Fuel its dark, filters very dirty....whats the problem?

Looks like fuel algae. Black slimy algae growing in your fuel tank/system. I am not an expert at all, but have heard the best way is to boil and rinse and dry the tanks and lines. Good luck.

 

Go to the search window in the upper right corner,type in " fuel algae "..lots of info.

 

A lot of guys used to dump the old crank case oil into the fuel tanks after an oil change, any possibility the old owner did that?

 

Never heard of dumping your used oil in the fuel tanks what would be the reason for doing that?…........ I would do what the OLDMAN suggest and add a additve to your fuel tanks. That's what I did just can't remember the name of the stuff i used to remove the. algie .

 

Did your parents live through the great depression? Waste not want not. A gallon to each tank every fill up saves you about $7 and cost about $2,000 in electronic injectors next year. Kileem? Carry extra filters, read the posts.

 

Yes it was kileem ...worked great.

 

Simply stating a fact!

 

Go to a marine supply store and get a fuel algecide. They Use It A Lot In boats. That should kill it but carry extra furl filter as the dead algae will clog your fuel filter.

 

If it's a cummins 2009-2013 that is soot and or oil but mainly soot. Those engines are real dirty. Won't hurt anything. Just plugs up the fuel filter a little sooner. If you are wanting to be sure, take a sample of the fuel from the filter and send it out to the lab OPS has a relationship with. They can tell you what is in the fuel.