Fuel Contamination 5.9 or 6.7 Need Answers

[RBellah]

Need some real good advice from the pro's here. How can water or fuel contamination get past the filter? Assuming the filter has been changed according to the recommended service. I hear about this and it usually starts out the owner takes truck to Dealer and they dealer drops tank and find muck in the tank. Then they advise the customer to call their Insurance Company. Per Dealers the system needs to be changed out from the fuel pump in the tank all the way to the injectors. Is there any data from Cummins to support the changing of the injectors due to fuel contamination? Up to the filter would be expected and a clogged filter too; but, pumps, tubes and injectors? Give me some explanation if you can... . Thanks in advance.

 

[sag2]

First of all, it may not just be water. It can be anything from water, algae, gas, sugar, corrosive liquid etc.

Lets assume it's water based (might include algae). If the owner has been using an additive that helps to remove water, it picks it up and passes it right through the filter. If not, once the filter gets loaded and you continue to run it, the filter will allow the water and debris to also pass through the media. Once past the media the corrosion starts in anything ferrous. The flakes grow, break off and pass through the system. Also if the pump gets the corrosion and it damages the pump, the debris from the pump goes into the rail and injectors and ruins them. It kind of snow balls as you can imagine.

Most of the problems are caused by lack of maintenance of the filter, or just overloading the filter capacity with a really bad load of fuel.

 

[fritzcartage]

i talked to fleetguard/cummins and they said that with the low sulfur diesel they have seen asphalting of fuel



when a truck idles or runs the hot fuel that is unburned travels back to the tank and reacts with the cold fuel in the tank



that may be the problem your referring to

 

[jelag]

water can emulsify and form tiny droplets and blend with other chemicals, once this occurs it can pass some filters...

In most cases, large class 8 trucks have a primary filter of 10 micron with a water trap and a secondary filter of 2 microns... that's what we've installed on all our trucks... the large 10 micron filter holds enough fuel and it moves slowly through that filter, with some luck, the water droplets fall out of suspension and to the bottom of the filter where they can be drained...

We look at our primary filters every 6 months or so, and really never find more than a teaspoon of water... we changes both filters every 50-60 K miles... we let a set go on our 08 5500 and they ran 105K miles before they clogged enough to through a code in the computer... both were clogged with dirt...

On the 08 when we changed the filter we also checked the factory filter and changed it. . at that time the 08 had 110K miles and factory filter had no water contamination and to be honest had not been checked from when we took delivery. .

We never buy fuel in a station, we only buy fuel in a card lock and I don't think I've ever been to one where each hose wasn't protected with a large filter... usually they date them with a black marker and change them. . its my personal opinion that most gas stations don't have a clue how to maintain diesel in tanks nor care for the delivery process...

The trucks I currently have running have over 1 million total miles without fuel contamination, and we get fuel in at least 40 different spots over the course of a year... remember though they are all card locks or truck stops...

I suggest you consider the cost benefits of additional filtration on the frame and the peace of mind that provides... for us and our trucks, knowing on any given day one might be 500 or more miles from the shop and buying fuel in a card lock we've not been to in 5 months, the peace of mind is priceless...

Hope this helps.

 

[Wingate]

Contamination can be several different things... Something as simple as dirt from an improperly maintained nozzle can load a filter... not sure if I agree that a filter gets loaded then starts allowing dirt thru. The filter should basically starve the engine for fuel rather than let it pass. If theres a bypass somewhere in my filter base, I want to find it so I can remove it!!. but the conventional filter manufacturers seem to be falling behind in developing a filter to protect against bio- blends. there are many different chemicals that can pass right thru the filter that can destroy your fuel system... . remember, the only requirement is that the chemical have the ability to pass thru a 7 micron filter media.

On the other hand, I have personally witnessed dealerships use this as a crutch to cover poor troubleshooting procedures and less than honest business practices to milk an owner of alot of $$$$$$. .

 

[RBellah]

TDR has a great source of information and a lot of great people. I appreciate the honest replies to this fuel contamination question... . there must be somebody who can do a TDR article on this with possibly the right person for these answers? It may appear to be a broad question; but it maybe because most fuel contamination issues are not a one time event... . possibly several events to cause the problems down the line past the filter IE injectors, tubes etc.