First, the technical distinction. 2.3hp 4 Stroke Outboard Motor For Honda, like the engine in the car in your driveway, burn straight gasoline within cylinders, circulating lubricating oil through a separate system. Oil and gas don't mix, unless there's a breakdown. Two-stroke engines, in contrast, burn a blend of gas and oil.
Traditional 2 Stroke 5hp Outboard Motor were fed their oil-gas mix fuel by carburetor or injector into the cylinder through an intake valve. During part of this feeding, the exhaust valve was also open, and up to 30 percent of the fuel escaped unburned.
Jump ahead to two-stroke direct-fuel-injection (DFI) engines. The fuel is sprayed into the cylinder with precision timing while the piston covers the exhaust valve. There's no loss of fuel. (In four-stroke engines, thanks to their four piston strokes per cycle, intake and exhaust take place at separate times.) DFI two-strokes and four-strokes both deliver much better fuel economy than traditional two-strokes, since they're directed by computer and burn virtually all of the fuel.
Evinrude's E-TEC two-stroke DFI engines inject fuel twice as fast as standard direct injection, even adjusting the fuel delivery and oil-gas mix as needed. We've tested the E-TEC engines, and they're just as smooth and almost as quiet as four-strokes while maintaining more traditional two-stroke power.
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