Fuel Tanks

[1sailaway]

I have approx 120 gallons of diesel fuel in my tank, it has been there for several years. What would be the most economical method of treating the fuel? I am mostly concerned with the bottom of the tank.

[Talbot]

With that amount of fuel, might be worth getting a fuel company to pump out and filter. In UK I would use a double dose of a product called Soltron and get a small in line pump to circulate the fuel, and to ensure that it is well mixed, and then pass through a proper fuel filter, eventually sucking from the very bottom of the tank.

Just found Soltron available in USA at Here

However, if you know that there is a lot of rubbish in the bottom of the tank, save yourself a lot of effort, by syphoning off the bottom couple of inches.

[Vasco]

Look in the yellow pages for a fuel polisher, usually they'll come to the dock and pump the fuel thru a bunch of filters a couple of times. They pump the fuel back into the tank and get all the crud off.

[jim lee]

Take a look in the tank first. When I laid up my boat, about 7 years ago, I left the tank full. (Didin't know it would be 7 years, time flys.) Anyway, when putting the boat back in commissin I unbolted the inspection port and looked in the tank. Belive me I was expecting the worst. The stuff looked brand new! Even the tank was still shiny inside there. The only corrosion was a little on the ends of the inpection plate hold down screws. So I ran it. And it ran fine. Still is running fine two tanks later.

Look before you leap, may be you don't have to leap at all.

-jim lee

[delmarrey]

The problems with old fuels is that it loses some of it's properties. If you have an inspection plate, pull it and check for water on the bottom in the low corner. The water can be extracted.

Next, take a sample. It should be a clear redish color (marine fuels) or yellow color (highway fuels). If there is any milkish or fog to it, HAVE IT filtered. There are companies that specialize in this, but ask how much first.

Then add a diesel additive to give it better performance. If it costs more then $200 for all this, pump it out and add new. The old stuff you can sell to someone with a diesel heating system or farm smug pots.

At some of our fuel site we run Bio-diesel. I would NEVER run that through a boat without lots of extra filters. Plus you have to up grade all the hoses an seals.

[Alan Wheeler]

I use to play in the fuel storage game ayears back.
Bio Deisel has a very low sulphur content. The problem with that is the way they get the last bit of sulpher out of the fuel also reduces the aromatics in the fuel. The aromatics are what keep the nitrile rubber seals from shrinking. New seals are OK, but old ones will start leaking. This is going to become a big problem worldwide for countries that are in the process of reducing Sulphur content in fuel for polution reasons. Some countries have signed to this and are reducing bit by bit in steps over the next five years. Most british motors shouldn't be affected. but any thing that has a Japanese built fuel pump, built before 1985, will most likely start leaking and require the seals to be replaced.

Now on to the original post, water is your main enemy. You need to check if water is in there. If it is and is in a large enough quantity, then it is also possible that you have a Desiel bacteria. If you are going to drain all the fuel out and make sure the tank is clean, then no problem. But if you can't or don't want to. Then be very careful about dosing your tank with Chenicals that contain a Biocide. It's great at killing the little blighters, but I will explain why it can also be a problem. Firstly, The Bacteria live at the Water fuel interface. There are several breeds and each is looks a little different. But mostly it looks like a redish brown scungy slimy bluck. It usually is happy to live at the interface. But if it dies for several reasons, maybe the ater has evaporated away, or you have doesed the tank with a chemical, then the stuff dies and floats up into the fuel. As soon as you get into ruff water and the tank is sloshed about, the gunk mixes through the fuel and of course into the fuel filters where it instantly blocks them up. Usually at the most inconveniant time. So as a warning, if you dose a contaminated tank, make sure you can remove the stuff from the fuel before you put to sea. Otherwise it is sometimes safer to leave it there till you can get to somewhere safe to do it. Eventually it has to be done. I have seen really bad tanks where you could scrape the stuff off the tank walls and bottom with spade like you were digging up the lawn.
When we cleaned tanks like some have described, we had a speacal high pressure nozzel, much like a pressure water sprayer, that flailed around the tank and blasted the rubbish of the surfaces of the tank. It would be left going over night or longer. Big massive filters kept recycling the fuel back to the tank.

