While topping off the diesel tank prior to winter storage, I noticed a label on the pump stating the diesel was treated with a biocide and a stabilizer. The college kids manning the gas dock knew nothing other than what was written on the label. Does anyone know whether diesel fuel is so treated by the supplier? Even if the original supplier (the one who may have placed the label on the pump) treats the diesel, what assurance do I have that the same supplier will always be used?
Diesel Additives By Supplier
- Thread starter Steve Carpman11081
- Start date
- Status
No assurances
And for that reason I will add biocide and stabilize when I winterize this season. Our pumps at the marina say the same thing, but who DO you believe?
And for that reason I will add biocide and stabilize when I winterize this season. Our pumps at the marina say the same thing, but who DO you believe?
Why on earth would you top of a tank???
Old diesel fuel is not good!!!! Here on the gulf we sail all year so winter storage isn't a problem. But I try to keep just enough fuel in my tank so that it is fresh, usually about 10 gallons. I have never seen water in my fuel!!! I know the old song and dance about condensation but that isn't a real problem with a 20-40 gallon tank. But fuel sitting around in a tank for years isn't good. Tom www.yachtsurvey.com/myth_of_condensation_in_fuel_tanks.htm
Old diesel fuel is not good!!!! Here on the gulf we sail all year so winter storage isn't a problem. But I try to keep just enough fuel in my tank so that it is fresh, usually about 10 gallons. I have never seen water in my fuel!!! I know the old song and dance about condensation but that isn't a real problem with a 20-40 gallon tank. But fuel sitting around in a tank for years isn't good. Tom www.yachtsurvey.com/myth_of_condensation_in_fuel_tanks.htm
there are other reasons for topping off
I read the article P323 included but I'm not buying the argument. P323 doesn't live in a winter-climate zone and doesn't have a clue about the reality of temperature swings between night and day north of Dixie. Several times last winter in Connecticut we had temperatures of -10 before sunrise and 30 after sunrise: inside a shrink-wrapped boat thermal heating from the sun can swing the cabin air temperature 70 degrees in a few hours. Fuel tanks can be very cold in relation to the cabin air depending on where they're located. No, condensation is not a myth but it is subject to local conditions. There are 2 other reasons given for topping off a diesel tank: holding down fungus growth (the microbes reproduce more quickly in the presence of air) and to prevent air bubbles from entering injector lines, causing the need for injector bleeding in engines that aren't self-bleeding. I won't stop topping off until I'm satisfied on all of these points. On the other hand, I've never seen a marina gas dock I would trust to know the answer to the question about what they're pumping so I use tiny amounts of Star-tron on each fill.
I read the article P323 included but I'm not buying the argument. P323 doesn't live in a winter-climate zone and doesn't have a clue about the reality of temperature swings between night and day north of Dixie. Several times last winter in Connecticut we had temperatures of -10 before sunrise and 30 after sunrise: inside a shrink-wrapped boat thermal heating from the sun can swing the cabin air temperature 70 degrees in a few hours. Fuel tanks can be very cold in relation to the cabin air depending on where they're located. No, condensation is not a myth but it is subject to local conditions. There are 2 other reasons given for topping off a diesel tank: holding down fungus growth (the microbes reproduce more quickly in the presence of air) and to prevent air bubbles from entering injector lines, causing the need for injector bleeding in engines that aren't self-bleeding. I won't stop topping off until I'm satisfied on all of these points. On the other hand, I've never seen a marina gas dock I would trust to know the answer to the question about what they're pumping so I use tiny amounts of Star-tron on each fill.
Your tanks worst enemy
Your worst enemy in the northeast is the marina fuel storage tanks, and the marina operators. The tanks sit dormant all winter, and you have no idea what quality fuel they are supplying. The safest thing is to buy your fuel at a reputable gas station, leave it in the jug a few days before transfering it to your tank, pour it slowly without inverting the jugso that you do not pour out the bottom inches of the jug. Look inside the jug for contaminants with a flashlight, they are much easier to see in Hiway diesel than in the dyed red marine/home fuel. If you must get at a marina put it in a jerry jug so that you can let it settle then inspect with a bright lite before you put it in your tank.
Your worst enemy in the northeast is the marina fuel storage tanks, and the marina operators. The tanks sit dormant all winter, and you have no idea what quality fuel they are supplying. The safest thing is to buy your fuel at a reputable gas station, leave it in the jug a few days before transfering it to your tank, pour it slowly without inverting the jugso that you do not pour out the bottom inches of the jug. Look inside the jug for contaminants with a flashlight, they are much easier to see in Hiway diesel than in the dyed red marine/home fuel. If you must get at a marina put it in a jerry jug so that you can let it settle then inspect with a bright lite before you put it in your tank.
My experience with a marina
I always like to keep my tank pretty full. So when I'm down 7-8 gallons, I'll use my 6 gal jerry jug to top off. I usually use marina fuel since it's convenient to get where I am. I was at a marina in Maine a couple summers ago and the facility had a major turnover in fuel. So one is to assume that it was fresh and clean. I filled my jerry jug and went on a cruise. When I finally filled my tank from the jerry jug about a week later, I was appalled to see sediment in the jug when it came near the end of the jug. So never assume that everyplace has clean fuel. When I took my diesel course about 10 years ago, the very first statement that the instructor said, even before he introduced himself, was, "ALWAYS TREAT ANY FUEL AS SUSPECT". It is a thought that I always have when I buy fuel.
