Avoiding Quality Issues in Diesel Fuel

Diesel and gas fuel tanks. (Courtesy: Jamie Bick at flickr.com)

Diesel and gas fuel tanks.
(Courtesy: Jamie Bick at flickr.com)

Although diesel is one of the most popular fuels for working a forklift, the fuel can degrade over time. If you don’t take precautions to assure that the diesel fuel you use in your forklifts is good, then you might experience a number of problems including:

· Poor engine performance
· Poor starting
· Higher fuel consumption
· Excessive black smoke
· Unpleasant smell from exhaust
· More frequent filter changes
· Clogged and slimy filters
· Corroded or pitted fuel system components
· Sludge in fuel tanks

Over time the chemical nature of stored diesel fuel changes. This causes the creation of solid materials that form slime on surfaces and sludge at the bottom of fuel tanks. Moreover, some diesel fuels include a lot of water that can cause the growth of bacteria that speeds the chemical degradation.

The simple act of exposing diesel to air causes chemical changes. This starts off a chain reaction that causes the development of more undesirable molecules and solid breakdown products. These breakdown products cause blockages and corrosion. These problems can arise if it is common for your warehouse to store diesel for as long as just a few months or even sooner if water and microbes are present.

In addition, leaks in diesel storage tanks and absorption of moisture from the atmosphere can cause the fuel to become “wet.” The addition of more water can cause damage to some engine components and can adversely affect fuel combustion and the lubricating effects of the fuel causing damage to the engine due to excessive wear. Water in diesel fuel stored in tanks can cause corrosion that can add to even more contamination.

Bacteria, fungi and yeasts love diesel because it is an organic substance and provides them with food. Whether the microbes are introduced through the air, through moisture or from already contaminated supplies, they can multiply quickly. The acidic byproducts of the microbes and the slime created by their biomass and fuel breakdown can present all sorts of dangers to a forklift engine. All of this stuff can collect on surfaces and in pits and crevices where major corrosive damage can occur.

The slime and sludge goes through the fuel system and on to the engine and block filters and fuel lines. The acids that come from the slime and sludge damage engines, fuel systems, storage tanks and other vulnerable surfaces that come in contact with it.

Besides the microbes that appear due to chemical changes and the introduction of water, other contaminates can affect diesel engines including rust, dirt and sand.

Many European countries are now blending biodiesel or biologically produced diesel into diesel fuel to improve lubrication. However, biodiesel breaks down faster, absorbs more water and is more accommodating to microbes. So because of the use of biodiesel forklift managers must take extra precautions to protect their fuel from contamination.

How to Prevent Problems Due to Bad Diesel

To prevent problems, it is encouraged that you purchase your diesel fuel from a reputable supplier and store it in well-maintained tanks that don’t leak.

Be aware that the fuel filter in your forklift is not sufficient for completely preventing issues due to bad diesel. It is up to you to be sure that the fuel you use is clean and in good condition. To help assure cleaner fuel you can store diesel at lower temperatures including below 70°F or 21°C and use fuel stabilizers, biocides and other treatments to help extend the life of the fuel.

Regularly check the diesel fuel storage tanks for defects that could result in diesel leakage out of or water leakage into the tank. Commonly, the space between the fuel and the top of the tank is taken up by air. This can be a source of moisture. So keep that down to a minimum. Keep only enough space at the top of the tank that can accommodate the expansion of the fuel. Topping the tank off with fresh diesel is a good way to keep the amount of air in the tank to a minimum.

There are a variety of fuel stabilizers available that can be purchased and used if you have to store a supply of diesel for relatively long periods of time. You should use test kits to monitor the tank regularly for water and microbial contamination in the fuel.

Another action you can take to reduce contamination is to use a filter whenever you move diesel fuel from one storage tank to another.

If microbes are contaminating the fuel, use a large dose of biocide to kill them. Be sure that you filter the dead microbes and the solid materials they create out of the fuel and clean the tank thoroughly.

Use a filter when putting fuel into the forklift and perform this activity in a dry, dirt-free environment.

Consult with specialists about preventing contamination if you store diesel fuel for long periods of time. They can also provide you with automatic systems for cleaning and removing solids, water and microbes.

About Robert J