And lastly, here is a little tip. Bug only grows in the presence of water. Take away the water, you get rid of the bug. Water gets into a tank via many way's, but the most common is condensation. Hot return fuel heats up the tank. The tank is lowering whilest engine is running. Slowly yes, but it still goes down. It has to suck the same volume of air back into the tank. The air is full of moisture and as the tank cools after the engine is finished with, the water condenses out of the air onto the walls of the cooling tank and runs down into the fuel. So first rule is after each outing, fill the fuel tanks to the brim. No or little air, no water.
Of course, that may not always be possible. Ever seen those water crystles you put into pot plants??? Well they absorb water, but believe it or not, they don't absorb fuel. So you get some of those and place them into a bag of heavey weight nylon material that has a fine woven netting look to it. Not sure where yopu guy's would find iit but think creatively. Put a lead sinker in it, a SST fishing line crimped to an end of it and drop it to the bottem of the tank. It absorbs water and not fuel. I did that as a job. I set these up in tanks from Jetskis to underground fuel bunkers for Airports where we were absorbing a huge amount of water at a time.

[delmarrey]

What is Biodiesel?

Biodiesel is a diesel replacement fuel that is manufactured from vegetable oils, recycled
cooking greases or oils, or animal fats. Because plants produce oils from sunlight and air,
and can do so year after year on cropland, these oils are renewable. Animal fats are
produced when the animal consumes plant oils and other fats, and they too are renewable.
Used cooking oils are mostly made from vegetable oils, but may also contain animal fats.
Used cooking oils are both recycled and renewable.
The biodiesel manufacturing process converts oils and fats into chemicals called long
chain mono alkyl esters, or biodiesel. These chemicals are also referred to as fatty acid
methyl esters or FAME. In the manufacturing process, 100 pounds of oils or fats are
reacted with 10 pounds of a short chain alcohol (usually methanol) in the presence of a
catalyst (usually sodium or potassium hydroxide) to form 100 pounds of biodiesel and 10
pounds of glycerine. Glycerine is a sugar, and is a co-product of the biodiesel process.
Raw or refined vegetable oil, or recycled greases that have not been processed into
biodiesel, are not biodiesel and should be avoided. Research shows that vegetable oil
or greases used in CI engines at levels as low as 10% to 20%, can cause long-term engine
deposits, ring sticking, lube oil gelling, and other maintenance problems and can reduce
engine life. These problems are caused mostly by the greater viscosity, or thickness, of
the raw oils (around 40 mm2/s) compared to that of the diesel fuel for which the engines
and injectors were designed (between 1.3 and 4.1 mm2/s). To avoid viscosity-related
problems, vegetable oils and other feedstocks are converted into biodiesel. Through the
process of converting vegetable oil or greases to biodiesel, we reduce viscosity of the fuel
to values similar to conventional diesel fuel ( biodiesel values are typically between 4 and
5 mm2/s).

ASTM International is a consensus based standards group comprised of engine and fuel
injection equipment companies, fuel producers, and fuel users whose standards are
recognized in the United States by most government entities, including states with the
responsibility of insuring fuel quality. The specification for biodiesel (B100) is ASTM
D6751-03. This specification is intended to insure the quality of biodiesel to be used as a
blend stock at 20% and lower blend levels. Any biodiesel used in the United States for
blending should meet ASTM D6751 standards.
The definition of biodiesel within ASTM D6751 describes long chain fatty acid esters
from vegetable or animal fats that contain only one alcohol molecule on one ester
linkage. Raw or refined vegetable oils contain three ester linkages and are therefore not
legally biodiesel. Biodiesel can be made from methyl, ethyl, isopropyl, and otheralcohols, but most biodiesel research focuses on methyl esters and virtually all
commercial-production in the United States today uses methyl esters. Some research has
occurred on ethyl esters (biodiesel produced with ethanol as the alcohol rather than
methanol), however higher ethanol prices relative to methanol, lower ethyl ester
conversions, and the difficulty of recycling excess ethanol internally in the process, have
hampered ethyl ester production in the commercial marketplace. Therefore, in this
document we will only consider methyl esters.
Biodiesel is a legally registered fuel and fuel additive with the U.S. Environmental
Protection Agency (EPA). The EPA registration includes all biodiesel meeting the ASTM
International biodiesel specification, ASTM D 6751, and is not dependent upon the oil or
fat used to produce the biodiesel or the specific process employed.
Do not be fooled by other so-called “biofuel” products, many of which are being offered
to consumers without the benefit of EPA registration or extensive testing and
demonstrations. In fact, if you purchase methyl ester that does not meet ASTM biodiesel
standards, it is not legally biodiesel and should not be used in diesel engines or other
equipment designed to operate on diesel fuel. Methyl esters are used as an industrial
lubricant and solvent in some applications so be sure to purchase only ASTM grade
methyl esters (i.e. biodiesel).
Biodiesel is a recognized alternative fuel under the Energy Policy Act of 1992 (EPAct) as
amended in 1996. EPAct requires that over 75% of new vehicle purchases by certain
federal, state, and alternative fuel provider fleets be alternative fueled vehicles. As a
recognized alternative fuel, any vehicle certified to run on B100 could qualify under the
alternative fuel vehicle purchase provisions of EPAct, but it does not appear that any
vehicles meeting this requirement are available today. B100 is more expensive than other
alternative fuel options, and the original equipment manufacturer (OEM) community has
had little interest in certifying vehicles on B100, so this vehicle credit has not created a
market for biodiesel.
EPAct was amended in 1998 by the Energy Conservation and Reauthorization Act
(ECRA). The amendment allowed qualified fleets to use B20 in existing vehicles to
generate alternative fuel vehicle purchase credits, with some limitations. This has created
significant B20 use by government and alternative fuel provider fleets. For more
information on using biodiesel to fulfill EPAct requirements, see Chapter 8, Using
Biodiesel Under the Energy Policy Act.
As biodiesel grows in popularity, some states are beginning to develop biodiesel
incentive policies to promote biodiesel use and production. State policies can change
rapidly, so please contact your state agencies or the National Biodiesel Board for more
information.

