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Old 16-09-2014, 17:49   #61
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Re: Fuel Polishing System Installation

What should be obvious by now is that several posters have undisclosed conections to additive vendors and are performing an elaborate song and dance. The OP had some good information. I suggest that anyone seaking clarity run from this thread, as it is not what they are selling.
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Old 16-09-2014, 19:03   #62
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Re: Fuel Polishing System Installation

Quote:
Originally Posted by Aloha_float View Post
Put the tank outside for that test. Inside the barn isn't a real fair test.

Corrosion in vapor space is from acetic acid.

All else is misleading...full tanks help prevent vapor space corrosion

There are additives designed specifically to handle vapor space corrosion

Read the battelle report


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Another expert has spoken..... Please oh please explain for us mere mortals how an empty tank on the second floor of an uninsulated barn with the tank vent physically piped outdoors, just like on a boat, is any different than the empty tank on my boat less than 4' away experiencing the same temps, weather and temp swings..? Oh and please do so scientifically.....

Sorry I am all set on the snake oil...
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Old 17-09-2014, 03:57   #63
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Quote:
Originally Posted by Aloha_float View Post

Put the tank outside for that test. Inside the barn isn't a real fair test.

Corrosion in vapor space is from acetic acid.

All else is misleading...full tanks help prevent vapor space corrosion

There are additives designed specifically to handle vapor space corrosion

Read the battelle report

Sent from my iPad using Cruisers Sailing Forum
Have you ever heard of even one case of vapor space corrosion in a boat tank? Right, neither have I.

The problem sailors encounter is not vapor space corrosion, which is corrosion of the top of the tank, but corrosion at the bottom of the tank from water and microbes. This problem is exacerbated by keeping the tanks full.
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Old 17-09-2014, 04:37   #64
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Re: Fuel Polishing System Installation

OK. Anyone else have some pictures or descriptions of a fuel polishing system installed on their boat they'd like to share? Power boats are welcome too. After all, I got the idea for mine off CF two years ago.

Ken
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Old 17-09-2014, 05:07   #65
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Re: Fuel Polishing System Installation

As I have learned from many fuel oil schools in the Navy......It is best to keep things simple with diesel. Additives are a band aid at best....regardless of what information is put out there to the public. The best way to keep fuel from going bad is to burn it off as you buy it. Idle boat tanks will accumulate water and carbon build up. For those who don't have the option of removing the fuel before winter lay up, then polishing fuel is a safe way to remove water and loose carbon build up in fuel tanks. We used to make a our own portable polishing/filtering systems built onto 1/2' piece plywood with a 1/2 hp Jabsco pump with nitrile impellers. We would mount a separator and primary filter with all the associated fittings and tubing. The thing only weighed about 25 pounds and we would take it from boat to boat that were in lay up. No need to "over engineer" a simple system.
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Old 17-09-2014, 06:15   #66
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Re: Fuel Polishing System Installation

Quote:
Originally Posted by Maine Sail View Post
Another expert has spoken..... Please oh please explain for us mere mortals how an empty tank on the second floor of an uninsulated barn with the tank vent physically piped outdoors, just like on a boat, is any different than the empty tank on my boat less than 4' away experiencing the same temps, weather and temp swings..? Oh and please do so scientifically.....

Sorry I am all set on the snake oil...
I wouldn't go so far as to say it is all snake oil (some is and claims are often filled with puffing); I've done testing of biocides and salt water/acetic acid corrosion and found that some are effective and some are not. I tend to mention Valve Tech, Biobor, Stabil, and Startron because they do positive things I've been able to measure in side-by-side testing. I'm planning to do a series (gas and diesel) this winter on oxidation/sludge stability based upon ASTM methods. I suspect some will perform and many will do nothing. Do you need additives? As others have mentioned, they are generally band-aides for a separate problem.

