the perils of white diesel and the bug

[Fox Morgan]

I just finished writing up a quick blog about how I recently had to sort out a tank full of diesel buggy fuel.

The symptoms only became apparent after a rough Irish Sea crossing in June. We (a friend and I) put it down to an air lock.
Then as the engine cut out again, several hours of motoring and days later, we put it down to water still making its way out.
When it cut out again, I suspected something else.
When it cut out again, I went through the entire fuel system and discovered that in the space of 10 days, my entire fuel tank had turned to opaque pineapple juice.

I've only ever used white diesel, given that I only use about half a tank of fuel a year, the cost is negligible.
I now realise that it's equally, if not more prone to the bug as red diesel. Marine 16 is now my friend.

You can see what it looked like via my blog post and the steps I took to sort it out.
includes a free "diesel" joke

http://www.boogie-nights.org/2016/08/diesel-fitter.html

 

[[70521]]

Love the engine nappy.

 

[capnsensible]

Its only the UK that has red. The rest of the world is normal. I goy diesel bug in Cape Verdes. Sorted in St. Lucia, a very nice tropical climate for cleaning a flippin diesel flippin tank..........:ambivalence:

 

[TallBuoy]

it could be that white diesel bought from a road garage contains up to 7% bio-fuel. Red Marine diesel sold, at least on the south coast of UK, contains no bio content for the very reason you have experienced.

 

[Fox Morgan]

it could be that white diesel bought from a road garage contains up to 7% bio-fuel. Red Marine diesel sold, at least on the south coast of UK, contains no bio content for the very reason you have experienced.

yes, that's what I have discovered. But never paid attention to the fact that diesel from Tesco etc contains bio. I just fill up a small jerry can when i fill up my van with diesel. I then decant that jerry can to my boat. I do this from time to time to keep the boat fuel tank topped up. I haven't filled up at a marina since I was in a french marina over two years ago.

 

[NormanB]

Cladisporium resinae does not mind what colour dye is in the fuel, it feeds off bacteria in the fuel water interface.

 

[Fox Morgan]

Cladisporium resinae does not mind what colour dye is in the fuel, it feeds off bacteria in the fuel water interface.

there was no water in my tank. The professional fuel polishing chap was very surprised to see that there was none in the tank.
What I had was a bacterial bloom, that was activated by the warm weather. The bacteria was living in the bio part of the fuel. Hence the entire fuel tank changed colour in a matter of days.

 

[lw395]

there was no water in my tank. The professional fuel polishing chap was very surprised to see that there was none in the tank.
What I had was a bacterial bloom, that was activated by the warm weather. The bacteria was living in the bio part of the fuel. Hence the entire fuel tank changed colour in a matter of days.

That cloudy mess looks like some sort of emulsified diesel?
There will be water in that.
The bacteria produce water by respiration.

 

[Fox Morgan]

That cloudy mess looks like some sort of emulsified diesel?
There will be water in that.
The bacteria produce water by respiration.

yes, I took a few small bottle samples straight from the fuel feed from the bottom of the tank and left them to stand. I only managed to extract water (tiny amount) out of the diesel after adding the biocide. Otherwise, the diesel just stood for days and remained cloudy.
Although my sample bottle with the added marine 16 was the one that turned to a urine colour and water along with white slime settled on the bottom of the bottle. I don't know if the rough trip to Ireland allowed a small amount of water into the tank which then emulsified and it grew from there, or, if I had the bug developing during winter/spring and only when I hit some properly rough weather that it finally mixed it up.
The chap who came to clean it, said it was becoming more common, this kind of diesel bug which isn't necessarily caused by water entering the tank or by condensation but is a result of short shelf life of pump diesel.

 

[matt1]

yes, I took a few small bottle samples straight from the fuel feed from the bottom of the tank and left them to stand. I only managed to extract water (tiny amount) out of the diesel after adding the biocide. Otherwise, the diesel just stood for days and remained cloudy.
Although my sample bottle with the added marine 16 was the one that turned to a urine colour and water along with white slime settled on the bottom of the bottle. I don't know if the rough trip to Ireland allowed a small amount of water into the tank which then emulsified and it grew from there, or, if I had the bug developing during winter/spring and only when I hit some properly rough weather that it finally mixed it up.
The chap who came to clean it, said it was becoming more common, this kind of diesel bug which isn't necessarily caused by water entering the tank or by condensation but is a result of short shelf life of pump diesel.

Interesting that you say it's becoming more common. Never had a problem in last 40 years and then without warning I have had a similar experience to you. eg following a spell of warm weather and a bit of motoring in roughish seas. I took a different approach to dealing with it; removed tank, cleaned it all out, replaced the fuel lines and started again with new diesel (and Marine 16, which I will use religiously every top up).

