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Fuel additives

Discussion in 'Technical Discussion' started by Jnicholas, Mar 26, 2014.

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  1. Jnicholas

    Jnicholas Member

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    Getting ready for our first fill up with our new 450 Voyager. These are my first marine diesels so not sure what, if any additives I should be using. Are you adding both a biocide and stabilizer? Or one or the other? Appreciate any feed back.
  2. Capt J

    Capt J Senior Member

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    A biocide is a stabilizer for diesel. Diesel Kleen makes a good one in, I think their bio kleen comes in a red bottle.
  3. RT46

    RT46 Senior Member

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    I use diesel kleen.

    be careful of loading up on any additive during your first few trips.
    you could end up cleaning your tank and clogging your filters.

    It would be best to have the tanks professionally cleaned and polished before dumping lots of additive into a tank of a boat that you have just bought.

    make sure you have lots of extra filters.

    good luck with the new boat.
  4. Savasa

    Savasa Senior Member

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    Morning,
    If your tanks and fuel are clean additives are unnecessary. Biocide if in tropical areas. Just my $.02.
    Peter
  5. Capt Ralph

    Capt Ralph Senior Member

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    Are you already having problems? I would hold off on adding anything.

    Getting fuel from a reliable source should be the first thought. If there are any problems, then ad or service as required.

    Tank cleaning would also just be needed if you find problems.

    Keep an eye on your filters and use your ship. Lack of use is your enemy.
    Get out there and run your new ship. You may find your in good shape.

    There are marine pumps labeled ValveTech. These fuels have some additives already mixed in. ValvTect - Valvtect Marine Diesel
    If your just wanting to baby your new ship, I'd use these fuels.

    keep us up on your adventures.
  6. Jnicholas

    Jnicholas Member

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    Thanks for replies. Rancor filters were pretty dirty. Fuel in tank and collected fuel during the bleeding process looks good and clean. We have been out in the swells several times and haven given the tanks a good shake. I will keep an eye on filters and try to head off a unplanned stop!

    I do buy fuel at at valvetech dealer. Lots of boats around us. I'm sure fresh fuel from dealer.

    Thanks again
  7. Capt Ralph

    Capt Ralph Senior Member

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    I'm not Carver heavy. Guessing 5.9B Cummings. Usually easy to get to secondary filters.
    Watch the Racor bowls and keep Primary AND secondary spare filters with you. Also a catch bucket, funnels, 'sorb towels and a old resealable oil pail.
    If you have the dual Racor setup, try keeping 10 Mic filters in them. If a single Racor, 10 or 30 mic and watch your low pressure gages.
  8. ksbguy

    ksbguy Member

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    Stay away from biocides unless you have a microbial problem. Biocides are very corrosive to the injection system.

    Multi stage filtration is your best bet. 30, 10 and 2 micron on engine.

    A vacuum gauge on the racor is a good indication that you have filters clogging or a restriction somewhere in the system.

    There's a myth that diesel has Algae. There's no Algae in diesel as it cannot grow without sunlight in a fuel tank.

    The black stuff you will see in there is asphaltene which is the diesel breaking down. Diesel is now refined with chemicals so it doesn't take long for it to start breaking down and create the black stuff in your tanks.

    Your biggest concern should be water. Make sure there is no water in your fuel tanks. Check your fuel fill fitting o-rings and replace them annually. Also get your fuel from a reliable source that cycles fuel often so you know the fuel is fresh.

    Water in the fuel will cause microbial growth.

    I myself won't use valvetect fuel because they put biocides in it...

    There's a lot of good information on boatdiesel.com.
  9. Marmot

    Marmot Senior Member

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    The most commonly used biocide, Biobor, is a corrosion inhibitor. It is misleading to say the least to make a statement warning people to "stay away from biocides" and link your reasoning with a general falsehood.

    Waiting until you have contaminated fuel is not a very good approach. The most commonly used biocides used in marine and aviation distillate fuels acts as a prophylactic and prevents microbial contamination before it can do any harm.

    It is generally the by-products of biological life and death that produce corrosive chemicals. Preventing biological growth is the best step you can take to prevent or reduce corrosive contamination.



    Check the label and see if the biocide meets Mil-S-53021. If it does, you can use it in any diesel and your stable of gas turbines as well.


    Asphaltenes are found in all crude oils. The hydrotreating process used to remove sulfur to produce ULSF fuel also removes many of the aromatics that used to delay the creation of asphaltenes in diesel fuel. Diesel fuel is still refined the way it was a century ago, by fractional distillation. There are several post distillation process that modify the characteristics of the middle distillates and produce more gasoline from a barrel of oil but oil refining is still based on the same physics that it always was. Some additives introduce aromatics and increase the stability of the fuel which delays the production of the long chain molecules called asphaltenes.

    That is your choice, but using your misinformed opinions to try and influence others to avoid using beneficial products is not doing anyone a service.

