Your petrol engine chainsaw uses a fuel mixture. You can prepare it yourself by mixing oil and petrol in the right proportions in a clean, residue-free container, or you can buy pre-mixed alkylate petrol for 2-stroke engines, such as Efco-Mix Alkylate, which keeps for longer than regular mixtures.
Using quality ingredients for the mixture makes your chainsaw engine run better and extends its life (the same applies to all 2-stroke gardening tools). Let's find out why!
We’ll start with the oil. Its function is to lubricate the mechanical components of the engine so that friction is minimised, and to dissipate the heat that builds up. If there is insufficient oil or it has low viscosity and loses its lubricating capacity at high temperatures, the moving metal parts cause friction, wear and can even jam due to the effect of the heat, which causes them to expand. This is typically the case with the piston and cylinder, which can cause engine seizure.
To avoid a seized engine and other inconveniences, choose a quality oil. In particular, you need an oil with good anti-friction properties and, very importantly, one that provides constant viscosity as the temperature changes.
Which oil should you use for chainsaw mixture? Mixture oils consist of a mineral or synthetic base and additives such as detergents, viscosity improvers, antioxidants and so on. You can buy traditional mineral oils, synthetic oils such as Eurosint 2 EVO (which offers better performance in terms of wear, fuel consumption and operating performance) or semi-synthetic oils (containing a mix of synthetic and mineral oil) such as Prosint 2 EVO.
To find out which oil to use for your chainsaw mixture, check the manufacturer’s recommended specifications in the user and maintenance manual. For example, Efco petrol engine chainsaws require 2% (1:50) 2-stroke engine oil: for each litre of petrol, add 20 ml (or cc) of high quality engine oil such as Eurosint 2 EVO, Prosint 2 EVO or equivalent oil from another brand that meets the JASO FD or ISO L-EGD specification.
If in doubt, ask a professional: your nearest Efco dealer is on hand to offer expert advice. We recommend that you don’t use oil for cars or outboard engines.
In addition to oil, fuel mixture for gardening tools includes automotive unleaded petrol. For example, Efco petrol engine chainsaws run on unleaded petrol with an octane rating of 89 or higher. So, you can use petrol from filling station pumps, which has a 95 octane rating and contains up to 10% ethanol (E10 petrol).
Use fresh petrol: Don't buy more than you are likely to use within a couple of months, and keep it in a clean, approved container that is airtight and stored in a cool place, away from direct sunlight. Petrol actually degrades over time: the volatile components evaporate, the heavier components settle and the octane rating falls (which can adversely affect the combustion process). For that reason, don’t use old mixture, and prepare just enough to get the job done, so that it won't be left in the container or tank for too long. Last but not least, at the end of the season or before putting your chainsaw in storage for an extended period, empty the mixture tank.
Did you know that you can stabilise petrol and mixture with special fuel additives, such as Additix 2000 EVO? It prevents fuel degradation for up to one year.
Oil and petrol must be mixed in the correct proportions. A mixture with too much oil will leave carbon deposits on the spark plug and other engine components: here's how to carry out spark plug maintenance. And here you can find instructions on how to clean a petrol engine chainsaw, which is a basic necessity for optimal carburation). In addition, for a perfect cut, read our article on how to keep the guide bar and chain in top condition.
Of course, not all chainsaws are powered by petrol engines: choose the type of power supply that's right for you.