Vapor space corrosion? A very real problem in shore-side tanks. I've seen tanks with holes in the roof you can jump through. But boats slosh and the oil film stops that, or at least I've never heard of it being a problem.

Acetic acid. This is primarily a problem if ethanol has gotten in the fuel (can happen, since trucks and pipes are sometimes shared with e-10) and bugs degrade it. Check the pH of the water your polishing systems removes; it should be 6-7, but I've seen it as low as 3.7, which is nearly vinegar. That is probably the largest internal corrosion threat.

Full vs. empty. I think I'll start some bottles both ways, with vents to scale. People have made arguments both ways using a lot of big words with no actual calculations. I'd rather just run a test. I do know that with gasoline there is no question; full is MUCH better in terms of oxidation and water, and with e-10, either a closed vent or a silica gel filter is a good idea, not just for water, but also in terms of evaporation reduction and retained volatiles. The vent filter helps keep the octane up. But diesel could be different. I was able to recreate condensation repeatably, but always with ~ 70% full containers. We'll see and I will post pictures.

---

And though your barn test sounds valid for a boat out of the water, I'm not sure the same is true for boats that winter in the water. The humidity, particularly in the spring, near vents a few feet above the water is over 100% (heavy fog and heavy dew every night). I've seen the condensation in the hose and in the first carbon vent filter I tested (the carbon actually became soaked with water). This is why the EPA speced carbon for boat filters (they tested in a lab, not near the water). I believe boats stored on land and trailer boats are a considerably different case from those wintering in the water, just as boats under a tarp in the snow have different issues from those in warmer places.

Very complicated, and very difficult to predict. I will need to place those containers in several different environments (in vented shed, and near water with guarded vent).
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Old 17-09-2014, 07:08   #67
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Re: Fuel Polishing System Installation

Quote:
Originally Posted by thinwater View Post
I wouldn't go so far as to say it is all snake oil (some is and claims are often filled with puffing); I've done testing of biocides and salt water/acetic acid corrosion and found that some are effective and some are not. I tend to mention Valve Tech, Biobor, Stabil, and Startron because they do positive things I've been able to measure in side-by-side testing. I'm planning to do a series (gas and diesel) this winter on oxidation/sludge stability based upon ASTM methods. I suspect some will perform and many will do nothing. Do you need additives? As others have mentioned, they are generally band-aides for a separate problem.

Vapor space corrosion? A very real problem in shore-side tanks. I've seen tanks with holes in the roof you can jump through. But boats slosh and the oil film stops that, or at least I've never heard of it being a problem.

Acetic acid. This is primarily a problem if ethanol has gotten in the fuel (can happen, since trucks and pipes are sometimes shared with e-10) and bugs degrade it. Check the pH of the water your polishing systems removes; it should be 6-7, but I've seen it as low as 3.7, which is nearly vinegar. That is probably the largest internal corrosion threat.

Full vs. empty. I think I'll start some bottles both ways, with vents to scale. People have made arguments both ways using a lot of big words with no actual calculations. I'd rather just run a test. I do know that with gasoline there is no question; full is MUCH better in terms of oxidation and water, and with e-10, either a closed vent or a silica gel filter is a good idea, not just for water, but also in terms of evaporation reduction and retained volatiles. The vent filter helps keep the octane up. But diesel could be different. I was able to recreate condensation repeatably, but always with ~ 70% full containers. We'll see and I will post pictures.

---

And though your barn test sounds valid for a boat out of the water, I'm not sure the same is true for boats that winter in the water. The humidity, particularly in the spring, near vents a few feet above the water is over 100% (heavy fog and heavy dew every night). I've seen the condensation in the hose and in the first carbon vent filter I tested (the carbon actually became soaked with water). This is why the EPA speced carbon for boat filters (they tested in a lab, not near the water). I believe boats stored on land and trailer boats are a considerably different case from those wintering in the water, just as boats under a tarp in the snow have different issues from those in warmer places.

