Asked by: Rod Heap, Upminster
Petrol goes ‘stale’ more quickly than diesel – impurities and condensation in the tank can cause the fuel to go slimy if you leave it for more than a couple of months. But because diesel is less refined and more oily, it can last quite happily for a couple of years. Chemical stabilisers are available for helping preserve fuel if you’re storing your car or lawnmower for long periods.
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