NormanS
Well-Known Member
All the more reason for tanks to have sumps with drain valves.
Spare fuel cans
- Thread starter zoidberg
- Start date
All the more reason for tanks to have sumps with drain valves.
dom
Well-Known Member
It's rather a lot of parts per million though !! At a first pass, the diesel's water content must be kept below its saturation point to avoid engine damage. This saturation level can be as low as 40ppm for certain mineral diesels in cold weather, up to a whopping 2000ppm for FAME diesel in warm climates. Europe's EN 14214 allows FAME to contain up to 500mg/kg and the regular EN 590 allows up to 200mg/kg.
To cut to the chase, FAME inclusive diesel has a lower fuel stability, a heightened risk of deposit formation, increased solvency, a much higher water shedding point, and consequently a much higher potential for microbiological contamination (diesel bug). Moreover, one can have one's tanks scrupulously dry in summer, only for free water to appear on a cold day to nourish the bugs, poleaxe one's injectors, and whatnot
So for cans, I'd say keep them bone dry, OCD clean, and filled only with high-quality, known-grade, FAME-free fuel. And of course use it within the oil company's recommended lifespan.
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lw395
Well-Known Member
It's rather a lot of parts per million though !! At a first pass, the diesel's water content must be kept below its saturation point to avoid engine damage. This saturation level can be as low as 40ppm for certain mineral diesels in cold weather, up to a whopping 2000ppm for FAME diesel in warm climates. Europe's EN 14214 allows FAME to contain up to 500mg/kg and the regular EN 590 allows up to 200mg/kg.
To cut to the chase, FAME inclusive diesel has a lower fuel stability, a heightened risk of deposit formation, increased solvency, a much higher water shedding point, and consequently a much higher potential for microbiological contamination (diesel bug). Moreover, one can have one's tanks scrupulously dry in summer, only for free water to appear on a cold day to nourish the bugs, poleaxe one's injectors, and whatnot
So for cans, I'd say keep them bone dry, OCD clean, and filled only with high-quality, known-grade, FAME-free fuel. And of course use it within the oil company's recommended lifespan.
In practice, diesel bug is much rarer in cars running on forecourt diesel than it is in boats running on red.
Damage from water dissolved in EN590 diesel does not seem to be common in cars.
The general view seems to be that the electronic injectors of modern cars would be more vulnerable to these issues than the traditional type found on yacht engines?
Possibly the people who formulate forecourt diesel fuel have a tiny bit of knowledge between them?
maby
Well-Known Member
How much of that is down to the much faster turnaround of fuel in the tank of most road vehicles? Most boats have tanks that can hold hundreds, or even thousands of litres of fuel and the pattern of usage is such that the fuel can easily be there for a year or more. Our diesel SUV can hold less than 100 litres of fuel and that will get burned in a month or less.
chrishscorp
Well-Known Member
I have a 10L fuel can (metal) filled up at the start of the season out to the boat and poured in through one of those magic fuel filters thankfully... as it took out the water and the diesel bug growth that i presume occured over the winter months.
Stemar
Well-Known Member
Also the quicker turnaround at the filling station. I once managed a local filling station for a month or two. I used to order a tanker load - 23,000 litres - of fuel (2* 5* & diesel mixed load at least once a week or we'd run out, something that was frowned upon both by management and our customers. IIRC, we had five pumps, so not a big place at all.
dom
Well-Known Member
The same oil co.s supply forecourts and marine diesel, so there's clearly no knowledge difference. (BTW almost everything I have written was sourced from BP and Shell which provide tons of useful info upon request) The oil co.s in turn produce fuels depending on regulatory, environmental, engineering, and other considerations. The term "red" is functionally meaningless here as it pertains only to the duty status. Most red is not FAME-free.
Aside from that, auto fuel systems possess far more sophisticated than boaty ones, starting with the filler cap. If one keeps extraneous water out, ensures that the auto manufacturers are aware of the fuel constraints, properly maintains the system, and use the fuel reasonably quickly, then one doesn't expect any problems.
The marine environment is different, which is why many users, including the MoD, specify only FAME-free grades. Horses for courses and the big oil co.s can produce something suitable for most.
Not that FAME inclusive fuel is a massive hurdle for boat owners, most Continental Europeans are perfectly happy with it. It just requires more care to avoid the bug.
