fuel additives

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Bill

fuel additives

Post by Bill »

This is my first experience with diesel fuel. Assuming that the tanks are clean (CD28), and the fuel and lines are clean, what additives can you (or suppose to) add to the fuel? A brief literature search and a trip to several marine stores confused me. Anti-condensation fluid, mystery oil, biocide, fungus inhibitor, etc.; all seem logical, but there MUST be a point of diminishing return for all the
"helpers" put into the fuel tank. If there are needed additives, what should they be? Thanks for whatever input based on experience you can give me...Bill



meislandbill@yahoo.com
Larry DeMers

Re: fuel additives

Post by Larry DeMers »

Well, there are truly a blizzard of concoctions out there to help you keep your engine running well. Most work fine by themselves, but I wonder about combining them with each other. To me, the less I add to the fuel the better, so here is what I do, and it has worked in my area.
With a clean tank and no fuel 'problems', I add 1 oz of biocide and a bit of water displacement therapy (isopropal alcohol which surrounds the dropplet of water, and allows it to be burned up) to the tank each time I top it off. Notice I said top it off, not fill it up. Topping it off helps limit the condensation that forms in the tank against the bare walls, and drips water into the fuel, where it sinks to the bottom where the microbes live..at the interface of the oil and water layers. These microbes live and die there, and over time form a black gooey substance that sticks like crazy glue to every surface in the tank, the hose, the fuel filter chamber etc. eventually plugging the filter media and stopping the engine. Evidence of this condition are tiny black specks floating in the fuel, which accumulate in the sediment trap of your filters (get a Racor filter with the clear plastic bowl and quick drain fitting on it. You can then see what is in your system and act accordingly).

You might think about installing a fuel 'self-polishing' system onboard. This consists of a truck type electric replacement fuel pump (I have one from Napa that puts out around 40 gph) and some 2 way fuel valves to direct the flow thru the filter, then back to the tank, where it stirs up the sediment and that then gets sent thru the filter. Generally an hour or two every month will keep the system free of water and microbial growth. We do ours while the boat is at the dock, and we are loading it up..it's still hooked to the shore power, so the charger is powering the pump. It certainly could be run while at anchor also.

That is what I would do to start, then watch to see what further problems your tank has which may need attention. It may have none, but there is an equal chance that further work will be needed to get it into shape..depending on how long it was laid up, what condition it was in when laid up etc.

Cheers,

Larry DeMers
s/v DeLaMer
Cape Dory 30
Apostle Islands of Lake Superior

Bill wrote: This is my first experience with diesel fuel. Assuming that the tanks are clean (CD28), and the fuel and lines are clean, what additives can you (or suppose to) add to the fuel? A brief literature search and a trip to several marine stores confused me. Anti-condensation fluid, mystery oil, biocide, fungus inhibitor, etc.; all seem logical, but there MUST be a point of diminishing return for all the
"helpers" put into the fuel tank. If there are needed additives, what should they be? Thanks for whatever input based on experience you can give me...Bill


demers@sgi.com
D. Stump, Hanalei

Re: How long does it take...????

Post by D. Stump, Hanalei »

Captain DeMers,

How long do you think it would take for diesel to grow biologicals or go bad? I emptied the tank the end of last year and filled it with new diesel. I did NOT add anything to the tank. Is the fuel still good?

Dave Stump
Hanalei
Larry DeMers

Re: How long does it take...????

Post by Larry DeMers »

Howdy Capt. Dave,

I would bet that it is fine. The reasoning goes like this: Condensation is caused by the difference between the outside temps and the fuel temp. Running the engine recirculates warmed fuel back into that tank, where it warms the air over the fuel. The very cold surfaces of the tank allow condensation to bead up on it's surface, dripping down into the fuel as the beads grow. The causative factor here is the warmed fuel and the air space over the fuel.
Since you filled up last fall, and the temps have been mild but cold compared to summer temps for instance, I would not expect that you have much in the way of trouble in that tank.
Now when you get aboard, you will be adding the biocide and isopropal alcohol, right? heh..cause soon as you run that engine and recirc your warmed fuel, the process will start up.

