E10 Fuel in Your Lawn Mower- What to Be Aware Of

Itโ€™s estimated that the greener fuel could reduce CO2 emissions by 750,000 tonnes per year, the equivalent of taking up to 350,000 cars off the road!

Currently unleaded petrol in the UK contains up to 5% bioethanol known E5The E10 fuel will contain 10% ethanol.

Why is Ethanol bad for your lawnmower engine?

The most critical problems caused by ethanol fuel blends are water contamination and fuel separation, both of which happen during storage. This process is sped up when the fuel is allowed to โ€œbreatheโ€ to the atmosphere and the ethanol is given the chance to absorb moisture from the air. Whilst a small amount of water in the fuel might not cause an issue, if the machine is left in storage for a longer period, the fuel can absorb moisture to a point where it cannot be held in suspension any longer and phase separation will occur. This will appear as a bubble or layer of water which will sit below the fuel in the fuel tank.


This ethanol-water mix is very corrosive and will not allow the engine to run if it is sucked into the fuel system. If this happens within the carburettor of the machine, it can leave behind gummy deposits which can block ports in the carburettor when the fuel evaporates. Sometimes this can be resolved by simply removing the carburettor and giving it a clean but more often than not, a new carburettor may be the only solution.


Use ethanol-free fuel such as Aspen and you will also benefit from reducing toxic emissions and not needing to mix 2-stroke fuel.

If you continue to use regular pump fuel, always keep your fuel fresh, never buy supermarket fuel (this seems to cause more problems) and never use fuel over 30 days old โ€“ whether in the fuel tank or from a storage container.

You can user super unleaded fuel from forecourts which contains 5% ethanol (keep an eye on this) or recommend a fuel called Aspen. Aspen contains no ethanolwill stay fresh for up to 5 years, emits 99% less toxic emissions and ultimately prolongs machinery life.