I am new to the Yamaha jet boats. I agree that law prohibits a dealer from forcing you to buy his product. I was also told by the dealer that you must use Yamalube for your warranty.
I did some research and found out why I believe Yamaha is so strict about their oil.Yamaha oil is mineral based oil (4W 10W40) which is what I need in my 242 Limited SE. According to Yamaha, "Yamalube is the only oil “built around” the unique demands, operating characteristics and applications of Yamaha engines. Collaborating with Yamaha engine designers, our global oil engineers formulate each Yamalube oil from scratch, to be engine- and application-specific. In other words, nothing enhances the performance or protects the advanced design of a Yamaha quite like Yamalube.
"Yamalube is supposedly specifically designed for high output, high RPM engines and provides for 4 things:High “Shear Stability”High “Oil Film Retention”Motorsports engines run at high rpm and high-load conditions—much higher than cars. As such, they require oils that can withstand these demands, maintain their viscosity and feature advanced additives for oil film retention. Under these punishing conditions, a lesser oil’s molecules will break down or “shrink,” causing unnecessary wear and tear on your engine.
High “Oxidation & Thermal Stability”Motorsports oil must be able to withstand harsh thermal conditions in order to properly and effectively lubricate the engine and transmission. This requires highly refined base oil with additives to prevent oxidation. Otherwise, the oil will break down, compromising lubrication, and will create acidic compounds that lead to corrosion, sludge, varnish and possible piston seizure.
Friction ModifiersMotorsports engines must not use oils featuring high levels of friction modifiers. Friction modifiers can compromise wet clutch operation, cause slippage, decrease fuel economy and cause a rough run.
Many car oils feature high levels of friction modifiers in order to achieve the government mandated fuel mileage.All Yamalube four stroke marine oils are NMMA® FC-W® certified. What does this mean?Well, the National Marine Manufacturers Association (NMMA®) has worked with industry leaders to establish testing criteria and performance standards for four stroke marine oil.Before an oil can achieve NMMA® FC-W® certification, it must pass a 100-hour general performance engine test, as well as bench tests for viscosity, filter plugging, foaming and aeration.
To gauge rust and corrosion resistance, the NMMA® FC-W® oil committee has developed the industry’s most punishing test. This proprietary test simulates a brutal marine environment, subjecting actual steel cylinder sleeves to extreme moisture and salt. Automotive oils simply aren’t formulated to withstand these harsh conditions, so they won’t come close to meeting the demanding NMMA® FC-W® standards.Oils that earn FC-W® certification have been proven to provide the performance and quality demanded by today’s advanced four stroke outboard technology.
These oils stand up to extended full-throttle operation, high loads and the salt and moisture-rich air found in a harsh marine environment.If you look on NMMA's website they list those oils that are NMMA FC-W certified. None of the top name automotive oils (Mobil 1, Castrol, etc.) are listed.
Bottom line that I take from all of this is as long as the oil you use meets Yamaha OEM standards, and is NMMA FC-W certified you have nothing to worry about. So, I will stick with the Yamalube....Mobil One runs about $8 a quart, and I can get the Yamalube at my dealer for $35 for a gallon jug. I have no horse in this race, except my 2 engines that are warranteed for 4 years....so that is my incentive to stick with Yamalube!