Very complicated, and very difficult to predict. I will need to place those containers in several different environments (in vented shed, and near water with guarded vent).
I was referring to the "additive" for an empty tank that is needed to prevent vapor space corrosion.....

Quote:
Originally Posted by Aloha_float View Post
Put the tank outside for that test. Inside the barn isn't a real fair test.

Corrosion in vapor space is from acetic acid.

All else is misleading...full tanks help prevent vapor space corrosion

There are additives designed specifically to handle vapor space corrosion

Read the battelle report
We are talking about a tank that has been empty now for almost two years with zero measured internal moisture, (tanks walls physically wiped with tissue paper and it comes out bone dry), and measured on numerous occasions, does not need an additive to prevent "vapor space corrosion".... That is what I was referring to as the snake oil....


FWIW my barn is less than 350' from the foggy Maine ocean. We regularly see humidity in the 90% - 99% range and the barn sees temp swings of as much as 70F per day. This morning at 7:30 it was 44F in the barn two minutes ago it was 81F with the sun beating on the black asphalt roof. Humidity is currently 82% and outdoor temp 59F. This is a 37 degree temp swing, at the tank, in about 2.5 hours.. Being at the head of the bay the summer and winter humidity levels can be pretty high compared to just a mile inland.. The temp swings of my barn are actually wider than I see on my covered boat due to the black asphalt roof of the barn vs. a white shrink cover on the boat. These changes occur pretty rapidly due to the lack of insulation on the second floor. I also have stone pavers the tank sits on to appease one reader. It made no difference in tank moisture as I have yet to get any..

The point of that test is to compare, and have easy access to, a tank "like" what my tank on the boat sees on an average winter. Here in Maine only a few boats store in-water.

Last winter was the first winter I left the tank mostly full but only because of the testing of the H2Out you sent me.. It will again be empty this coming winter.

BTW the beads on the H2Out still have not changed color, at least to my eye.

FWIW I fully went into this test expecting to see some light moisture on the tank walls, but I have not, at least not yet.....
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Old 17-09-2014, 10:42   #68
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Re: Fuel Polishing System Installation

Quote:
Originally Posted by thinwater View Post
Full vs. empty. I think I'll start some bottles both ways, with vents to scale. People have made arguments both ways using a lot of big words with no actual calculations. I'd rather just run a test. I do know that with gasoline there is no question; full is MUCH better in terms of oxidation and water, and with e-10, either a closed vent or a silica gel filter is a good idea, not just for water, but also in terms of evaporation reduction and retained volatiles. The vent filter helps keep the octane up. But diesel could be different. I was able to recreate condensation repeatably, but always with ~ 70% full containers. We'll see and I will post pictures.

---

And though your barn test sounds valid for a boat out of the water, I'm not sure the same is true for boats that winter in the water. The humidity, particularly in the spring, near vents a few feet above the water is over 100% (heavy fog and heavy dew every night). I've seen the condensation in the hose and in the first carbon vent filter I tested (the carbon actually became soaked with water). This is why the EPA speced carbon for boat filters (they tested in a lab, not near the water). I believe boats stored on land and trailer boats are a considerably different case from those wintering in the water, just as boats under a tarp in the snow have different issues from those in warmer places.

Very complicated, and very difficult to predict. I will need to place those containers in several different environments (in vented shed, and near water with guarded vent).
Concerning gasoline and full tanks -- this is a totally different question. Gasoline is an inherently unstable substance, and suffers from exposure to air. A full tank prevents not condensation, but gasoline breaking down in the presence of oxygen. Diesel fuel is not subject to this effect.

Concerning diesel tanks and condensation, lets drive a stake through the heart of this hoary old wive’s tale – about keeping your tanks full to avoid condensation -- once and for all.

The theory is that as the temperature rises and falls, your fuel tank “breathes” through its breather pipe, “breathing in” moist air, which then cools off inside your tank, causing water to precipitate out of the air and go into the tank.

