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Flay_Crosswell's avatar
Mar 09, 2016

Algae in fuel

I have a 98 tradition w/300 cummins. It was a 1 owner when we bought it 4 years ago , I have been adding fuel conditioner every fill up and she gets used every 6 weeks or so . I have it in for routine annual service ,at a Cummins RV shop, and have been informed that the tank has Algae ,needs to be dropped and cleaned $$$$ ,It didn't affect performance at all but the filter is loaded . How do I keep this from happening again? Being a 98 is a long time , maybe it just caught up with me . Thanks

16 Replies

  • NinerBikes wrote:
    Also, once you get this cleared up, always store your fuel tank full of fuel, so that condensation can't form nightly in your fuel tank.


    This is a good theory but in practical application doesn't make a hill of beans. there is not enough air displacement during the night day cycle to contain enough humidity to develop water in the tank.

    This applies more to huge tanks at the refineries where huge quantities of air / humidity can be drawn in to the tank.
  • RAS43's avatar
    RAS43
    Explorer III
    There are additives specific for algae and should be used in vehicles that sit a lot and don't use up the fuel for many months. And it doesn't need sunlight to form in this case. The algae forms when there is water in the tank so if you have a drain on the bottom of the tank that would help. But most tanks don't have a drain so an additive is needed. Some auto parts stores and most commercial truck dealers should have some.
  • Flay Crosswell wrote:
    It didn't affect performance at all but the filter is loaded . Thanks


    Loaded with what? how did it get there?
  • You need some algae biocide fuel additive. Also, once you get this cleared up, always store your fuel tank full of fuel, so that condensation can't form nightly in your fuel tank. It's that condensation that provides water that provides what algae needs to bloom and grow in your fuel.
  • Very seldom will any vehicle get algae in the tanks, have the shop prove you have algae. Algae requires water and sun to grow, 99% of the time algae will be pumped in, and that can't happen with filters in line. Your first symptom will be continued clogged filters. and low fuel pressure shut downs.

    Black fuel is not algae. take a sample and have it analyzed prior to paying big bucks chasing a problem that you don't have. BTDT over the past 4 years.
    Algae develops a slime that will not pass filters. If you do not have filter problems, 999 times out of a 1000 you don't have algae problems.
  • What are you putting in it for additives - there a lot of different types?

    Bill

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