Took me two days to resolve and still cost me the best part of £300 even though my labour was free

BTW mine was mostly pink diesel, with a slight dilution of the odd 5 litre road diesel top up

 

[Fox Morgan]

Interesting that you say it's becoming more common. Never had a problem in last 40 years and then without warning I have had a similar experience to you. eg following a spell of warm weather and a bit of motoring in roughish seas. I took a different approach to dealing with it; removed tank, cleaned it all out, replaced the fuel lines and started again with new diesel (and Marine 16, which I will use religiously every top up).

Took me two days to resolve and still cost me the best part of £300 even though my labour was free

BTW mine was mostly pink diesel, with a slight dilution of the odd 5 litre road diesel top up

costs for my fix was : 2 bottles of marine 16 at £9 per bottle.
A crazy ride in my dinghy across Poole harbour: priceless
moorings for an evening in Poole: £41
diesel polishing : £130
plus a bottle of Rum to thank a mate for helping to get the engine going twice.

 

[LittleSister]

there was no water in my tank.

As I understand it diesel has a degree of moisture in it as a matter of course. I suspect that whether or not you have water visibly seperated out at the bottom of the tank, there is enough moisture for some bug to be getting on with.

I don't know, of course, but would guess you may well have had a gradual accumulation of bug debris in the bottom of the tank over a prolonged period of time, and the rough crossing has stirred it up into the fuel at whihc point it becomes a problem.

 

[vyv_cox]

Difficult to blame warm weather I think. Our boat is in Greece where temperatures almost always exceed UK 'warm weather'. There are cases of diesel bug here of course but relatively rare due to the common fuelling method by mini-tankers, whose turnover is relatively high. Word has it that the bio content of Greek fuel can be up to the permitted maximum.

 

[[70521]]

After talking to a number of plant engineers who run big diesel units I switched from Red to White, but a "good quality" white. I only use about a tank full a year and it is easier for me to fill a jerry can up on the way to the boat, go sailing, fill the tank and pop any unused fuel in the car when I return ashore.

Like Baldric I have a cunning plan to empty and steam clean the tank every three years.

 

[dom]

Couple of random points from a friend in the oil business:

1. The red/white debate is essentially a red herring. The dye pertains solely to the duty status of the fuel and has an uncertain (next point) influence on its composition. 'Nominal diesel' may contain a significant spectrum of distillates and other bio ingredients.

2. Road white diesel in the EU must contain at least 7% bio, (FAME) which works fine in cars, but its highly hygroscopic nature renders it entirely unsuitable for the marine environment ....even if the diesel has no free-water contamination at the time of fueling.​

For this reason FAME Free diesel (permissible under EU Law for marine use) with a suitable biocide premixed additive is the way to go and many/most of the south Coast marinas will sell this stuff (usually from Esso refinery in Southampton). The premixed bit is relevant in that it helps ensure that the suppliers' tanks are also bug-free, but one also needs to ensure that the diesel is free from free-water, and that the tanks are well turned over and properly maintained.

Recent post on this here: http://forums.ybw.com/forums/showthread.php?462596-Are-Diesels-really-viable-in-boats-nowadays/page3

 

[lw395]

....

Like Baldric I have a cunning plan to empty and steam clean the tank every three years.

Personally I think it's better to get the tank 'reasonably clean' every year than 'spotless' every three years.
The idea is to never have more crud and water than your filters can easily cope with.

 

[dom]

Personally I think it's better to get the tank 'reasonably clean' every year than 'spotless' every three years.
The idea is to never have more crud and water than your filters can easily cope with.

Fair enough in theory, but in practice leaves one managing an unstable dynamic equilibrium where the bugs could make significant gains before being discovered.

Perhaps Yachting Monthly should seek the advice of a professional oil-man as to whether perma-clean bug free diesel tanks are an achievable goal for most yachts?

 

[RichardS]

Perhaps Yachting Monthly should seek the advice of a professional oil-man as to whether perma-clean bug free diesel tanks are an achievable goal for most yachts?

My experience is that provided you dose the fuel with biocide at every fill up then bug-free tanks are not difficult to achieve. There will still be some dirt in there from the suppliers tanks and from the atmosphere but that kind of dirt doesn't multiply so it's not a problem.

Richard

 

[dom]

My experience is that provided you dose the fuel with biocide at every fill up then bug-free tanks are not difficult to achieve. There will still be some dirt in there from the suppliers tanks and from the atmosphere but that kind of dirt doesn't multiply so it's not a problem.

Richard

To be honest that's my experience too: I tend to stick to the FAME Free pre-dosed stuff and have never seen anything cruddy in the pipette sample I occasionally draw from the bottom.

 

[GrahamM376]

Road white diesel in the EU must contain at least 7% bio, (FAME) which works fine in cars, but its highly hygroscopic nature renders it entirely unsuitable for the marine environment ....even if the diesel has no free-water contamination at the time of fueling.

We've been using white exclusively for 10+ years and intermittently before that. In common with hundreds of thousands of European boaters, we have no problems with it and instances of bug we hear about are rare, compared to UK. I suspect longer marina storage times due to low turnover in the UK may be part of the problem along with greater temperature variations in above ground storage tanks.