Cheers,

Larry DeMers
s/v DeLaMer
Cape Dory 30
Apostle Islands of Lake Superior

D. Stump, Hanalei wrote: Captain DeMers,

How long do you think it would take for diesel to grow biologicals or go bad? I emptied the tank the end of last year and filled it with new diesel. I did NOT add anything to the tank. Is the fuel still good?

Dave Stump
Hanalei


demers@sgi.com
Paul Hierstein

Re: How long does it take...????

Post by Paul Hierstein »

Larry DeMers wrote: Howdy Capt. Dave,

I would bet that it is fine. The reasoning goes like this: Condensation is caused by the difference between the outside temps and the fuel temp. Running the engine recirculates warmed fuel back into that tank, where it warms the air over the fuel. The very cold surfaces of the tank allow condensation to bead up on it's surface, dripping down into the fuel as the beads grow. The causative factor here is the warmed fuel and the air space over the fuel.
Since you filled up last fall, and the temps have been mild but cold compared to summer temps for instance, I would not expect that you have much in the way of trouble in that tank.
Now when you get aboard, you will be adding the biocide and isopropal alcohol, right? heh..cause soon as you run that engine and recirc your warmed fuel, the process will start up.

Cheers,

Larry DeMers
s/v DeLaMer
Cape Dory 30
Apostle Islands of Lake Superior

D. Stump, Hanalei wrote: Captain DeMers,

How long do you think it would take for diesel to grow biologicals or go bad? I emptied the tank the end of last year and filled it with new diesel. I did NOT add anything to the tank. Is the fuel still good?

Dave Stump
Hanalei




So, how much rubbing alcohol do you put in your CD30 tank???

Paul Hierstein
CD30C
Abre Alas
Galveston, Texas



paulhstn@aol.com
Larry DeMers

Re: How long does it take...????

Post by Larry DeMers »

I use a half pint container of Isopropal Alcohol -rubbing alcohol really, as you say, -to a full tank of fuel. The small containers are relatively cheap..like $.75 each last time I bought it (bought a case). Make certain that the caps have an internal seal if you do purchase these small containers from the store. Alcohol is hydroscopic, and will abosrb water vapor if allowed access to the air, which kind of ruins it for our uses.

Larry DeMers

Paul Hierstein wrote:
Larry DeMers wrote: Howdy Capt. Dave,

I would bet that it is fine. The reasoning goes like this: Condensation is caused by the difference between the outside temps and the fuel temp. Running the engine recirculates warmed fuel back into that tank, where it warms the air over the fuel. The very cold surfaces of the tank allow condensation to bead up on it's surface, dripping down into the fuel as the beads grow. The causative factor here is the warmed fuel and the air space over the fuel.
Since you filled up last fall, and the temps have been mild but cold compared to summer temps for instance, I would not expect that you have much in the way of trouble in that tank.
Now when you get aboard, you will be adding the biocide and isopropal alcohol, right? heh..cause soon as you run that engine and recirc your warmed fuel, the process will start up.

Cheers,

Larry DeMers
s/v DeLaMer
Cape Dory 30
Apostle Islands of Lake Superior

D. Stump, Hanalei wrote: Captain DeMers,

How long do you think it would take for diesel to grow biologicals or go bad? I emptied the tank the end of last year and filled it with new diesel. I did NOT add anything to the tank. Is the fuel still good?

Dave Stump
Hanalei



So, how much rubbing alcohol do you put in your CD30 tank???

Paul Hierstein
CD30C
Abre Alas
Galveston, Texas


demers@sgi.com
Tom

Correct me if I'm wrong

Post by Tom »

I always thought that rubbing alcohol (isopropyl) contains 30% water. I have a bottle in my hand put out by Thrifty Drug Stores which says alcohol 70%, inactive ingredient: water. Presumably the inactive water is the other 30%. You're working against yourself if you're putting water in your fuel tank. I thought you were supposed to go to the paint store and buy water free alcohol or shellac thinner which is 100% alcohol as water screws up shellac and varnish. A little water in your alcohol doesn't matter if you're getting a back rub, but it might in your fuel tank. Please correct me if I'm wrong.

