Diesel Bug and Prevention Poll

What is your position/experience of the diesel bug and preventers?

  • I have never had the diesel bug and I DON'T use any treatment

    Votes: 41 23.4%
  • I have never had the diesel bug and I DO use a treatment

    Votes: 85 48.6%
  • I have had the diesel bug and at the time was NOT using a treatment

    Votes: 35 20.0%
  • I have had the diesel bug and WAS using a treatment

    Votes: 14 8.0%

  • Total voters
    175
  • Poll closed .
I am fairly convinced that the source of the fuel has a lot to do with it.
I'll second that. I have had two infestations, one in France (blocked the fuel pipe) and the other in the Algarve (bunged-up my Webasto). Both shortly after refuelling. On the second occasion I drained off a litre in a plastic bottle, it was cloudy. I tried adding a drop of biocide and the following day the fuel was clear with a drop of dark liquid in the bottom. Since then I have been using larger doses. Fingers crossed.
 
My new boat (to me) and diesel engine is starting well and I want to keep it that way.
This thread is of great interest as I do wonder whether buying additives is necessary.
Feedback here suggests that people are using it but the source of the fuel is just as important as adding stuff.

I read that it is a good idea to keep the tank topped up to avoid condensation. Makes sense.
The tank is about 3/4 full, but I have hesitated to bung in some fuel bought at the local petrol station as I read it has a higher bio diesel content, which in turn is more likely to absorb water. I will head over to the fuelling pontoon at some point, but should I avoid the diesel available at the forecourt?

Thanks
S

edit:

Just found this PBO test of treatments
http://www.marine16.co.uk/acatalog/diesel_bug_pbo_test1.pdf
 
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should I avoid the diesel available at the forecourt?

Thanks
S
In the rest of Europe they have to use white road diesel in boats. I don't know whether diesel bug is any more of an issue in Europe - possibly not.
But road diesel with FAME (biodiesel) added will as you say absorb water more readily than fame free red.
 
In the rest of Europe they have to use white road diesel in boats. I don't know whether diesel bug is any more of an issue in Europe - possibly not.
But road diesel with FAME (biodiesel) added will as you say absorb water more readily than fame free red.

Diesel with FAME added also has a very short shelf life. Luckily in the UK Red diesel for marine use if free of bio. However in Europe we have to put up with it.

In 2013, I had a new tank fitted. The old one had been used for 3 years in the Med and the bottom had a waxy black creosote like substance. In recovering the last of the fuel, some of this accidently went into the filter funnel (Racor water separator with fine copper gauze) and totally blocked it in seconds. I think we will see an increase in problems with this "sludge" which - being a wax and not a fine particle sludge, will, when stirred up by bad weather, block the filters instantaneously.

I think when leaving a boat at the end of the season it is now wise to make sure the tank is as empty as possible to avoid the drop out. It is also wise not to rely on just chemical treatments to ward of bugs, but to ensure that the conditions never exist for them to grow. I any case no chemical will solve the problem of the waxy bio deposit. Regular vaccuming of the bottom of the tanks can help.

It would be interesting to have some feed back from the commercial companies on this issue - as its not yet a major issue - but may well be in a few years.
 
Okay, so on the subject of treatment, both of these samples were taken from the same fuel, on the same day, and have had the same environment (granted one has had more water, I'm no scientist...)

One of these I put a few drops of Marine16 in.

Can you tell which one? :D

Resized%20BUG.jpg
 
In the rest of Europe they have to use white road diesel in boats. I don't know whether diesel bug is any more of an issue in Europe - possibly not.
But road diesel with FAME (biodiesel) added will as you say absorb water more readily than fame free red.

My boat has never been fuelled with anything but European road diesel (white) since 1997. I have usually left the tank full over winter but since understanding that the old 'condensation in airspace' myth is just that, for the past few years I have left it just as it finished up, anywhere between 1/4 and full. I have never had a real bug infestation but treated once with Startron when a filter was found with brown deposits.
 
Okay, so on the subject of treatment, both of these samples were taken from the same fuel, on the same day, and have had the same environment (granted one has had more water, I'm no scientist...)

