[MichaelWater]

I've had an ongoing "air in the fuel problem" with my 84 300d that i've posted several times about. My latest update is that I have algae, or fungus, in my fuel tank. I think the added pressure caused by the translucent fuel filter being filled with algae is causing air to be drawn into the line from somewhere.

I removed my fuel tank today, & confirmed that about 90% of the inside surface area is covered with fungus. The pre-screen was somewhat clogged with it, but not that bad.

So my question is- what is the best way to get it out? I've already purchased 16 oz. of biobor, but I think that only kills it, leaving the black carcasses to continuously clog filters for the foreseeable future. I currently have about 1/2 gallon of gasoline soaking at the bottom of the tank. I've heard people talk about using alcohol, but do I actually have to go in with a giant wirebrush & scrape every square inch, or is there a magic liquid that will "dissolve" the fungus? I'd appreciate any thoughts on any aspect of my problem.

 

[jdc1244]

Well, yours is one of the more revolting threads in a while…

No, just keep dumping stuff in to kill the fungus and hose it out. Repeat.

I know of an owner who rented a pressure washer. Put the wand-type nozzle up in the tank and blasted away.

 

[mercwagon]

wow, sounds like a scary issue..is this common? (new to diesels)..and what do we do to prevent it from happening? this is off topic of ur exact problem..but i once restored an old winnebago..the sadle tank was severly rusty inside, almost looked like mud and sludge..took the tank out..filled half way w/ water and nuts and bolts..peices of chain..basicaly anything i could find laying around..then capped the ends and rolled it around the backyard..tumbled it for as long as i could..then actually strapped it to my tractor rear wheel and tumbled it some more..after flushing it several times, believe it or not it came out perfectly clean..i was dealing w/ rust..im thinking? that urs might not need as much effort? have also done the same thing to a volvo p1800 fuel tank..but it was just the bottom of the tank that was nasty..we filled it w/ nuts and bolts,pea-stone and water. then strapped it to a kids pull wagon..feet on front of wagon..hands on handle and just shove it back and forth..again the sloshing broke up all the rust and sludge....hope this helps? rob

 

[Gregs300CD]

There's an enzyme additive that actually "eats" the fungus, so you don't need to do anything but pour it into the tank. (Startron, or Star... something or other.)

Since you have your tank out, you can also swish some acetone around inside. If you live where they have the waxy diesel, acetone will help remove any build-up.

 

[jdc1244]

It’s not overly common but it happens enough to be an issue. I’ve always used the above fungicides and the like along with fuel treatment once in a while (L/M Hi-Test). Seems to happen more often to cars that sit for a while or are underused where a layer of water can collect undisturbed. Another good reason to drive your cars often.

 

[cazart]

Is this what the tank screen looks like?

 

[MikeWater]

Just to bring closure to this thread, it was indeed the algae that caused my problem. A tank cleaning with high pressure soap & water at the local car wash, and a few Biobor treatments have kept me on the road problem free for a good 2 months now. Thanks to all who contributed!
Mike