A nasty brown or black sludge is a key indicator that water contamination in your diesel fuel has got to the next stage in causing a problem for you.
If you think your diesel has been contaminated with water, some telltale signs to watch for include: A loss of RPM and power in the machine. Rough starting or erratic idling. Trouble or a lag in acceleration when stepping on the pedal.
Just like oil and water, diesel and water don't mix – they separate. So, if there's water in your tank, it settles to the bottom. That water will cause your tank to rust and algae to grow.
Let the fuel sit in a clear container and in a dark place for about 24 hours. Water is denser than diesel, so if it is present then it will sink to the bottom of the container.
Diesel fuel contamination also forms biomass (accumulation of microbial cells), which may look like a thick, slimy material. Biomass can be present even when you are unable to see it. Biomass can obstruct engine mechanisms so that the engine works less effectively—or even stops working.
Symptoms of Dirty Diesel Fuel
The outward symptoms of these are pretty straight forward. You'll get lower fuel efficiency. Hesitation upon acceleration and rough idling. You'll also get higher levels of certain kinds of emissions, though those will be caught by the emissions control system.
Black mud will nearly certainly specify diesel bacteria contamination. Look for traces of black sludge in the old fuel filters when you're changing the filters on the fuel tank. If your fuel tank has a drain tap, then pour some into a glass or a clear plastic container.
The EN590 specification includes multiple characteristics but water contamination is the biggest factor for causing problems. EN590 states a maximum of 200mg of water per kilogram of diesel fuel. That's 200 PPM.
all these diesel cars have this fuel filter. and most of the mechanics don't even know this but uh the diesel filter of your car does not only filters the diesel but it also separates the water from the diesel.
Diesel engines produce water when hot fuel from the injectors is returned to the fuel tank; this produces water from condensation, which settles under the fuel.
Diesel Extreme is the best additive in the game. This one adds seven points to diesel's cetane score (which again improves the fuel's combustion performance), and it cleans and lubricates injectors and other critical fuel system components. Diesel Extreme also helps remove excess water and contaminants from fuel.
Test your diesel fuel for contamination. Simply dip a 4-in-1 test swab in your fuel tank and check the test chart to determine fuel quality and the presence of contamination (water, rust, sludge/asphaltenes).
Water is commonly found in diesel fuel due to condensation, handling and environmental conditions. Diesel fuel tanks are always subject to water condensation because diesel fuel, unlike gasoline, has no vapor pressure to displace air.
Removing any water as soon as possible is necessary because diesel and water do not mix, causing the water to settle at the bottom of the tank. If it remains, your tank can rust and algae can grow, causing damage to the engine and its parts.
“Diesel fuel containing low levels of dissolved water, in the ppm concentration range, will typically provide satisfactory service,” says Harvey. “However, free water in diesel fuel could result in excessive injector wear, filter plugging, power loss and corrosion of engine fuel system parts.”
Emulsified water - Under pressure changes, agitation and heavy cavitation, often experienced as the fuel passes through pumps and filters, the water content can become completely emulsified turning it from cloudy to milky diesel fuel.
Wax. Wax build up, or gelling, occurs when the paraffin wax in diesel fuel solidifies because of a drop in temperature. When cold soaked, the paraffin wax present in diesel solidifies, giving the fuel a cloudy appearance.
Gelled Fuel in The Fuel Tank:
Remove the fuel filters and fill all fuel filters with a mixture of 50% Diesel Winter Rescue and 50% diesel fuel. Reinstall the fuel filters and then start your engine. Let your engine idle to warm up the fuel system and clear any remaining gelled masses.
A diesel fuel biocide. This dual-phased (effective in both diesel fuel and water) biocide kills microbes in fuel, including bacteria and fungus. Use this product to rid your fuel system of microbial contamination.
The first signs will be small black specks in your clear pre-filters. To find out how bad it is, you have to inspect inside your fuel tank. That can best be done by removing the fuel sending unit. If it is all black like you see in this picture you probably have algae growth in your tank.
Tank contamination known as diesel sludge is an algae-like substance in which cells adhere to each other on the tank surface or at the fuel water interface. The sludge settles to the bottom of a fuel tank and can clog filters when the vehicle is fueled.
All diesel fuel can be cleaned and made back into good useable fuel. Do not use fuel that is not clear in color. It should be amber or red in color.
But another problem is so-called 'dirty' - or contaminated - fuel. There have been reports that dirty diesel can have such an adverse effect that it can damage injectors or actually destroy an engine, costing the owner thousands of dollars.
Diesel smells bad because of its high sulfur content. Diesel has 15 mg/L of sulfur which typically smells like a combination of skunk, rotten eggs, and burnt matches.