    There's a lot of good information on boatdiesel.com.[/QUOTE]

    And some really bad "information" as well by the look of it ...
  10. ksbguy

    ksbguy Member

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    And some really bad "information" as well by the look of it ...[/QUOTE]

    You believe it's a corrosion inhibitor because the bottle says it is but do you understand why the bottle says that? It says that because micro organisms are corrosive and the biocide kills micro organisms which prevent the corrosion. Check the ph of biocide next time, you're adding acid to your fuel tanks...

    What do you think happens to the micro organisms in your fuel when you add biocide? They are killed and pile up in the bottom of your tanks to later clog your filters when you need your engines the most in rough water. This is preventive maintenance?

    I believe you are mis informed. Keeping water out of fuel is the best preventive maintenance you can do. If you have no water there are no micro organisms to kill so why would constantly add acid to your fuel tanks?

    Now I do agree that if you constantly have water in your tanks and the biological growth is out of control that you are forced to use a biocide but that is a last resort.

    The only reason I don't use valvetect is because of the biocide and my argument above. The lubricity enhancers are a good idea but no need for constant biocide.

    Also if you have a water problem and are constantly adding biocide your masking your problem. Problems should be solved at the root and not further downstream as your advising.

    As for the boat diesel site every site has bad information but if you spend some time on there it's easy to figure out how to properly filter your information. I've had nothing but professional help there when needed from top notch guys.
  11. Marmot

    Marmot Senior Member

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    So, save me and the rest of the membership the effort and tell us what the pH is.

    You might wish to read and understand MIL-S-53021A before replying with more misinformation regarding the value of using one of the biocide additives that meet that standard.

    No, preventive maintenance is using a biocide in low dosages to inhibit the growth of bacteria. The condition you describe is what happens when no biocide is used and a heavy growth or "infection" occurs. This is basic fundamental fuel management knowledge.

    About what?

    Wow, what an amazing revelation! Thanks for sharing that.

    All distillate fuels contain water. There is no such thing as an anhydrous distillate fuel. It is good practice to use a biocide at low levels (industry standard for aviation and marine is around 135ppm) to inhibit bacterial growth.

    You keep talking about adding acid as if you have some knowledge of the subject. Please let us know what the pH standard is for distillate fuels. How is it measured? What are the limits and what is the pH of the fuel you normally upload? What is the pH of the most commonly used biocide?

    Please describe the standard test method for acids in oils and petroleum fuels.


    With proper fuel management techniques and prophylactic use of biocides it should not get "out of control." The use of biocides is not a "last resort" it is a standard technique to inhibit bacterial growth in fuel tanks. It is commonly used by airlines to protect the fuel systems of aircraft and engines from the harmful effects of bacterial infection which include filter clogging and corrosion of transfer pumps, tanks and fuel lines and most importantly, the precision fuel metering components used in modern gas turbines.
  12. ksbguy

    ksbguy Member

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    I'm not going to continue to discuss this here, it's gotten past the point of being productive for anyone reading it...

    Unfortunately you are making this way more complicated than it is or needs to be.

    You can get this information from any major petroleum supplier. Here is BPs opinion. In page 3, first paragraph they outline the disadvantages of using biocide and cleary state that a maintenance dose is no more effective than regular water draining.

    http://www.bp.com/liveassets/bp_int...ts/downloads_pdfs/f/Long_Term_Storage_ADF.pdf

    I don't have any biocide here to test for you because I have never purchased it in my life but if my memory serves me right it was acidic from a bottle I tested a gentlemen at the marina had a while back. Neutral PH is defined as 7.0 so anything lower is going to be acidic. A good practice is if you get water in your racor to test the ph of the water and if its bellow 5.5-6.0 you have a serious problem with corrosion in your tanks. You can use a ph test kit from any pool supply place.

    In almost 20 years and many thousands of gallons of fuel I have never added any biocide to any diesel fuel I've put in any boat or machine I have owned. I simply make sure I have access to my tanks, I check them for water and check my filters for water. If I see any water I drain it, simple. Sure there is some water in all fuels but not enough to cause microbial growth. Regardless if there is water in the fuel you take on or not any measurable amount will work it's way to the bottom of your tanks in due time so why not just drain the water? On my current boat I have never seen any water in the tanks and I store my tanks empty every year.

    This is one persons opinion based on what has worked for him and how he has seen biocides cause problems for others around him. I'm not condoning the use of it I just don't believe it is necessary if you keep the water out of your fuel. You're going to continue to argue that you need it so use it :)
  13. Marmot

    Marmot Senior Member

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    I don't feel like wasting anymore time with you either as it is very obvious you are just making this up as you go along for some reason or other.

    Your suggestion to test the water indicates you don't know the difference between the acid number of fuel and the pH of water. You came on here claiming that biocides are acid and using them acidifies diesel fuel.

    When you could or would not tell us how to test diesel fuel pH or even say what diesel fuel pH range might be or what standards apply, you come back with a conversation about water.

