This is quite a poor photo of the bottom of my fuel tank.
Back in the summer I went on a road run and the truck was a bit sluggish, got back and changed the fuel filter, cut it open and it was almost black inside. I was running 2 tanks so decided to blank the 1 and the other had this black oil like
substance like in the photo. Took the tank and fuel lines off and steam cleaned them off and it was running ok again. After probably 200-300 miles it refused to start 1 Saturday. I took the filter off and cut it open and again and its got this black goo in it.
Replaced the fuel filter again and it started ok. As you can see the black goo is back in the tank again. I thought maybe fuel fungus but I always keep it dosed with anti-fungucide. i have been reading about Asphaltenes and wondered if anyone has
had any experience. Normal degreasers don't seem to touch it. Engine is a 743 Cummins and the truck is started most Saturdays and moved outside so we can work on the everyday trucks. Its hobby truck so doesn't do much mileage. Any help
would be appreciated.