I always like to keep my tank pretty full. So when I'm down 7-8 gallons, I'll use my 6 gal jerry jug to top off. I usually use marina fuel since it's convenient to get where I am. I was at a marina in Maine a couple summers ago and the facility had a major turnover in fuel. So one is to assume that it was fresh and clean. I filled my jerry jug and went on a cruise. When I finally filled my tank from the jerry jug about a week later, I was appalled to see sediment in the jug when it came near the end of the jug. So never assume that everyplace has clean fuel. When I took my diesel course about 10 years ago, the very first statement that the instructor said, even before he introduced himself, was, "ALWAYS TREAT ANY FUEL AS SUSPECT". It is a thought that I always have when I buy fuel.
Condensation and relative humidity
The ability of air to have water depends upon temperature. Air holds almost no water at very low temperatures. So very cold air that warms up is very dry air. My major points about topping off tanks are; 1.fuel gets old 2. the water in your fuel is coming from someplace besides condensation. With my small tank draining makes more sense than topping off. We topped off the fuel in our airplane but it had very large fuel tanks. Plus the gas was used fairly quickly. That said about the only time I ever had water in my sample cup was after a rain.(for non pilots a standard preflite includes drawing a sample of fuel from each tank) I think that the few drops that were in the gas came from the fill cap. Finally for the pilots in our group remember that on a nice hot humid summer day at sealevel it is cold up at 9500'. So when you land after a rapid descent your tank is cold and the increased pressure at sea level causes the warm most air to enter the tanks. I have had water condense on my wings upon landing after being up at 9500' and then landing in Birmingham in summer....My boat has never been much above sea level!!!!
The ability of air to have water depends upon temperature. Air holds almost no water at very low temperatures. So very cold air that warms up is very dry air. My major points about topping off tanks are; 1.fuel gets old 2. the water in your fuel is coming from someplace besides condensation. With my small tank draining makes more sense than topping off. We topped off the fuel in our airplane but it had very large fuel tanks. Plus the gas was used fairly quickly. That said about the only time I ever had water in my sample cup was after a rain.(for non pilots a standard preflite includes drawing a sample of fuel from each tank) I think that the few drops that were in the gas came from the fill cap. Finally for the pilots in our group remember that on a nice hot humid summer day at sealevel it is cold up at 9500'. So when you land after a rapid descent your tank is cold and the increased pressure at sea level causes the warm most air to enter the tanks. I have had water condense on my wings upon landing after being up at 9500' and then landing in Birmingham in summer....My boat has never been much above sea level!!!!
Diesel Stabilizer
If you are concerned about fuel aging then I would suggest using a diesel stabilizer during layup. It'll help keep the fuel fresh but also will keep it from gelling in the real cold weather.
If you are concerned about fuel aging then I would suggest using a diesel stabilizer during layup. It'll help keep the fuel fresh but also will keep it from gelling in the real cold weather.
Issue With Condensation
As a vented tank sits and is heated by the sun during the day and cooled off at night there is going to be some exchange of air in and out. As the warmer moister air is cooled condensation will occur on the tank surface. The more fuel there is in the tank the less space there is for air and less surface area for the moisture to condense upon. I guess you could add a check valve or close off the vent line while is is stored for the winter to keep the air from going in and out but fuel is cheap enough and the tanks are small enough it is simpler just top off the tank.
As a vented tank sits and is heated by the sun during the day and cooled off at night there is going to be some exchange of air in and out. As the warmer moister air is cooled condensation will occur on the tank surface. The more fuel there is in the tank the less space there is for air and less surface area for the moisture to condense upon. I guess you could add a check valve or close off the vent line while is is stored for the winter to keep the air from going in and out but fuel is cheap enough and the tanks are small enough it is simpler just top off the tank.
How much fuel do you use???
I am thinking that we haven't used 20 gallons this year!!! I haven't added any fuel since May. I added fuel then because we were sailing about 160 miles from Mobile to Panama city. Last time I checked we still had over 1/2 tank. If I topped off the tank once a year that would be enough most years. I used a lot this year because twice we had to motor 20+ miles due to lack of wind and once we had to motor about 50 miles due to the wind on our nose going up the ICW. The point I'vm making is that if you are mostly a sailor who tops off regularly you could easily get fuel several years old. Then you start adding stuff to stabilize and to kill growth pretty soon the quality of the fuel is very suspect. Some of these stabilizers are just Isopropanol. If this is mixed with water it can separate from the fuel and cause rust and corrosion in your metal tank. For me the answer is clean fresh fuel not stuff that has been sloshing around for years. Diesel is not like fine wine getting better with age. And a lot of these additives are just snake oil that might do more harm than good.
I am thinking that we haven't used 20 gallons this year!!! I haven't added any fuel since May. I added fuel then because we were sailing about 160 miles from Mobile to Panama city. Last time I checked we still had over 1/2 tank. If I topped off the tank once a year that would be enough most years. I used a lot this year because twice we had to motor 20+ miles due to lack of wind and once we had to motor about 50 miles due to the wind on our nose going up the ICW. The point I'vm making is that if you are mostly a sailor who tops off regularly you could easily get fuel several years old. Then you start adding stuff to stabilize and to kill growth pretty soon the quality of the fuel is very suspect. Some of these stabilizers are just Isopropanol. If this is mixed with water it can separate from the fuel and cause rust and corrosion in your metal tank. For me the answer is clean fresh fuel not stuff that has been sloshing around for years. Diesel is not like fine wine getting better with age. And a lot of these additives are just snake oil that might do more harm than good.
- Status