straight SAE 30 oil is called for:

Product Application Specs

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-30 is recommended for use in place of 5W-30 as specified by Honda®.

NMMA FC-W • API SL

Product Description
AMSOIL 10W-30 Formula 4-Stroke® Marine Synthetic Motor Oil (WCT) 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-30011B 10W-30

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).

Four Ball Wear test

HTHS 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. 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).

HTHS Viscosity

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).

Click here to view the MSDS Data Sheet for AMSOIL WCT.

Keep out of the reach of children. Don't pollute. Return used oil to collection centers.

TYPICAL TECHNICAL PROPERTIES
 AMSOIL FORMULA 4-STROKE® MARINE SYNTHETIC MOTOR OIL (WCT)
SAE 10W-30, API SL, NMMA FC-W
Kinematic Viscosity @ 100°C, cSt (ASTM D-445) 11.7
Kinematic Viscosity @ 40°C, cSt (ASTM D-445) 74.5
Viscosity Index (ASTM D-2270) 152
CCS Viscosity, cP @ (°C) (ASTM D-5293) 6032 (-25)
Flash Point °C (°F) (ASTM D 92) 236 (457)
Fire Point °C (°F) (ASTM D 92) 258 (496)
Pour Point °C (°F) (ASTM D 97) -48 (-54)
Noack Volatility, % weight loss (g/100g) (ASTM D-5800) 4.8%
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) 3.64
Humidity Cabinet Rust (ASTM D-1748) Pass

Did this product meet your expectations?

(click on a star to rate)
Product Name: SAE 10W-30 Formula 4-Stroke® Marine Synthetic Motor Oil (WCT)
Current Rating: 4.33 out of 5 stars
Total Votes: 6 vote(s)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by matt: space

best of the best!!

having a $15k investment and protecting it starts with Amsoil. I use it in everything I own an have had ZERO problems.

Item Reviewed: SAE 10W-30 Formula 4-Stroke® Marine Synthetic Motor Oil (WCT)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by tootall: space

Will buy this product again

Use in my 150HP and 9.9HP Suzuki Outboards

Item Reviewed: SAE 10W-30 Formula 4-Stroke® Marine Synthetic Motor Oil (WCT)

A Verified Buyer is an individual who has purchased the reviewed product and submitted their review through a specific process that tracks purchase history.Reviewed by Ronald: space

Best oil I've used in my four-strokes!!!!

I have been using this in my 4 strokes for 10 years- first in Honda 130's and now in Yamaha f250's. I have used Mobil 1, Honda and Yamaha oils and the amsoil is always cleaner at the end of the season and still has a goldish brown color.

Item Reviewed: SAE 10W-30 Formula 4-Stroke® Marine Synthetic Motor Oil (WCT)

Reviewed by James B: space

Honda BF115

Switched to 10W-30 Formula 4-Stroke marine oil in a Honda BF115 2.3L outboard motor and immediately noticed reduction in engine noise. It hums along much more quieter in all rev ranges, its just that much more smoother to operate this motor. The fuel economy is also better, able to go further with the same amount of fuel. All of it indicating one thing... reduction is internal friction! Will continue to use this product.

Item Reviewed: SAE 10W-30 Formula 4-Stroke® Marine Synthetic Motor Oil (WCT)
Discussion Url
Share your AMSOIL Experience
by writing a review
smaller | bigger





Click Here to Report Problems Or Comments
3 Easy ways to place your order now!



Receive AMSOIL's Confidential Factory Direct Wholesale Price List in your email.
Enter your first name & email address and click on "eMail Price List" button!
AMSOIL Online Store
AMSOIL Preferred Customer Program. Save upto 25%!
Wholesale Business Accounts
Become an AMSOIL Dealer!
Request FREE AMSOIL Catalog
Questions? Please Contact us
Order AMSOIL By Phone
AMSOIL Online Store
Order AMSOIL By Fax
VISA and MASTERCARD is accepted for US and Canada.
Discover and American Express is accepted for US customers only
Go to Top