Foggy fuel

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Joined
Oct 31, 2007
Messages
18,745
Location
USA
Vessel Name
Willy
Vessel Make
Willard Nomad 30'
I pumped samples of fuel (a pint to a quart) out of both my fuel tanks into one gallon plastic jugs .. the kind you buy purified water in. The fuel from my stbd tank was clear. But the fuel from the port tank is so foggy I can't see through 2 or 3" of it to the bottom of the jug. That's how I test for water but I can't see through the fuel where the water would be. I can look up under the bottom of the jug and see water .. even a drop. But I'm concerned about the cloudy fuel.

The cloudyness in the fuel is either water or stuff growing IMO.

PS I tried a search.

The question is;
1. If I run the cloudy fuel will the engine care?
2. Is the cloudy stuff water in some emulsified form or growing organisms? .. Or what?
 
Get a glass mason jar and pour the fuel in it. Let it settle and see what separates out.

I had one boat that had a water problem in the tank, the guy added some "fuel treatment" additive that actually was an emulsifying agent. The water was now suspended and it looked pink and cloudy. I unloaded the fuel, cleaned the tank and after a month or two the water separated to the bottom of the barrels I stored it in.

Put any treatment in the tanks??
 
Ski,
Yes. I almost always add a good dose of StaBill. So I'm sure I'm covered there but I used to put BioBore in the fuel too. I don't think I've done that for a long time. And the boat's been idle for the last 2.5 years. Tanks new aluminum 8 years ago.

On the way home from the boat (today) I thought I should have put some BioBore in the plastic jug w the cloudy fuel to see if the cloudyness would be affected. But the BioBore is probably effective at keeping stuff from growing but once it's grown it probably won't get rid of it .. just kill it. ???

The tank's about half full. Perhaps a good strong dose of BB & SB and filling the tank diluting it to 1-1 would take care of the problem .. if indeed it is a problem. Untill I know it's not I'll consider it a problem.

Unless we go north this summer (there's been talk) we really won't need the second tank but the "problem" most likely won't get any better w/o some action by me. So I need to burn it up, get rid of it or fix it.
 
Might I suggest "Kolor Kut" . I use it regularly on tank before and after fueling. It is a water indicator. Smooth it on your measuring stick end and stick it in your tank it will turn from yellor paste to bright red if water is present emulsified or not.

dan
 
Eric

For peace of mind maybe a tank cleaning company could be engaged and they can keep the fuel.
 
Eric,

You have an analytical laboratory not too far from you called Friedman & Bruya. They are the only lab on the planet that I would call to help with a problem like yours. Their address and phone number is as follows:

3012 16th Avenue West
Seattle, WA 98119
(206) 285-8282

I have no affiliation with them other than being a customer for the last 25 plus years.

I recommend talking to them about your discovery and possibly have them analyze a sample (they will provide proper sample containers).

Good luck!
 
The makers of my current choice of "snake oil","Fuelmaster" warn that if you overdo the dosing you can get a gelling effect, though they advise a doubled dose for treating problems as distict from maintenance. They like users to mix the dose into 10L or a couple of gallons of fuel, add that, then refuel, so as to ensure proper distribution. Any similar advice from your "snake oil" provider? Could fuel age be a factor?
 
Eric--- I wouldn't mess around with possible solutions that are just guesses. I'd take a sample of the cloudy fuel to the company Ray recommends and see what they have to say.

If I couldn't do that for some reason I'd get all the fuel out of the tank, fill it with fresh fuel and whatever fuel additive you like (we use Biobor and Lubribor) and sell or give the cloudy fuel to somebody who runs diesel equipment in Concrete. Or pour it on a patch of weeds you want to get rid of.
 
WOW,
Kolor Kut to pour it on weeds.
Yes Bruce I've not over done the additives.
Tom, Ray and Marin it could come to that.
I was actually looking for someone that had the cloudy fuel problem and did the research or enacted a cure that worked. I like the Kolor Kut as it provides a simple answer to one question .. is it water? Tom my tank isn't dirty .. just the fuel in it. but removing the fuel is a good option it appears. Would just need containers. It's probably over $100 worth of fuel. That would be an acceptable solution. Just throw the problem away. Simple.
 
From my limited experience with water in fuel (aviation gasoline), it sinks to the bottom and makes slippery clear blobs. I've never seen cloudy fuel ever, either gasoline or diesel.

We've never had to use a water dispersant in any of our engines, gasoline or diesel, automotive, aviation, or marine, so I don't know what fuel with water in it looks like with a dispersant added to it.

