How does a four-stroke premix and fuel engine work?

Four-stroke premix engines combine a four-cycle engine design with the lubrication elements of a two-stroke.

As the name implies, four-stroke premix engines go through a four-stroke combustion process (intake, compression, power and exhaust) to produce energy but are lubricated by an oil and fuel mixture instead of oil alone.

Benefits of the design:

High-fuel efficiency and fewer emissions
Easy maintenance with the use of the standard fuel-oil premix
Improved lightweight, compact construction
Ability to operate at various angles
Excellent acceleration, delivering impressive lugging power and higher torque
No extreme sound levels, even at the highest power

Lubrication considerations

While four-stroke premix engines provide unique benefits, they also bring unique lubrication challenges.
Specifically, ash control is critical as the oil and fuel mixture passes through the engine valves. Too much ash can lead to deposit formation that can cause poor performance, excess heat that can damage engine components, or worse, engine failure.

How it Works - Four-Stroke Premix Oil and Fuel Engines