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lampshuk
Well-Known Member
To cut to the chase, FAME inclusive diesel has a lower fuel stability, a heightened risk of deposit formation, increased solvency, a much higher water shedding point, and consequently a much higher potential for microbiological contamination (diesel bug). Moreover, one can have one's tanks scrupulously dry in summer, only for free water to appear on a cold day to nourish the bugs, poleaxe one's injectors, and whatnot
So it sounds like the worst-case scenario is to buy diesel from a roadside fuel station somewhere warm - for example the Canaries (in my dreams), then sail back to the UK for the winter.
I used to regularly top up Drifter's 90-l tank with 5-gal cans of garage diesel (being a driver of a company car it seemed like a cheap way to get fuel) and dosed and checked the tank regularly. Never saw a drop of water come out, nor a hint of slime.
Then early this year I had a nasty scare with a really bad attack of pipe-clogging slime (like dark brown chewing gum) apparently churned up off the bottom of the tank. So now I'm very much a fan of MDL's low-FAME fuel, liberally dosed with anti-bug something or other.
In a quandary now, though: whether to ditch 70l of fuel before the winter, or top up to the brim to reduce condensation....
lw395
Well-Known Member
I don't think it pays to be vague about 'dosing with anti-bug something or other'.
Several different 'somethings' intended to work in different ways.
I would say the main thing would be to know that the bottom of the tank is clean.
dom
Well-Known Member
When did you treat your tank and was it a biocide? Not all diesel treatments are. Also were the tank and fuel lines properly cleaned?
My advice would be to use whatever handy device you have to take samples from around the bottom of your tank. Put them a clean jam jar for examination. Any gungy, cruddy, slimy, gooey stuff, or free water spells trouble.
Next check the filters with a magnifying glass for crud and check the filter bowl for water. Finally check the clarity of the diesel from a sample drawn higher up the tank.
If all good, you're probably fine to just leave the boat as it is; I would. If not, then remedial action will be required before layup to avoid a serious problem developing over the winter.
Feel free to start another thread on here if you have any concerns.
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Graham376
Well-Known Member
We've been using white exclusively for 12 years and part time for about 5 years previously, no problems so far. Boats in Europe use the same fuel as road vehicles and it's rare to hear of bug problems in Portugal and Spain, compared to reports I remember hearing in the UK. I never let our tank get too low so guess that some of the contents may well be 2 -3 years old but it starts and runs fine. A couple of years ago, I fed a pipe to the bottom of the fuel tank (no drain cock) and filled 2 x 5L water containers, no sign of water or sludge.
maby
Well-Known Member
I do believe that the extent of the problem has been significantly exaggerated in order to provide evidence to support the argument that we should continue to have access to red diesel.
ghostlymoron
Well-Known Member
I've never suffered from diesel bug as the last inboard engine I had was before the advent of bio diesel but a couple of things occur to me. All? bulk storage tanks (boats, filling stations, road tankers) are fitted with fresh air vents so there is always a route for atmospheric moisture to contaminate the fuel. Secondly, small portable fuel containers don't have a vent and are airtight so there's no way that moisture in them can contaminate the fuel.
Greenheart
Well-Known Member
Very interesting thread (considering I don't own a diesel).
I've got several gallons of ancient mixed 2-stroke fuel. No idea what to do with it.
Probably I should have offered it to the builders of a damp bonfire, pre-November 5th.
I heard that military tank engines run on diesel or petrol. Pity the MoD doesn't have a depot for cruddy mixed fuel which its Challenger engines will lap up.
I've got several gallons of ancient mixed 2-stroke fuel. No idea what to do with it.
Probably I should have offered it to the builders of a damp bonfire, pre-November 5th.
I heard that military tank engines run on diesel or petrol. Pity the MoD doesn't have a depot for cruddy mixed fuel which its Challenger engines will lap up.
dom
Well-Known Member
Allan
Well-Known Member
I've not read every post on this thread. During our two Atlantic crossings we carried 70 ltrs in plastic containers. We used the containers to top up the 140ltr tank. That way we could filter everything and check for contamination. There was always a little diesel in the containers after transferring the contents into the tank. I added enough Marine 16 or similar to treat a full container to the nearly empty vessel. I believe that should clean it ready for the next refill.
Allan
Allan
NormanS
Well-Known Member
I, probably like countless others, have never taken more than obvious precautions of reasonable cleanliness, and have never had any problems. It's not something that I worry about. Actually, I don't worry about many things, it doesn't seem to help. 
KellysEye
Well-Known Member
I found this for removing water from diesel: https://www.marship.eu/diesel-dipper
