4-MIX engine

Lightweight and with good lugging power

The award-winning STIHL four-stroke engine that runs on a petrol-oil mix. The STIHL 4-MIX engine thus combines the advantages of a 2-stroke and a 4-stroke. As well has having plenty of lugging power and perceptibly higher torque, the 4-MIX engine is also convincing in terms of lower emissions, low maintenance and a pleasant sound.

Clear advantages

Fewer emissions: The fuel burns with very little in the way of residues and thus complies with the strict European exhaust emission limits, Stage II.
No oil servicing: Easy maintenance, as it uses the familiar fuel mix.
Lightweight: The mix-lubricated system avoids the need for components like an oil pump, sump and oil tank as on conventional four-strokes.
Lower noise threshold: Pleasant sound, even at high power.
Lugging power and high torque: Very good acceleration for plenty of power.

This is how it works

Unlike other four-strokes, the 4-MIX engine runs on a standard petrol-oil mix (1:50). A completely new feature is that the petrol-oil mix is distributed through the engine via a bypass channel in the cylinder head for complete lubrication.

Easy starting
To make starting the STIHL 4-MIX engine easy the engine has been fitted with a decompression system which extends the valve opening times when starting. That considerably reduces the effort needed to pull the starter rope.

Lightweight for easy servicing

Its mix-lubricated fuel system makes the STIHL 4-MIX engine lightweight. Components like an oil pump, oil tank and sump normally needed with conventional four-strokes are not required with the 4-MIX engine. Fiddly chores like regularly adjusting the valve play, checking the oil level, changing the oil and disposing of waste oil are thus a thing of the past.