First problem with this theory is that the volume of this “breathing” is very small – every boat will be different, but a fuel tank buried somewhere in the bilge will always have a smaller temperature range than the outdoors. If the temperature range in the outdoor is say 15 degrees C (that would be a big range – a sunny winter day with a cold night), then what will the range be inside your tank? In most boats, the tank will be influenced more by the water temperature, which hardly varies according to time of day, than by ambient air temperature. But let’s take a high number – say 5 degree C – what would be the volume of air “breathed” in and out of your tank? At 20C, the coefficient of expansion of air is about 0.003/degree. That means that air will contract or expand by 0.3% for every degree C it cools or warms. So a 5 degree range would create 1.5% “breathing” as a percentage of volume. For a 500 liter tank which is almost empty, that would be 7.5 liters of air.

The second problem with this theory, is that condensation occurs only when the temperature of the air falls below the dew point, and the amount of condensation which forms is only that volume of water vapor which is the difference between that volume of water which your mass of air was holding at the high temperature of your range, and that volume of water which your mass of air was able to hold at the minimum temperature of your range. Since the saturation vapor density of water is about 18 grams/m3 at 20C, your 7.5 liters of air was capable of holding the gigantic quantity of 0.135 grams of water. That’s 2.7 drops (at 20 drops per ml). At 15C, after a temperature drop of 5C, your 7.5 liters of air is capable of holding 13 grams/m3. So if your 7.5 liters of air which your tank “breathed” in was fully saturated at 100% humidity, then a 5C drop in temperature will result in 0.04 grams of dew – which is less than a single drop. And that’s the WORST case – no dew at all will be formed if the humidity is less than 90-something percent. Since 100% humidity does not occur every day, and in most places which are not tropical rain forests does not occur very often, you will not very often get any condensation at all.

(a) The third, and really fatal problem to the “keep your tanks full to avoid condensation” theory is that your tank “breathes” out in the daytime – when the temperature of the tank goes up. It “breathes” in at night as it cools off. But it’s the cooler air at night which contains the least volume of water! And the cooler air breathed in at night has no place to cool off!!! This means that the temperature range to which the breathed in air is exposed is far less than the temperature range the tank experiences. How much less? I don’t know, but it can’t be much more than 25% of the total range. That reduces the theoretical maximum amount of condensation, based on the assumption that all air is breathed in at 100% humidity, to .0.01 grams of water, or ¼ drop. That would require 25,000 days or more than 68 years, to accumulate one cup (250ml) of condensation, assuming none of it evaporated back in the meantime.

So in summary:

(a) The maximum theoretical amount of condensation in a nearly empty 500 liter fuel tank undergoing a 5C daily temperature change is 0.04 grams per day.

(b) The maximum theoretical amount of condensation if far lower, since nowhere outside a tropical rain forest is 100% humidity a common event. In many places in the temperate zone, humidity of over 90% will never occur in the winter unless there is a rain storm going on at that very moment. So in many places, the maximum theoretical amount of condensation will be zero – nil – goose eggs. Let’s take a rainy place like Portland, OR – how many days do you have 100% humidity? Even there your total yield of condensation would be half, I guess, or less, than what is predicted by assuming 100% humidity every day.

(c) AND LASTLY, the maximum theoretical amount of condensation assumes that the tank “breathes” in warm air at 100% humidity and at the maximum of the temperature range. This does not occur, since the tank is breathing in when the temperature is lower, not higher.

Applying factors (c) and (d), we can see that it would take probably 120 years to make a cupful of condensation in a rainy place, in a nearly empty 500 liter tank.

So people: leave your tanks better nearly empty in the winter, rather than full. Can it be a good think to store fuel which is not being used for long periods of time? Wouldn’t you rather have fresh fuel, when you need it?
Water in your tanks doesn’t come from condensation – it comes from water which was already in the fuel precipitating out (and the more old unused fuel you have onboard, the more of this kind of water you will get), or more likely, from a leak in your deck filler, or from water which gets down your tank vent. Better to concentrate on these factors, than waste your time on these old wives’ tales.


