Black fuel filter(pics included)

The only place I can find it is at the TA in Coachella

 

If you are getting black smoke out the stacks, your oil will soot up and turn black faster because of the unburnt fuel entering the crankcase.
ULSD is prone to having water in it. Can't remember it all, but many of solvents that used to be in diesel are gone and instead of water just passing with fuel in separates more easily and collects in tanks and fuel water separators. We started noticing it badly around 2010. We shock treat our bulk 12,000 gallon tank every quarter with Power Service tank cleaner Clear-Diesel Fuel & Tank Cleaner - Power Service , use power service biocide every half, and put Diesel Klean in every transport load. Has seemed to help .

 

Seen tanks black as a barrel of oil. Injector orings seem to cause it more than fuel pump.

Since 1997 I have change 3 detroit fuel pumps. Not known for failure. One worn out, one external leak. And one on my own truck because I was doing a complete overhaul. But it is possible.

That's algae, alphaltine, or fuel lines coming apart.

If it was combustion you will see bubbles in fuel tank.

 

I would also disassemble Davco and clean housing. Normally you have to order a lower oring ahead of time. That junk will hangout on the bottom if you drain it.

If you add biokleen. Carry spare filters with you for a few weeks.

 

My tanks have bubbles. Very little, small bubble every 4-7seconds. Maybe only 3-4 seen at a time. Is that normal? Or enough to consider a problem?

 

That's a tough call, if it runs fine with no problems I'd keep watching it.

9/10 its going to be very obvious.

But changing orings is cheap and simple.

 

7 years on the fabric they claim. I just changed mine at 8 because I thought I found a small piece in filter. Better to be safe.