    It is a given that free water in diesel fuel is not a good thing, and free water in diesel fuel is normally acidic. I can't imagine anyone who comes here to provide advice about fuel management NOT knowing that so don't waste our time falling back on water bottom pH readings instead of telling us how you know that biocides acidify diesel fuel and cause corrosion.

    You made the statements, it is up to you to back them up with science or citations. Don't try and divert the thread, just answer the questions. It is up to you to show your advice is based on science and standard industry procedures. If you can't (which I know you can't because everything you have written is nonsense except for telling us that water is not good) then I suggest you find another website to spread your bad advice.
  14. ksbguy

    ksbguy Member

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    Did you read the article? I backed up my argument with a document from a petroleum manufacture. Obviously you must know more than the manufacture does. You seem to ignore everything that does not give you something to argue about.

    I wasn't aware this was a diesel PH discussion, you decided to turn it into such since you will not agree that in the absense of water biocides aren't needed. Go back and read what I wrote.

    Nowhere here did I mention testing the PH of diesel fuel. I suggested testing the water if you see any. I think it's quite obvious diesel ph isn't tested the same way as water. To my knowledge water completely separates from fuel so yes it can be tested quite easily with a pool test kit.

    Regardless of whether biocide acidifies diesel fuel or not the point still remains that in the absense of water it is not needed.

    Above you said:
    "It is a given that free water in diesel fuel is not a good thing". Is that a scientific statement? What is "not a good thing"?

    Maybe next time you argue the use of biocides you should also explain to people what causes the microbial growth so that people can make an informed decision for themselves on whether to use biocides or not instead of being told to use them. That is all I was trying to do but rest assured it's the last time.

    And no, I don't agree that everyone that comes on here understands the water problem. This started in a Carver section where some owners are buying a boat for the first time...

    Like I said previously you will continue to argue and tell people to add biocides to fuel so be it.
  15. rgsuspsa

    rgsuspsa Member

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    Most diesel fuel biocide additives contain chlorine, which is in fact corrosive to metals, particularly aluminum fuel tanks, steel alloys and copper alloys as used in fuel injection system components. For this reason alone the routine
    use of biocide in an actively utilized vessel which does not have water leaking fuel caps has not been necessary in my experience.

    Experiences of others may differ, and there are few absolutes in a subject which has numerous variables, most of which are out of the control of the vessel operator. Decide accordingly.
  16. Marmot

    Marmot Senior Member

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    I guess you guys need to let MTU, the military, and the airlines know that they are wrecking their engines by approving or recommending the use of biocides.

    No one is saying you MUST use the stuff, but I am saying it is ignorant disinformation to tell people that using it is dangerous to the fuel tank or engine. What I have read here as the reason on person will not use a biocide is as much snake oil mis and dis information as the hucksters who flog kerosine and call it magic fuel sauce.

    Ignorance about the benefits and proper application of an additive is as bad as intentional disinformation for and against the use of those products. Informed decisions don't come from the type of disinformation posted in this thread about the reasons one individual will not use a biocide.

    The data is readily available, there is a lot of it, look it up and read it for yourself.
  17. rgsuspsa

    rgsuspsa Member

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    Marmot: Sarcasm is a poor substitute for informed reasoning.
    Resorting to it speaks volumes about its writer, and nothing about those to whom it is directed.
  18. gr8trn

    gr8trn Senior Member

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    ksb,
    I read the 2005 guide for storing diesel by BP. It seemed to be pretty straight forward.
    Avoid water, heat, metals like zinc copper and other alloys.

    Under the category of Additives to improve storage life:

    "Fungicides/Biocides. These work by stopping fungus and bacteria from growing in the fuel and so prolong the life of the fuel. They are only effective on fungus and bacteria and will not stop other oxidation reactions from taking place. They are normally active at the water fuel interface where the fungus and bacteria grow. If fungus is present then a kill dose is required. Otherwise a maintenance dose is used to stop fungus growing."

    "maintenance doses are effective but no more so than regular water draining"

    There is no mention of biocides causing acidic corrosion of the engine parts, even though that seems to be an area of concern.

    I have used Stabil brand fuel additive with good results so far and am leaning toward continuing. Interestingly, the fuel dock master says his fuel doesn't need any help. He may be right, I may be crazy, but it just may be a lunatic that has stored diesel for a long time with no issues so far, knock wood.

    I certainly have no interest in Stabil:Diesel Formula STA-BILĀ® Brand - How To Video - YouTube

    -Greg
  19. NYCAP123

    NYCAP123 Senior Member

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    Your fuel dock probably sells Valv-Tech fuel which already has the biocide in its formulation. What lawsuits that company would be facing if it did in fact cause acidic corrosion, but I haven't heard of any.
  20. gr8trn

    gr8trn Senior Member

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    NYCAP,
    You may be right, I have not asked him. Next time I shall. Although I have not seen any signage to indicate he uses ValvTech.
    -Greg