P.S. – wide range of temperature occurs when it is sunny in the daytime and clear at night. When it is rainy and humid, the range of temperature is less. This even further reduces the amount of condensation, but I think the stake is driven in far enough already.
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Old 17-09-2014, 11:24   #69
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Re: Fuel Polishing System Installation

Re Mainesail:

Nope, I see no reason for a vapor space additive. And while they do exist, they are generally for high temperature operations. A total waste here, in the absence of a problem.

Condensation is extremely variable. Some weeks I can recreate it, when the swings are just so (typically early spring), other wise, not the rest of the year. And I've never seen an MT tank draw water, and I've been in lots of them. Mostly the oil will become saturated, but not settle any water.

I have seen some color change with testers further south where the total humidity is greater for longer. Likewise, I suspect the condensation issues are all worse further south. 100% humidity in Maine at 75F does not compare to consistent 100% humidity at 90-100F; the total amount of water in the air goes up rapidly with temperature, as does the rate of water absorption.

Still, the color change is slower than most predicted. It seems there is some regeneration taking place. Also remember that the color change starts when the adsorbent is only ~ 30% spent. So while the effect is probably small, the cost (if you change only as needed) is very small beans indeed.

Re Dockhead:

Yes, gasoline and diesel are different. However, diesel IS subject to air oxidation (that is how the ASTM tests are run!), just slower. If you expose one bottle to air (1/16" hole) and seal one, and come back in 3 months, you will see a clear difference. Add copper coupons (Cu catalyzes polymerization) the effect is more rapid. Zn also does this, a reason to NEVER use galvanized pipe with fuel (its in the code).

As for discussion of moisture increase in fuel due to atmospheric exposure, suffice that it can occur, I've reproduced it, and some of your assumptions are simply not correct. The refiners know this and they've spent real money studying this. Condensation on the underside of the roof of large fuel tanks is a well known fact, not meriting discussion of it's truth. Interview the API tank inspector of your choosing. Sections of the code are devoted to the problem. whether this applies to boats is a complelty different question, since size matters.

Basically, you assume diesel is not hygroscopic; this is false, as it is and does absorb water while well above the dew point, just as e-10 can draw water from the air. The process is slower, but it is real. And while e-10 can hold 0.4% water in solution, diesel can hold only ~ 20-50 ppm, depending on additives and temperature. These small amounts can precipitate when the oil temperature swings (less is soluble in the cold--freeze diesel that is saturated at 70F and it will fog with micro drops). And so one oversimplification renders the mathematical argument inconclusive.

As I have said, this is a tiny effect, and I believe that 99% of water in diesel stories start with a rain leak.

That said, the practical answer is for others to repeat this testing. This is an invitation. Take several bottles. Place metal corrosion cupons in each jar.
* seal one
* give one an 1/8" x 12" breather hose
* give one an 1/8" x 12" breather hose with a tiny (to scale) silica gel filter
Wait for several months and look at the results. Measure the water content of each sample by Karl Fischer.

I have done this several times, with minor variations. The base results is this:
* bottle 1 does not change
* bottle 2 shows significant corrosion and is saturated with water (50 ppm-100ppm). there may be free water, but less than 1 good drop.
* bottle 3 is somewhere in between, closer to sealed. water is still low, but because of oxygen, there is some corrosion.
As a chemical engineer I'm willing to admit that I don't know the exact chemistry as it is very complex and variable. In addition to reducing water, the filters also inhibit oxygen exchange. What I do know is that fuel tanks, large and small, do better if venting is restricted and the oil is kept super dry. I know this from practical, repeated laboratory and field testing.

