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Random Quote: Nobody likes a Redneck, until their car breaks down -- BUGBUSTER
I started running Castrol Syntec 10-40 in my Yamahas after I bought them with 340 hrs. I immediately gained 200 rpm's on top end. I did one oil change after 50 hrs and will do the next after 100 hrs....
1-Quart Bottle 1-Quart Bottles (case of 12) 55-Gallon Drum
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. 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-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: 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
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.
I plan on using synthetic the next time I change my oil in my f115.
Get a couple of Yamaha filters and some new drain plugs from Andy at SIM ( forum vendor)
Keep those drain plugs torqued properly and they will last a good while. If overtorqued they could develop a leak....
Get a couple of Yamaha filters and some new drain plugs from Andy at SIM ( forum vendor)
Keep those drain plugs torqued properly and they will last a good while. If overtorqued they could develop a leak....
Dont really know if this means anything, but when I had my boat in for some warranty work I was talking with the shop forman and asked him what was his thought on Amsoil syn. and he said he uses it in his personal Yami, but he has to use the Yamalube when servicing there at the shop. That being said I have 10w30 marine synthetic in the garage waiting for my first oil change.
I have been using amsoil marine 10w-40 for 300 hours havent had a problem but the mech at yamaha said if water get in oil that syn oils dont mix as good with water like reg oil. I havent had any water in my oil that i could see. I change my oil about every 150 hours. I hope amsoil is good stuff because my motor cost 17000 grand.
I havent had any water in my oil that i could see. I change my oil about every 150 hours. I hope amsoil is good stuff because my motor cost 17000 grand.
With a 17K investment why are you not changing the oil every 100 hours like the manual says???
__________________ "I'm suing the THT and the guy that made it."
I was sponsored by AMSOIL for 3 years while I was racing Motocross. I used their products in my Bike's & Truck. I didnt notice a difference in my truck but it sure did make a huge difference in my bike's. They ran nice & smooth, clutch worked alot smoother also.
Try it out and get back with us. I am sure you will notice it idling & cruising alittle smoother. Give it a try...you only live once
I have been using amsoil marine 10w-40 for 300 hours havent had a problem but the mech at yamaha said if water get in oil that syn oils dont mix as good with water like reg oil. I havent had any water in my oil that i could see. I change my oil about every 150 hours. I hope amsoil is good stuff because my motor cost 17000 grand.
Your mech is a joke. Dino oil will hold up better than sync oil if water intrusion is involved. Either way its BAD!
Go to Blackstone-Labs.com and do a Oil Analysis. It will show how your engine is internally. Showing all the metals, liquids that are in your oil.
AMSOIL Instead of Yamalube in F250 Outboard?? 
4-Stroke Outboard Motor Warranty Certified
I need a couple filters and may as well get a couple plugs. 
. Dino oil will hold up better than sync oil if water intrusion is involved. Either way its BAD!