Tom
Channel Islands, Calif.

Larry DeMers wrote: I use a half pint container of Isopropal Alcohol -rubbing alcohol really, as you say, -to a full tank of fuel. The small containers are relatively cheap..like $.75 each last time I bought it (bought a case). Make certain that the caps have an internal seal if you do purchase these small containers from the store. Alcohol is hydroscopic, and will abosrb water vapor if allowed access to the air, which kind of ruins it for our uses.

Larry DeMers

Paul Hierstein wrote:
Larry DeMers wrote: Howdy Capt. Dave,

I would bet that it is fine. The reasoning goes like this: Condensation is caused by the difference between the outside temps and the fuel temp. Running the engine recirculates warmed fuel back into that tank, where it warms the air over the fuel. The very cold surfaces of the tank allow condensation to bead up on it's surface, dripping down into the fuel as the beads grow. The causative factor here is the warmed fuel and the air space over the fuel.
Since you filled up last fall, and the temps have been mild but cold compared to summer temps for instance, I would not expect that you have much in the way of trouble in that tank.
Now when you get aboard, you will be adding the biocide and isopropal alcohol, right? heh..cause soon as you run that engine and recirc your warmed fuel, the process will start up.

Cheers,

Larry DeMers
s/v DeLaMer
Cape Dory 30
Apostle Islands of Lake Superior

Paul Hierstein wrote:
So, how much rubbing alcohol do you put in your CD30 tank???

Paul Hierstein
CD30C
Abre Alas
Galveston, Texas


TomCambria@mindspring.com
Larry DeMers

Re: Correct me if I'm wrong

Post by Larry DeMers »

That is probably correct for rubbing alcohol.. never used the stuff. I buy my isopropal in the small half pint plastic bottles, intended for car gas tanks..'Heat' is a similar product, but not isopropal I understand, but on the same shelf there are other brands that *are* isopropal, and say so. How much water it has in it is inmaterial..it is how much it can hold that is important, right? Or at least it would seem so..

Cheers,

Larry Demers

Tom wrote: I always thought that rubbing alcohol (isopropyl) contains 30% water. I have a bottle in my hand put out by Thrifty Drug Stores which says alcohol 70%, inactive ingredient: water. Presumably the inactive water is the other 30%. You're working against yourself if you're putting water in your fuel tank. I thought you were supposed to go to the paint store and buy water free alcohol or shellac thinner which is 100% alcohol as water screws up shellac and varnish. A little water in your alcohol doesn't matter if you're getting a back rub, but it might in your fuel tank. Please correct me if I'm wrong.

Tom
Channel Islands, Calif.

Larry DeMers wrote: I use a half pint container of Isopropal Alcohol -rubbing alcohol really, as you say, -to a full tank of fuel. The small containers are relatively cheap..like $.75 each last time I bought it (bought a case). Make certain that the caps have an internal seal if you do purchase these small containers from the store. Alcohol is hydroscopic, and will abosrb water vapor if allowed access to the air, which kind of ruins it for our uses.

Larry DeMers

Paul Hierstein wrote:
Larry DeMers wrote:
Paul Hierstein wrote:
So, how much rubbing alcohol do you put in your CD30 tank???

Paul Hierstein
CD30C
Abre Alas
Galveston, Texas


demers@sgi.com
D. Stump, Hanalei

Re: Tom, You are correct...and....

Post by D. Stump, Hanalei »

Tom and Larry,

You can purchase 90% isopropyl at the drug store, it is usually right next to the rubbing alchol. The point is that the alchol will azeotrope(sp) with the water,i.e. it will combine with the water and take it over into the fuel stream so that it can be burned. Hey, here's a question, can you just use the same stuff for drying the gasoline in your cars gas tank for the diesel in you ships tank?

Oh, by the way, for disinfecting purposes, 70% is better than 90%!

Dave Stump
Hanalei
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