article header chainsaw cutting log
  • Ethanol is an alcohol which is produced through the fermentation of vegetable matter
  • Australian Fuel Quality Standards for ethanol content in fuel is generally limited to 10%
  • In Australia fuel containing Ethanol is often referred to as E10
  • Fuel purchased for your outdoor power equipment shouldn’t contain more than 10% ethanol.
  • If the petrol pump does not state the ethanol content of the fuel, STIHL recommend asking the petrol station attendant what percentage of ethanol is in the petrol.
  • STIHL advise to take appropriate precautions when using fuel containing 10% ethanol in your STIHL products. For more information please download the complete Fuel guidelines for STIHL Outdoor Power Equipment

Why users should be cautious when using fuel containing Ethanol


STIHL recommend that you always use good quality fuel purchased from a reputable
supplier in your STIHL outdoor power equipment.
When purchasing fuel for your STIHL product, it’s important to keep in mind if the fuel you’re using contains ethanol. Ethanol can dissolve the varnish and gum deposits that may have formed in your fuel can or inside the equipment’s engine. These deposits can become dislodged and can mix in with the fuel, blocking the small openings and filters within the fuel system.

When using petrol outdoor power equipment it’s expected that as the fuel is utilised by the machine. The void left in the tank will be replaced with air. When using fuel containing ethanol it’s important to understand that a characteristic of ethanol is its ability to attract and mix with moisture that may be present in the air entering the tank. This can lead to corrosion of the metal components within the fuel system.

In addition, users of Ethanol fuels should keep in mind that in the event that enough water is absorbed, it can cause the ethanol and water to separate from the petrol blend and settle at the bottom of the fuel tank. This can result in a layer of petrol left floating on top, which has a lower octane level than the original ethanol petrol blend that was originally used to fill the fuel tank. If this happens this can result in unstable engine operation, loss of power and major engine failures.

Guidelines for using E10 fuel in STIHL outdoor power equipment


If the proper precautions are taken, fuel containing 10% ethanol can safely be used in your STIHL products.

  • STIHL recommend to always use fresh fuel that has a minimum of 91 octane petrol.
  • Petrol has a shelf life of about 30 days so it’s important to only purchase petrol that can be used within that timeframe.
  • Consider using a pre-mixed alternative such as STIHL MotoMix®. MotoMix® is a specially formulated fuel mixture that is a high-grade, high-octane, ethanol-free premixed fuel containing STIHL HP Ultra synthetic oil. STIHL MotoMix® fuel mixture is both pure and stable and can be stored for at least two years in the original container, making it ideal for machines that are used infrequently.
  • Always store your equipment properly. For equipment that is used infrequently, it’s recommended that the remaining petrol in the machine is drained from the tank and disposed of properly. To make sure that any remaining ethanol is removed from your equipment, STIHL recommends adding a small amount of STIHL MotoMix® Premixed Fuel to the tank and running the engine for a few minutes to circulate the fuel throughout the fuel system.
  • Finally, equipment should be serviced regularly by your local STIHL dealer. Items such as fuel filters, fuel lines, carburettor diaphragms and spark plugs should be checked and replaced if necessary as part of general maintenance and care. For more specific model maintenance and care requirements, refer to your owner’s manual.

For more information about fuels in your STIHL products please download the complete guide below.