Diesel tank sediment -advice

[davidphillips]

I've just removed (for other reasons) my diesel tank which was new 5 years ago and find that there is a fair amount of black sediment at the bottom. No problems with the engine/filters and the diesel that came out of the tank was clear except the last litre or two. I've used biocides fairly regularly. Anyone know if this is this likely to be diesel bug?

 

[chrisc]

sounds like a growth ,if you use ,the same biocide too regularly you will get bio growth that is immune. Have you any water in diesel ? most growth is only on the interface between water and diesel.

 

[BlueChip]

These are dead bugs that the biocide has killed. Soltron which contains an enzyme is supposed to digest those sediments. I will let you know in a month or two - I have the same trouble and have just double dosed with Soltron

 

[davidphillips]

There was no water in the tank or the primary filter.

 

[colvic]

Hi

Had to clean out our fuel tank several years ago when the filter became blocked with black sediment which sounds like your description. As you say, virtually all the diedel was clear except the last few litres. Scooped most of it out, cleaned the tank, which was still in situ as impossible to remove without removing the engine, and always used diesel from fuel stations after that; never had any more trouble and after almost five years the initial filter in the system had just a VERY small amount of sediment in it.

Try getting some diesel from your usual supplier in a plastic jerry can and leave it to stand for a while...you could be surprised at just how much CRUD there will be in it.

Phil

 

[cliff]

[ QUOTE ]
I've just removed (for other reasons) my diesel tank which was new 5 years ago and find that there is a fair amount of black sediment at the bottom. No problems with the engine/filters and the diesel that came out of the tank was clear except the last litre or two. I've used biocides fairly regularly. Anyone know if this is this likely to be diesel bug?

[/ QUOTE ]Sounds like it could be dead bugs or even general crud settling out of the diesel. While you have the tank out consider having a sump fitted to the bottom of the tank and a drain point at the bottom of the sump. A sump capacity of 3 to 4 pints is enough and it is so easy them to drain a couple of cupfuls out every now and again (until clean diesel is coming out the drain) and getting rid of all the crud , water and dead bugs. Why folk rely on "snake oils" to keep their diesel tanks clean is beyond me, I much prefer to physically remove the offending material from the tank.
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“Artificial intelligence is no match for natural stupidity”
Skype id:cliffillupo

 

[Guest]

Biocide and crud ...

Generally diesel does carry sediments despite quality controls, but normally they would appear as light colour and literally takes many years to accumulate. The darkest you would expect in normal seds would be like terra cota clay colour - but this is rare. The amounts are minisule and need very fine lab filters to extract .... average we use would be less than 0.8 micron ....

Now onto black seds .... often this is dead bugs killed by 'old-age' - yes it happens !! or by biocide. Over judiciuous use of biocide is not generally advised - despite the lable on the can - they want to sell the stuff !!
A lot of bugs will actully pass through the system - as its so fine - but established and grown bugs will start to clog things up. If you treat every litre - you will actually create a situation of accumulation of crud that will eventually do similar to the live sods...... block your filters. Biocide originally was designed to cure a problem and then you suck it al out / clean tank and go away happy. Unfortunately a system has evolved where people consider biocide as a prevention .... not true. It is medicine after the fact.

Soltron by all accounts is different in that it breaks down the crud to be burnt off with the fuel .... in fact sorry Soltron - but there are other additives out there that do it - I have an additive division of my lab that uses tons every month of variuous fuel additives in the industry ....

Best thing ..... empty it all out, get a friendly steam cleaner guy to steam the tank .... let the heat dry it and then refit. Refill and only use biocide or soltron at intervals - not continuously - that is my opinion .... if you do have a bad batch and it all goes wrong - then I'm sorry but it is not usual to happen so quick.

A good practice is to drain off a tank 1 or 2 x a year and suck out any crud .... if you cannot drain from a sump.

Me ? I haven't used bio in my tank for years .... in fact on present boat I haven't used it at all .... my tank remains part filled every winter, stands for months on end, never gets drained or cleaned...... yes - I really do not take my own advise !! But that is my problem and does not change the fact of what I advise.

Onto supply .... what makes you or anyone else think that a smart exterior tank in swank marina or supply location is any better than a rusty exterior tank in a yard etc. ? The number of swank tanks that I have inspected that are infeste so badly that it has had to deducted from tank volume to get transfers correct - I have lost count.... (now I'm talking about 10,000 - 30,000 ton export tankage). Remember that fuel is blended / mixed into many others fuel .... you have no idea where your fuel comes from and ALL diesel is affected anyway .... NO fuel company puts additive in to control this unless absolutely necessary.

Final comment - sensible husbandry does more good than a bucketful of chemical .... but I'm sure there are plenty out there who would gladly sell it to you.

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