Black debris in fuel filter 1 day after replacement.

[Zoltan]

I just replaced the fuel filter (the small one that is attached to the firewall and also called "fuel strainer" by Nissan) yesterday and I already have small amount of black "dust" sitting in the bottom of the bottle.
The old one looked like it had this black stuff covering the walls all around. When I shook the old strainer, some of the black stuff came loose and made a "dust" cloud.

Any ideas what it could be?

I suspect the rubber fuel lines are breaking down and contaminating the system and the dust is just microscopic pieces of rubber. Did any one have similar experience?

[philip]

I just replaced the fuel filter (the small one that is attached to the firewall and also called "fuel strainer" by Nissan) yesterday and I already have small amount of black "dust" sitting in the bottom of the bottle.

First, I hope you are using the fuel 'strainer' instead of a fuel "filter." See the thread titled "Fuel Filters."

My truck experienced a similar situation not long after the first use of B100 biodiesel. And long since the last B100 and B20 runs, some little flecks of black colored chips have relocated to the little primary screen. I have drained off about 1/2 gallon of fuel from the fuel tank drain plug but only found debris the first time I did this.

As long as air is not being admitted into the suction side of the Lift Pump, then I'm not concerned. These engines do not purge air very well. Run the truck down to the "Empty" mark or smidge below and you will see what I mean.

[Zoltan]

The stuff I have really looks like dust not chips.

[philip]

The stuff I have really looks like dust not chips.

Is the word "silt" more appropriate?

Have you operated the fuel tank drain plug to remove a couple of quarts of diesel fuel?

[Zoltan]

Yeah, silt that is!
"Naturally", I filled up the tank just before I installed the fuel strainer . Do you recommend to remove some fuel now or wait till it gets down?

Regardless where the silt is coming from, I should replace the fuel lines. Probably they were never replaced, and I can see some cracks inside where they join the metal tubes (and the strainer for that matter). Would any kind do? I mean what Napa sells for gasoline cars, would it work with diesel? I know diesel fuel dissolves some stuff that gasoline wouldn't.

[philip]

Yeah, silt that is!
"Naturally", I filled up the tank just before I installed the fuel strainer . Do you recommend to remove some fuel now or wait till it gets down?

I would allow the vehicle to sit on level ground for at least a half hour, to allow the fuel tank contents to settle down. Then drain off 1-2 quarts. Examine the drained fuel, looking for contaminations. The absolute fuel level is of no consequence right now because the pickup pipe is very close to the bottom of the tank.