October 2021

going to be very low and buying Super Unleaded will certainly be the best option.” Phil added: “The sizeable amount of publicity on the roll- out of E10 is being produced to avoid unaware motorists turning up at the forecourt unsure as to whether their vehicle is compatible. If someone puts some in by mistake, they won’t need to get the tank drained, but the government FAQ answer is to just use the correct grade next time.” Absorption The roll-out has been reasonably smooth so far, but it is when the fuel meets the car parc in the real world that the real trouble might begin. While the government has provided a good level of information, and the industry is directing motorists towards it, the result of when real-world drivers have been filling up with E10 for a while will not be seen for some time. With that 5% of incompatible vehicles, there is a mix of cherished classics driven by informed enthusiasts, as well as a few odd-one-out modern cars where the owner has no clue of the potential impact on their car. Then there are the bottom-end older cars being driven without aesthetic or historical concerns. This is where the problems are most likely to surface. Mike Schlup, MD at Kalimex the distributors of JLM professional fuel additives, explained more. “Food, including alcohol, goes off. Leaving a bottle of wine open causes the ethanol to oxidise, due to its exposure to the air. Similarly, adding bioethanol to petrol ages the fuel faster than petrol made from fossil-fuel alone. Running an engine on expired petrol affects not only fuel consumption but also its reliability. The resultant deposits can also build in the fuel injection, lubrication system and crankcase, all of which affect long-term engine life. “Unlike petrol, bioethanol absorbs moisture. If the water remains suspended in the fuel, when it enters the engine, damage is unlikely. Yet, once a critical level of water becomes absorbed, the water/ethanol mix drops out of the fossil-fuel and falls to the bottom of the tank. Should this be sucked into the fuel injection system, the engine is likely to stop running. This process, known as phase separation, leaves a deteriorated, off-specification, low octane layer of petrol above it, which will not burn within the engine as intended. The phase-separated water/ethanol cocktail beneath it cannot be re-blended into fresh petrol and is best drained, or sucked from the fuel tank.” That’s not all: “Apart from resulting in slightly inferior fuel economy, E10 fuel introduces gum formation and promotes fuel injector deposits. Aside from being corrosive to certain materials, bioethanol lacks any lubrication properties. While this can affect upper engine cylinder and valve longevity, it can also influence the durability of fuel system components, especially the expensive high-pressure fuel pumps, used on older gasoline direct injection (GDI) engines. As ethanol is an effective solvent, E10 is likely to loosen old residues within the fuel tank, which could create a blockage.” Mike went on to say: “Considering that E5 petrol can phase-separate faster than E10, JLM's E10 fuel additive provides most answers to the challenges posed by bioethanol-laced petrol. Its fuel stabilisers ensure that E10 does not age appreciably for at least two months. This helps to maintain the fuel's quality and preserves its octane for longer. Apart from slowing the tendency of the fuel to 10 AFTERMARKET OCTOBER 2021 BIG ISSUE www.aftermarketonline.net E10 is likely to loosen old residues within the fuel tank, which could create a blockage ”