Fuel System Problem

[jbNova]

Looking for some advice on what maybe happened and the best route to take from here about a problem I found when changing fuel filters. The truck is a 2018 that doesn't get driven much (about 19k miles on it) but usually longer trips when it does, and has always had either Schaeffer's Diesel Treat 2000 or SoyShield added when filling up. This filter pair has been on the truck for about 11k miles and 4 years.

The truck was driven the day before the filters were removed and seemed to run pretty normal, so I'm assuming that the front filter has done its job and nothing made it to the CP3/injectors. However, I'm undecided on what to do from here...clearly have a corrosion and/or contamination issue, but not sure if I should just change the rear filter head and keep leaning on the filters to catch anything (seems risky) or if I should be dropping the tank/changing fuel lines/etc. The truck is out of warranty so non-OEM parts and solutions are fine if that's the best route forward.

Not a great picture, but there was definitely some scale in the front fuel filter (bottom of the pleats there).

This was after "cleaning" (wiping with towel) the fitting on the rear filter head. The scale was rust colored and when I lifted the check valve ball with the towel up there, some small flakes or splinters would come back with the towel.

Thanks

 

[Topzide]

You've had some water in your fuel tank! Could be from not being driven that much. Is the truck garaged? Is the fuel tank kept full? Temp changes create condensation that will form in both the fuel tank and the DEF tank. If you do all of the above, you got some bad fuel somewhere. Have you been draining the water drain on the rear filter? I check mine at least once a month.

 

[Grumpy8811]

I would not do anything but replace the filters and continue motoring.
I might drain the water separator into a clear bottle a couple times over the next couple months, just to make sure you captured most of the water. ( you probably did)

 

[Ozymandias]

I second this, also don't run bio-fuel in vehicle that is driven so little and sits most of the time. Every bio comes with some H²0 content, bio always also means bio-degradable.

 

[Grumpy8811]

diesel fuel is hygroscopic.. in other words it absorbs water from the air, all by itself. Good thing is these trucks have an under truck water separator which should collect water first, and a WIF light should illuminate if you actually have enough accumulation to be noticeable..

 

[jbNova]

You've had some water in your fuel tank! Could be from not being driven that much. Is the truck garaged? Is the fuel tank kept full? Temp changes create condensation that will form in both the fuel tank and the DEF tank. If you do all of the above, you got some bad fuel somewhere. Have you been draining the water drain on the rear filter? I check mine at least once a month.

The truck does stay in the garage (but non-climate controlled...in Texas).

The fuel tank is not usually kept full and I have not been draining the fuel filters at all. I guess I had a little too much confidence in the water-in-fuel sensors to tell me if something needed attention.

The fuel I drained out of the rear separator before removing it looked clean and clear though, so it doesn't seem like there's currently water in there.

 

[Ozymandias]

Tank is sealed, it isn't breathing at night like in the old days.
There are valves that regulate the inside pressure/vacuum.