I also know that additives can help, but you must KNOW which additive performs the specific task required; too many vendors are unreliable sources of information. And it is far from clear that a well maintained tank needs any treatment. In theory, it should not.

----

Is a 10% tank better than a 90% tank? I'm going to do some practical testing because I'm pretty sure that while both can be good, empty is probably the safer bet for most folks. Yup, they'll have 5 gallons of saturated, oxidized fuel in the tank, but 90 gallons of fresh will solve that. But we'll see. I did a bunch of testing on e-10 first, because that's what I've got; self-interest! I tested multiple adsorbents and multiple additives and learned some useful things. This is just idle curiosity.
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Old 17-09-2014, 17:03   #70
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Quote:
Originally Posted by thinwater View Post
Re Mainesail:

Nope, I see no reason for a vapor space additive. And while they do exist, they are generally for high temperature operations. A total waste here, in the absence of a problem.

Condensation is extremely variable. Some weeks I can recreate it, when the swings are just so (typically early spring), other wise, not the rest of the year. And I've never seen an MT tank draw water, and I've been in lots of them. Mostly the oil will become saturated, but not settle any water.

I have seen some color change with testers further south where the total humidity is greater for longer. Likewise, I suspect the condensation issues are all worse further south. 100% humidity in Maine at 75F does not compare to consistent 100% humidity at 90-100F; the total amount of water in the air goes up rapidly with temperature, as does the rate of water absorption.

Still, the color change is slower than most predicted. It seems there is some regeneration taking place. Also remember that the color change starts when the adsorbent is only ~ 30% spent. So while the effect is probably small, the cost (if you change only as needed) is very small beans indeed.

Re Dockhead:

Yes, gasoline and diesel are different. However, diesel IS subject to air oxidation (that is how the ASTM tests are run!), just slower. If you expose one bottle to air (1/16" hole) and seal one, and come back in 3 months, you will see a clear difference. Add copper coupons (Cu catalyzes polymerization) the effect is more rapid. Zn also does this, a reason to NEVER use galvanized pipe with fuel (its in the code).

As for discussion of moisture increase in fuel due to atmospheric exposure, suffice that it can occur, I've reproduced it, and some of your assumptions are simply not correct. The refiners know this and they've spent real money studying this. Condensation on the underside of the roof of large fuel tanks is a well known fact, not meriting discussion of it's truth. Interview the API tank inspector of your choosing. Sections of the code are devoted to the problem. whether this applies to boats is a complelty different question, since size matters.

Basically, you assume diesel is not hygroscopic; this is false, as it is and does absorb water while well above the dew point, just as e-10 can draw water from the air. The process is slower, but it is real. And while e-10 can hold 0.4% water in solution, diesel can hold only ~ 20-50 ppm, depending on additives and temperature. These small amounts can precipitate when the oil temperature swings (less is soluble in the cold--freeze diesel that is saturated at 70F and it will fog with micro drops). And so one oversimplification renders the mathematical argument inconclusive.

As I have said, this is a tiny effect, and I believe that 99% of water in diesel stories start with a rain leak.

That said, the practical answer is for others to repeat this testing. This is an invitation. Take several bottles. Place metal corrosion cupons in each jar.
* seal one
* give one an 1/8" x 12" breather hose
* give one an 1/8" x 12" breather hose with a tiny (to scale) silica gel filter
Wait for several months and look at the results. Measure the water content of each sample by Karl Fischer.

I have done this several times, with minor variations. The base results is this:
* bottle 1 does not change
* bottle 2 shows significant corrosion and is saturated with water (50 ppm-100ppm). there may be free water, but less than 1 good drop.
* bottle 3 is somewhere in between, closer to sealed. water is still low, but because of oxygen, there is some corrosion.
As a chemical engineer I'm willing to admit that I don't know the exact chemistry as it is very complex and variable. In addition to reducing water, the filters also inhibit oxygen exchange. What I do know is that fuel tanks, large and small, do better if venting is restricted and the oil is kept super dry. I know this from practical, repeated laboratory and field testing.