One of these I put a few drops of Marine16 in.

Can you tell which one? :D

Resized%20BUG.jpg

April Fool - - oh Bu***** you posted that at 11.45 yesterday!
One looks like white diesel (left) and the other red. But one may be taken from the bottom of the tank where the red diesel staining seems greater. So tell us - why such a colour difference?
 
Not an Aprils Fools! Honestly ;)


I was thinking that last night, the anti bug solution must dissolve the red dye somehow? these samples were taken when I completely emptied my tank to remove any gunge on the bottom. I then pumped the fuel back in and through a water separating filter, and drained the water off plus a little bit of fuel. these samples were from the same drain off. Both samples were clear with no visual layers of bug in when taken, and were taken late January - so in 3 months its worrying to think what my tank would have been like if i hadn't put this stuff in!!
 
I use tiny amounts of fuel a year, usually less than 50 liters - never been a problem, but I do dose with Soltran and buy from a reliable source.

Oddly, I am thinking of moving to white diesel as it is easier to get hold of.
 
I'm doing absolutely everything wrong! Avocet has a 9 gallon mild steel (galvanised) fuel tank that was criticised by the surveyor when we bought the boat (over 20 years ago). The fuel take-off is from a sump at the lowest point of the tank. I have a single (car-type) spin-on fuel filter with a drain cock. I've only ever used white road diesel, I use very little each year (5 gallons maybe) and I don't brim it for the winter. I use no fuel treatment.

Every time I've drawn off some fuel from the drain cock on the filter, it has been clear and had no water in it. A couple of times when I've changed the filter, I've cut the old one open and found nothing that answers the description of diesel bug that has been mentioned in this thread. I can't see inside the tank (which is over 40 years old, I'm pretty certain). Why on earth don't I have a problem?!
 
Probably because you are using white which at the normal pumps is fast moving - that the tanks there don't sit idle for ages and has very little water ingress? Also i would put money on that the white diesel has its own treatment in.. think of red diesel designed for tractors, sitting in a barge in a moist environment at the coast, which is probably an old 50's tanker that has never been cleaned.. and only refuels once a month if that? I have also heard that red is a different quality than white. they had a lot of problems in agriculture with the introduction of common rail engines running of the stuff. A friend of a friend ran his audi a3 of red diesel and in a year went through 3 injectors. please note I do not condone doing this!!!

otherwise your very lucky Id say! :)
 
Hmm. I hate to think what the bottom of some filling station tanks are like. Out of sight, out of mind.
I get my fuel from the company that supplies many big ferries, and has a throughput of millions of litres.
 
Probably because you are using white which at the normal pumps is fast moving - that the tanks there don't sit idle for ages and has very little water ingress? Also i would put money on that the white diesel has its own treatment in.. think of red diesel designed for tractors, sitting in a barge in a moist environment at the coast, which is probably an old 50's tanker that has never been cleaned.. and only refuels once a month if that? I have also heard that red is a different quality than white. they had a lot of problems in agriculture with the introduction of common rail engines running of the stuff. A friend of a friend ran his audi a3 of red diesel and in a year went through 3 injectors. please note I do not condone doing this!!!

otherwise your very lucky Id say! :)

Well, I thought it would be due to using "road" diesel, but then there were several posts about this having biodiesel in it - which is apparently more susceptible, so that started me thinking! One of these days, I'll have to borrow an endoscope and see if I can have a squint in the tank.
 
Hmm. I hate to think what the bottom of some filling station tanks are like. Out of sight, out of mind.
I get my fuel from the company that supplies many big ferries, and has a throughput of millions of litres.

To be fair, I accidentally put a tank of petrol in my range rover but knew what i had done before touching the key so managed to save it all. pumped the tanks out back at the workshop and was surprised how clean the bottoms were! probably because the diesel is always moving helps so the filters catch it..

Saved the Rangie, cant say the same about my dignity... :D


Well all fuels will soon have bio in i bet... best get treated, think thats the easiest solution for a bit.!
 
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