I suppose if the fuel were REALLY agitated up, like on a paint mixing machine, you could get the cloudy effect for awhile with water in the tank but then the water bits would sink to the bottom and connect into slippery clear blobs again.

Since one tank has it and one doesn't, this would indicate a tank problem rather than a fuel problem if you took on both tanks of fuel at the same time

"Bugs" (bacteria) grow in fuel at the water/fuel interface. As I understand it they live in the water and feed on the fuel. So it sounds like they'd be concentrated in a specific place or layer in the fuel, not scattered all through it.

When the bugs die, they sink to the bottom of the tank, they don't remain suspended in the fuel unless the fuel is really agitated up. But even then, like water, they'll head for the bottom of the tank when the agitation stops.

We don't use Stabil in diesel fuel so I don't have a clue how it behaves or might behave over time.

So again, I would be off to the fuel analysis company in Seattle with a sample of what I had. There are too many reasons to think that whatever it is isn't what one might think it is. To me, your cloudiness isn't acting like water and it's not acting like bugs. Time for the lab folks who know what they're doing, in my opinion.

Either that or just get it all out of there and start with fresh fuel and see what happens.
 
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There are 2 typed of goop folks can dump in their fuel tanks to clear water.

An emulsifier will suspend the water , so your fuel filters can remove it , just keep draining them.

The other is a DE emulsifier which causes the water to drop to the tank bottom.

This is what to use with a marine fuel tank with a sump, or low point drain.

Most folks have a fuel box , not a marine fuel tank, so the emulsifier is about the only solution.

I have seen boats where it was possible to slip a plastic hose down the fill and get it to the tank bottom.

Then the boat is healed with garbage bags full of water to concentrate the water to one side and a de emulsifier can be used.The water sinks ,overnight .

Remember turning the hand pump may get the pick up tube in a deeper water spot.
 
All great information from others above, I would caution over treating (a good dose) or using multiple solutions (more is better), bottom line is you have an amazingly efficient boat and the fuel is staying in there way too long.
 
Had that problem once and just ran on low fuel to cycle it through the filters faster and added only as much as I used. A few cycles later it was jewel red. Never reoccurred.
 
dumped some water on the table and while cleaning up the mouse lost the post.

FF and Marin,
Very helpful thoughts on this issue that's been very helpful to me.

Re the above I'm going to think it's not water in the fuel. I agree. It's almost impossible that it could be water. FF wrote ; "I have seen boats where it was possible to slip a plastic hose down the fill and get it to the tank bottom." Not my boat either but I can go down through a hole in the top of the tank. I have a pump, hose and copper pipe (1/8") that I put down the dipstick hole and maneuver it where I want. Usually to the lowest corner. If any water is in the tank (even a drop) it will get pumped up into my plastic jug. I need to run the pump at least long enough to transport the water from the fuel tank bottom to the jug. Even a drop of water I can see through the bottom of the jug. I haven't done it but I'll bet I could put a drop of dyed water in the tank .. pump it out and identify it through the bottom of my plastic jug. I've not had a water problem over the years. Usually it's just a drop or two or none at all but once a gallon or so leaked into the port tank (the tank in question now) and I promptly pumped all of it out right away.

So much for water. Must be things growing in the fuel, bugs as Marin says and they must be alive as they are not on the bottom of the tank. Before they get there I need to pump them, (suspended in the fuel) OUT into 5 gallon containers so we can carry them up the ramp at high tide.

Marlinmike,
For an 8 ton 30' boat not really very efficient I'd say. About average. 25% of that 8 tons is in ballast and weight is the enemy of efficiency. But compared to the average trawler she seems efficient because she burns less fuel. But she burns less fuel mostly because she's smaller and has a FD hull. I still like like one gph. And if I want or need a lower burn dropping down to say 5.25 knots from 6 perhaps I could drop the burn to 1/2 gph. Like if I decided to take Willy to Hawaii.
 
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"And the boat's been idle for the last 2.5 years."??? Going for a cruise occasionally would be more fun the carrying five gal buckets of fuel up the dock ramps. :)
 
Tom my tank isn't dirty .. just the fuel in it.

You don't know that since you don't even know what's in the fuel. And your tank is at best some small degree dirty from the fuel. Getting that last amount of fuel completely out might require some work. I would personally still want to know what is in the fuel.
 
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Eric,

I just read through the thread. You say that it's a $100 problem. That about eliminates my suggestion of running a sample through the lab because the sample cost could be similar. Marin's weed-control solution is starting to look better all the time....just don't let the EPA catch wind of it! We live in a funny world.
 
