Fuel System Additives – Are they really needed?
If you’ve brought your car to a quick lube franchise in the past year you’ve probably heard the sales pitch for treating your fuel tank with an additive. The argument the technician will use is that the ethanol additives in today’s fuel will gum up your untreated fuel system. And if you’ve talked to your mechanic, you will hear about carburetors that have crystal formations inside them that clog valves and jets. So, when do these problems appear in fuel systems? It comes down to consumption and how the fuel is stored. A fuel system that has frequent turnover of gas/diesel should not have a problem. Fiberglass and polyethylene tanks that are kept full for less than 1 year are not likely to develop issues. It’s the fuel stored in partially filled steel tanks that are at risk. Water that condenses inside the cool tank will fall to the bottom of the fuel. The organic matter in the fuel will separate and settle there. The combination of water, steel, and organics provides a breeding ground for algae, bacteria, and fungi. Based on the calls we’ve received to clean tanks, pump out bad fuel and remove clogged filters this issue is more common than most customers realize.
So, do additives really prevent this from happening? It depends on the targeted bacteria, yeast, or algae, and the level of contamination. If you treat an uncontaminated diesel system with a preventative dose of biocide, it will prevent new bacteria from growing in the diesel fuel. According to a Dow® Chemical study, fuel systems that were heavily contaminated required multiple “shock” treatments to bring the bacteria levels down. If you are just treating for ethanol separation and crystallization, most additives will help. Because ethanol is produced from a plant-based source it will attract water more readily than fossil fuels. We recommend an additive that contains both a corrosion inhibitor and biocide. Corrosion inhibitors are designed to evaporate water and prevent varnish and pitting. Biocides prevent algae, bacteria and fungi from growing on the water/ethanol layer.
Another method to determine your fuel tanks health is to test the tank regularly. If you check the PH of the water removed from the tank bottom, the levels should be in the 6 to 8 range. A lower PH level will indicate higher acidity levels and an increased corrosion risk. You can also put a sacrificial piece of metal in your fuel filter to provide an early warning of corrosion. A polished washer made of the same material as the fuel tank should never change appearance when stored in good fuel.