Diesel engines power and feed the world. They are the workhorses of agriculture and the throbbing hearts of heavy-duty equipment and electric generators. Whatever your engine’s application, its fuel system needs maintenance to perform efficiently and to prevent unnecessary downtime.
Diesel fuel is produced from crude oil. A 42-gallon barrel of crude oil produces 11-12 gallons of diesel fuel. Diesel fuel is supplemented at the refinery with necessary additives to improve fuel quality to achieve minimum regulatory specs. A large selection of additives is also available on store shelves. Are store-bought additives necessary? Yes, some additives are useful for achieving optimum power and efficiency from your diesel engine. Additionally, fuel system component life can be extended with proper additives.
Performing scheduled routine maintenance is the first thing you must do to keep your diesel engine in top shape. Using a good diesel fuel additive is the next best thing to do. What are some of these additives, and how can they enhance your engine’s performance?
Cetane Boosters
Cetane is a chemical component of diesel fuel. It is easily ignited with only a small amount of heat. The cetane number of diesel fuel indicates the cetane content in the fuel. In the U.S., federal regulations mandate a cetane number of no less than 40, whereas European governments require a minimum of 51. Higher cetane levels have definite benefits:
- Higher cetane levels reduce ignition delay time, making engines easier to start, especially in cold weather. Your engine will also warm up faster.
- Higher levels improve diesel fuel combustion, producing less soot to foul injectors and compromise engine performance.
- Improved combustion also results in better fuel economy and fewer carbon emissions.
A low cetane number results in delayed ignition, more engine noise, greater fuel consumption, and white smoke emissions.
A cetane booster increases the cetane number of your fuel, giving you added performance. You’ll also gain added engine protection since cetane boosters often contain lubricants that reduce wear. Be sure to check the ingredients of any cetane booster additive. Products made from petroleum distillates are always safe to use. Do not use additives that contain alcohol or harmful solvents.
Fuel Stabilizers
Stored diesel fuel degrades over time due to weather changes and sediment buildup in the tank. In fact, #2 diesel fuel has a storage life of only six months. That’s important to remember because the fuel used in standby generators can sit in a tank for months before it is consumed. Fuel stabilizers help to prevent sediment buildups and make diesel fuel more tolerant of temperature changes.
Fuel Injector Detergents
Over time, carbon can build up on the fuel injectors. This is called coking, and it can lead to fuel injector failure. Coking has several causes:
- High pressure in the fuel injection system produces heat that breaks down diesel fuel and forms soot on the injectors.
- Deposits can build up when an engine is shut down and fuel remains in the injector tips. Because the injectors are still hot from use, the fuel cooks and forms carbon deposits which eventually clog injectors.
Keep fuel injectors clean with detergent additives so they work properly.
Anti-Gel Additives
Diesel fuel naturally contains wax. Under normal conditions, the wax increases the cetane number and gives greater fuel efficiency. But when temperatures drop in the winter, the wax crystallizes, turning the fuel into a gel-like substance. When temperatures drop below 32℉, add anti-gel additive to your fuel and then top off your tank to ensure good mixing of the additive with the fuel.
Corrosion & “Diesel Algae” Inhibitors
Water-induced problems
Water contamination in diesel fuel creates havoc in any engine. Unfortunately, there are ways that water can creep into your system:
- Is there a problem with the fuel delivery system?
- Is there a problem with your storage system? Water can enter the fuel tank through a damaged gauge or an open tank cap.
- Are weather changes causing excess condensation in the fuel tank?
Any water in diesel fuel corrodes metal parts in the fuel system. Corrosion inhibitors create a protective barrier film on metal surfaces in an engine to prevent corrosion.
Water in diesel fuel also promotes bacteria and mold growth. These microorganisms are sometimes called “diesel algae.” Fuel and water separate, and microorganisms can thrive between these two layers, surviving in the water and feeding on the organic components of the fuel. Some fuel additives kill these microorganisms. They also enable the water and fuel to mix so the water vaporizes in the combustion process. Of course, keeping water out of the fuel system altogether is the best possible solution for a diesel algae problem.
Filters can also help with the water removal process in diesel. Fuel filter/water separators remove particle contaminants and contain moisture-absorbing media that can remove almost 100% of water contamination before it reaches the fuel pump and injectors. This prolongs the life of your fuel injection system and prevents breakdowns. In extreme cases of water contamination, a water-absorbent sock may be used inside a diesel fuel tank.
A “healthy” fuel delivery system is critical to the optimum function of your diesel engine. Even though your engine will run on fuel straight from the refinery, using the proper fuel additives will improve the performance and longevity of your diesel engine. HooverTec will gladly answer any of your questions about fuel additives and provide the products you need for peak engine performance.