Biodiesel Displaces Imported Petroleum
The fossil fuel energy required to produce biodiesel from soybean oil is only a fraction
(31%) of the energy contained in one gallon of the fuel.2 You get 3.2 units of fuel energy
from biodiesel for every unit of fossil energy used to produce the fuel. That estimate
includes the energy used in diesel farm equipment and transportation equipment (trucks,
locomotives), fossil fuels used to produce fertilizers and pesticides, fossil fuels used to
produce steam and electricity, and methanol used in the manufacturing process. Because
biodiesel is an energy-efficient fuel, it can extend petroleum supplies and makes for
sound state or federal energy policy.
Biodiesel Reduces Emissions
When biodiesel displaces petroleum, it reduces global warming gas emissions such as
carbon dioxide (CO2). When plants like soybeans grow they take CO2 from the air to
make the stems, roots, leaves, and seeds (soybeans). After the oil is extracted from the
soybeans, it is converted into biodiesel and when burned produces CO2 and other
emissions, which return to the atmosphere. This cycle does not add to the net CO2
concentration in the air because the next soybean crop will reuse the CO2 in order to
grow.
When fossil fuels are burned, however, 100% of the CO2 released adds to the CO2
concentration levels in the air. Because fossil fuels are used to produce biodiesel, the
recycling of CO2 with biodiesel is not 100%, but substituting biodiesel for petroleum
diesel reduces life-cycle CO2 emissions by 78%. B20 reduces CO2 by 15.66%.3
Biodiesel reduces tailpipe particulate matter (PM), hydrocarbon (HC), and carbon
monoxide (CO) emissions from most modern four-stroke CI engines. These benefits
occur because the fuel (B100) contains 11% oxygen by weight. The presence of fuel
oxygen allows the fuel to burn more completely, so fewer unburned fuel emissions result.
This same phenomenon reduces air toxics, because the air toxics are associated with the
unburned or partially burned HC and PM emissions. Testing has shown that PM, HC, and
CO reductions are independent of the feedstock used to make biodiesel. The EPA
reviewed 80 biodiesel emission tests on CI engines and has concluded that the benefits
are real and predictable over a wide range of biodiesel blends (Figure 1, page 5).4

3.7 B100 Microbial Contamination
Biocides are recommended for conventional and biodiesel fuels wherever biological
growth in the fuel has been a problem. If biological contamination is a problem, water
contamination needs to be controlled since the aerobic fungus, bacteria, and yeast
hydrocarbon utilizing microorganisms (HUMBUGS) usually grow at the fuel-water
interface. Anaerobic colonies, usually sulfur reducing, can be active in sediments on tank
surfaces and cause corrosion. Since the biocides work where the HUMBUGS live (in the
water), products that are used with diesel fuels will work equally well with biodiesel.

You can get the full document at this link.........................._/)

http://www.nrel.gov/vehiclesandfuels...fs/tp36182.pdf

[Talbot]

I really wanted to know that