If you have bugs in your fuel, you have to have, or have had water as well. If you take a sample to the lab mentioned in post number 6, you might be better armed to deal with any reoccurrence.

Here's some stuff I came across that might be helpful.

Diesel Bug Explained
Diesel Bug (Bacteria Contamination of Diesel)

Bacteria in diesel is a well known problem to anyone who works with diesel engines, so what is this bug and why does it contaminate diesel?
Diesel is an organic fuel so it provides an ideal environment for microscopic fungi, yeast and bacteria to feed and grow.

This environment provides:

dissolved water for germination
carbon for food
oxygen and sulphur for respiration
trace elements for growth and propagation.
As many as twenty seven (27) varieties of bacteria are responsible for the majority of problems with diesel engines and their performance. There are many differing types of bacteria which can infect systems and form bio-films on steel surfaces. Accelerated corrosion can also occur wherever the bio-film settles, usually in pits or crevices. Unlike general corrosion, it is an attack on a very specific area.

It is very difficult to determine when a system is first contaminated, but once contaminated diesel enters the fuel system, it is very difficult to eradicate.

Diesel bug can originate from the air or moisture, or during tank filling and/or expansion and contraction of storage tanks, the bacteria cover themselves in a protective film (slime) to protect against biocides and can lie dormant in the minute crevices of the metal, rubber and polyurethane coatings of the fuel tanks and fuel systems.

Then, when water is present (a droplet is a lake to a microbe) and the environment hits the right temperature range, they begin reproduction in the area of fuel/water interface.

Microscopic in size, they can develop into a mat easily visible to the naked eye very rapidly. A single cell, weighing only one millionth of a gram can grow to a biomass of 10 kilograms in just 12 hours, resulting in a biomass several centimetres thick across the fuel/water interface.

Each species has its own characteristics:

BACTERIA
Bacteria utilise hydrocarbons and reproduce asexually by binary fission; swelling in size as they feed, they then separate into two cells. In this way, microbes double their numbers every 20 minutes, one spore converting to 262,144 in 6 hours.

SULPHATE REDUCING BACTERIA (SRB)
SRB's are a specific group of bacteria utilising simple carbon, not hydrocarbons, and require the activity of other microbes in a consortium. Aerobic (in the presence of oxygen) or anaerobic (without oxygen) bacteria have a combined effect. The aerobic bacteria (sulphate oxidising) create a film to consume the oxygen first. This allows the anaerobic (sulphate reducing) bacteria to thrive.

SRB's reduce sulphates and produce hydrogen sulphide (a lethal gas). They are directly involved with many microbial corrosion reactions and can cause sulphide souring of stored distillate products. Their action changes the Ph creating an acidic environment, conducive to accelerated corrosion. They attach themselves to the steel as a film and go to work. They derive their nutrition from the surrounding environment and multiply. They are particularly difficult to deal with and produce a sludgy by-product with a strong sulphur odour similar to rotten eggs (hydrogen sulphide).

IRON REDUCING BACTERIA
These also contribute to corrosion, eating steel and reducing ferrite to an oxide through a chemical reaction.

YEASTS
Yeasts prefer acidic environments, such as produced by SRB's. They bud on the parent cell, eventually separating. Reproduction takes several hours.

FUNGUS
Fungi grow in the form of branched hyphae, a few microns in diameter, forming thick, tough, intertwined mycelia mats at fuel/water interfaces.

All of these can and do cause damage to the fuel system.

PREVENTION
Maintain the fuel system by draining water very regularly, keep the tank as full as possible, (especially over-night) and try to ensure your supplier maintains his system well.

CURE
Clean the entire system with a cleaning agent available from or recommend by your diesel supplier.





Via iPhone.
 
Cafesport- Thank you for posting that great explanation of the bugs that can grow in diesel (and jet) fuel. It's a subject a lot of people, including me, know just enough about to be wrong most of the time.:)
 
Was the fuel in the two different tanks from different fill ups? If you bring the fuel in the house or leave in the sun to warm, does it become less cloudy?

Cloudy fuel is usually water. 100 ppm is allowable by the ASTM standard. 200ppm will show as cloudy. anything more than that will generally precipitate out and you'll find free water at the bottom.

I'd start with Kolor-Kut on a stick to check for free water. Then hit it with a biocide. I'd then probably run it through a set of fresh filters. Check the bowl or water petcock every once in a while and maybe change them early.
 
I picked up 150 gallons of diesel in the bahamas. A few days later I noticed the fuel in the racor looked black. I drained out a quart and after two weeks the fuel is still exceptionally dark although I can see through it if I hold it up to sunlight. There is nothing on the bottom of the jar. Engine runs fine.
 
