Fuel for Thought
with Raffaele Saccoccio from ES Motors Moortown
The introduction of a new type of petrol in the UK, E10, may create some extra costs for owners of older cars, but the aim is to reduce carbon dioxide emissions. E10 is made up of 90% regular unleaded petrol and 10% ethanol. It is possible to run cars on pure ethanol, as has been done in Brazil for decades, but here it is blended with fuel derived from oil to prevent engine knocking and enhance a car’s performance.
The government argues that the use of E10 petrol is an environmental move to reduce emissions, a shift equivalent to taking 350,000 cars off the road. It’s not all good news though. As a fuel, E10 is slightly less energy dense, meaning it could reduce the miles per gallon your car achieves by up to 1%. What’s not widely known is that since 2016 new cars have been certified for emissions and performance using E10, so when you bought a car and were told how many miles to the gallon it would do, that number was already based on using this new fuel.
All cars registered since 2011 are required to be E10 compatible, so the potential issues arise for owners of older and classic cars. While the government has provided an online E10 checker as an easy means of finding out if your car copes well with E10, the RAC estimates as many as 600,000 vehicles on UK roads aren’t compatible. Drivers of cars registered prior to 2002 are advised not to use E10 in their vehicles, as problems have been reported.
If you put the fuel in an incompatible car, it will still run, but seals, plastics and metals may be damaged over longer periods because of ethanol’s corrosive properties. Ethanol is also a hygroscopic – which means it absorbs water from the atmosphere, leading to condensation in fuel tanks if the car remains unused for long periods of time.
In addition to running issues, the Federation of British Historic Vehicle Clubs confirms that the increased acidity, conductivity and chloride content of ethanol in E10 can cause corrosion and tarnishing of metal components (such as carburettors, fuel pumps, and older fuel tanks). While corrosion inhibitor additives can control this, the same cannot be said for its compatibility with seals, flexible pipes and other unsuitable gasket materials.
So what options do owners of traditional classic cars have? Well, the good news is that the technology exists to upgrade the fuel systems to cope. At one extreme, Prince Charles had his beloved Aston Martin DB6 updated to run on bio-E85, a blend of 85% ethanol fuel and 15% gasoline, but at a minimum it is good practice for classic owners to renew ancient fuel lines as a precaution in any case. If you’re looking for a modern fuel hose from a reputable supplier, drop into our garage and we’ll do our best to help.