Can I use petrol left over from last season?

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Regrettably, no. Over time, untreated fuel begins to break down, which leads to hard starting, poor performance or an engine that won’t start at all.

The lightest chemicals evaporate first, leaving a heavier petrol that doesn’t combust properly. The engine will probably still run, just not as well.

A more serious problem is oxidization, which is caused by hydrocarbons in the fuel reacting with oxygen to produce new compounds. This results in gum, which can clog fuel lines and filters and create deposits in the fuel system. Gummed-up carburettors can be expensive to fix and may not run properly until deposits are removed.

Water that finds its way into fuel tanks through condensation caused by fluctuating temperatures can also cause issues.



To avoid future issues with stale fuel, try not to store petrol in tanks or containers for more than 45days. If you know petrol will be sitting for longer than that, add Briggs and Stratton Fuel Fit [link] This will help prevent oxidization! We find most people use traditional 5 litre fuel containers. So after filling up with fresh fuel at the fuel station simply add 50ml of Fuel Fit to your 5 litres of petrol. Give the can a shake and your fuel will stay stabilised for up to 2 years!
Briggs & Stratton Fuel Fit additive is available in 100ml and 250ml bottles and is available from us Remember to order some the next time you need us!