Yamaha V-MAX SHO VF250 Maintenance Manual page 22

What oil should I use?
Your Yamaha outboard is vastly different
from your automotive engine; so avoid regular
automotive engine oils. Use a motor oil
specifically formulated for the rigors of the
marine environment, like Yamalube
four-stroke outboards, and Yamalube
for two-stroke outboards.
Let's look at a few reasons why:
1
• Engine load.
automobile, having to overcome a much greater amount of drag to create performance. This
means your outboard is working much harder than your automobile's engine. Yamalube 4M
and 2M marine engine oils contain specific anti-wear additives to account for this.
2
Engine speed.
•
It must rev higher to create higher speeds, rather than just changing gears like your car.
That means your outboard may run all day long at 4500-6000 RPM, rather than the 2500 RPM
your car reaches at highway speeds. That's tough on your oil, and can literally shear (or
split) the molecules in ordinary automotive oil, reducing lubricity. Yamalube 4M and 2M have
special shear-stable polymers to combat this and provide superior lubrication at all times.
3
• Operating temperature.
cold. On the other hand, saltwater will begin to crystallize if its temperature is raised above
170° F, potentially causing blockage in the cooling passages and leading to engine overheat
and possible damage. Because of these two factors, your outboard operates full-time at
a temperature much lower that your automobile, and requires very different qualities in
its lubricating oil. Yamalube marine oils have detergents, dispersants and viscosity index
improvers to meet these marine-specific challenges head-on.
4
22
4M for
®
2M
®
The typical loads placed on your outboard are much heavier than on your
Your outboard operates at a much higher RPM than your automobile's engine.
Outboards are cooled using raw water, which is often cool to very
Operating environment.
•
sucking in very humid air directly off the water's surface in order to
operate. This humid air also gets inside combustion chambers through
open valves when it's not in use. And in a saltwater environment, that
air is even more corrosive. It's one of the harshest environments
imaginable for an engine. Yamalube 4M and 2M are purposely
formulated with special anti-corrosion agents to help combat
and prevent the corrosive effects of this environment.
Yamalube outboard engine oils provide specific protection other
oils don't, using a proprietary blend of marine-specific anti-wear
additives, shear-stable polymers, corrosion inhibitors, detergents,
dispersants and viscosity index improvers. In short, they're far
superior to automotive engine oils in their strength of protection,
durability and corrosion resistance.
Your outboard is constantly near water,
Scan to see a video about
choosing engine oil.*