Now I'm overwhelmed but Northern Spy hints of some good action I may take.

We always fill both tanks at the same time.

Where do you suppose I can get some Kolor-Kut? Now I think I need to do that. Visible "free water" is not apparent. But if there's water there will probably be bugs as well re what Cafesport presented. I'd say he's our bug man from here on.

I think I'll check for water as NS has suggested. Then extract the fuel and replace it w new including StaBill and BioBore. Then run changing the filters often and then less often depending on the contents of the extracted filters.

Ray thanks for the heads up and I was thinking similar.

meridian,
We must have different problems .. mine has a color mostly like farmer type apple juice. Amber. Nothing like black. I'm fine w a thread highjack to sort out Terry's black plague. I yeild the floor .. or tank .. or whatever.
 
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I got my Kolor Kut at the bulk fuel station in town. Any good farm store would likely have it. A tube will last a lifetime. Unless you get it wet...
 
Cloudy fuel is usually water. 100 ppm is allowable by the ASTM standard. 200ppm will show as cloudy. anything more than that will generally precipitate out and you'll find free water at the bottom

Spy--- Are you saying that it's possible for water to become and remain suspended in fuel that is just sitting there for long periods of time, as opposed to the particles going to the bottom and combining to form the clear, slippery "blobs" I'm used to seeing when checking airplane tanks for water?

I'm not arguing that you're wrong. I'm just curious if my own assumption has been.:)

Thanks,
 
It usually takes some form of mixing. Don't think gasoline will go cloudy, just the lower grades. I'm not at work right now do I don't have access to API or ASTM standards. I only have diesel grades of my reference material at home.

Diesel has what is know as a cloud point, but that is for the paraffin waxes precipitating at really cold temperatures.
 
Spy--- Are you saying that it's possible for water to become and remain suspended in fuel that is just sitting there for long periods of time, as opposed to the particles going to the bottom and combining to form the clear, slippery "blobs" I'm used to seeing when checking airplane tanks for water?

I'm not arguing that you're wrong. I'm just curious if my own assumption has been.:)

Thanks,

There are two types of water in diesel, Water in Solution and Free Water. The water in solution typically drops. Due to the difference in chemical composition it dissolves. However, free water will turn the diesel to the hazy color. Something is holding the water in suspension.

Note also diesel fuel holds more water than gas because of it's nature.

Here's a good discussion of water in diesel, having nothing to do with boating but from Equipment Today.

Water in Diesel Fuel Can Wreak Havoc in Engines
 
When I had a water ingress problem, I stored it in containers until I could find a place to dispose if it. Most of it settled out, but the fuel remained cloudy.
 
When I had a water ingress problem, I stored it in containers until I could find a place to dispose if it. Most of it settled out, but the fuel remained cloudy.

So this leads to a question regarding Eric's situation. If each tank has its own fill cap, is it possible that the one with the cloudy fuel has a cap leak or bad seal or something that allowed rainwater to seep into the tank over all this time?

Of course, if the boat was under cover then it's not a valid possibility.
 
So this leads to a question regarding Eric's situation. If each tank has its own fill cap, is it possible that the one with the cloudy fuel has a cap leak or bad seal or something that allowed rainwater to seep into the tank over all this time?

Of course, if the boat was under cover then it's not a valid possibility.

I think a lot of things are possible and until it's too early to eliminate possibilities. There really are two choices. One is have someone come remove the fuel and clean the tank and move on, hoping it doesn't recur. The other is to try to figure out what it is, then how it happened, to correct whatever the underlying cause is. Testing for water is certainly a start toward that.

I know it seems like a lot of time and potentially money over a small amount and low value of fuel. But my concern would be the issue recurring and leaving him in a bad situation some time. Honestly, I don't know which route I'd take. Probably for me, pursuing the underlying cause. However, many times in my life I've come across problems that were fixed and no one figured out the cause. I was never comfortable but many went years and no problem cropped up again.
 
Well, I'm a big fan of finding out the cause of a problem. In medical cases it's get a picture (MRI) instead of speculating about what the cause of a back, nerve, etc. problem might be.

In this case of cloudy fuel I would have already called the lab Ray spoke of and made arrangements to get the cloudy fuel analyzed. Only when one knows exactly what they're dealing with can a cure be devised.

If the analysis shows it's water suspended in the fuel, then you know the problem to solve: how'd the water get into the fuel in that tank and not the other one?

If it's bugs, how'd they get into the tank and why are they doing what they're doing?

If it's an additive gelling up or whatever, well, you know not to use that additive or not to let it sit in fuel for that amount of time.

And so on.
 

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