I also know that additives can help, but you must KNOW which additive performs the specific task required; too many vendors are unreliable sources of information. And it is far from clear that a well maintained tank needs any treatment. In theory, it should not.

----

Is a 10% tank better than a 90% tank? I'm going to do some practical testing because I'm pretty sure that while both can be good, empty is probably the safer bet for most folks. Yup, they'll have 5 gallons of saturated, oxidized fuel in the tank, but 90 gallons of fresh will solve that. But we'll see. I did a bunch of testing on e-10 first, because that's what I've got; self-interest! I tested multiple adsorbents and multiple additives and learned some useful things. This is just idle curiosity.
Why do you say I assume that diesel is not hydroscopic? I'm struggling to see where we disagree.

On the contrary, I'm saying that 10 gallons of saturated, oxidized fuel is a hell of a lot better than 90 gallons of it. And when water starts to precipitate out of fuel, wouldn't we rather have the water which comes out of 10 gallons, then out of 90 gallons?

Where do we disagree?
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Old 17-09-2014, 18:06   #71
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Re: Fuel Polishing System Installation

God! all I want to know is do I keep my tank full or leave it empty when not being used? Is my fuel polisher I've spent a $1k on a good idea or will it damage the fuel? And do I use a fuel conditioner or not?
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Old 17-09-2014, 20:25   #72
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Re: Fuel Polishing System Installation

Quote:
Originally Posted by tedsherrin View Post
God! all I want to know is do I keep my tank full or leave it empty when not being used? Is my fuel polisher I've spent a $1k on a good idea or will it damage the fuel? And do I use a fuel conditioner or not?
yes - its a good idea - any preventative measure is a good idea

yes - use a conditioner -

I usually just leave the fuel in my tank and don't worry about it - I add fresh fuel in the spring and replace my filter - and clean my racor if it needs it - it hasn't needed it
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Old 17-09-2014, 21:20   #73
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Re: Fuel Polishing System Installation

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Originally Posted by Aloha_float View Post
yes - its a good idea - any preventative measure is a good idea

yes - use a conditioner -

I usually just leave the fuel in my tank and don't worry about it - I add fresh fuel in the spring and replace my filter - and clean my racor if it needs it - it hasn't needed it
Wonderful. I'll follow suit. Cheers.
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Old 18-09-2014, 03:41   #74
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Re: Fuel Polishing System Installation

Not to throw fuel on the fire so to speak. Despite the logic presented here about condensation on partial full tanks. I was taught on my Father's knee, that you keep fuel tanks full to prevent condensation in a tank, boat or otherwise. In my neighborhood even a small amount of water can form ice crystals which will clog filters, a bad thing when at sea in a storm. Also, when one's tanks are filled in the fall, the fuel price has never been less come spring, so I can run for an extended period of time before shelling out for the more expensive fuel. I use Power Service in my fuel as a conditioner, cannot say if it is effective, the point is to prevent a problem rather than deal with the after effects, it may be merely the placebo effect, but it makes me feel better and so far as I know, it hasn't hurt the engine performance. I also use an algaecide, and a centrifuge. I use the centrifuge as the fuel exits the tank, before it gets to the filters, so far it has worked well. I intend to post photos of my system, which is home built as soon as I get my engine out so I can take some good photos of the mount, pump, manifold etc... I should be done with my engine removal by the end of Sept. I have no interest in Power Service, I am only a customer.
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Old 18-09-2014, 05:02   #75
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Quote:
Originally Posted by Aloha_float View Post

yes - its a good idea - any preventative measure is a good idea

yes - use a conditioner -

I usually just leave the fuel in my tank and don't worry about it - I add fresh fuel in the spring and replace my filter - and clean my racor if it needs it - it hasn't needed it
Good advice!
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