Posts: 3480
Location: Elk River, Minnesota | Hiya,
Agree with Steve Worrall here. E10 has been around for a long time and so have 4 stroke outboards now. They have been built to meet clean air requirements and will run very well and very cleanly.
Mechanically, the engines as Steve mentioned are the same...injection systems are the up and coming systems that will be changing in 4 stroke technology as we are seeing with direct injection on automobiles...it is only a matter of time before that technology will come to outboards. At that point, there will be some issues to deal with, but it will NOT be due to E10 fuel...it will have to do with how the crankcase is equalized for pressure.
Example: New Direct injection systems inject fuel directly into the combustion chamber bypassing the intake valves. These engines then have to have the pressure equalized through the PCV system, which sends crankcase air back to the combustion chamber...which goes directly through the valve train system. The air coming through will carry oil vapors, which over time will cake onto the valves (called "coking"). This happens because there is no fuel flowing over the intake valves to essentially "wash" them off. Inevitably, this will lead to a tear down of the valve train to scrub and clean, unless there is a "catch can" system in place to significantly reduce oil vapors.
Currently, I don't believe this is an issue at this point...
No matter what your owners manual recommends, E10 is THE way to go...for clean burning, clean running engine.
Steve |