Diesel bug - anyone with experience?

We were lucky it hadn't happened on entry to the harbour the day before.

That's my fear. I recall dropping sails outside Calais on a lee shore once; engine failure then would have been a disaster. Although I winced about the cost of a polishing set-up, when you think of the cost of a new bit of electrickery (not that I, the original luddite would buy anything), it's not that expensive.
 
I thought as a new member (who joined because i hope to be living in Sardinia soon and buying a sailing boat as a possible live aboard when her indoors drives me crazy) i might write about what i have witnessed af diesel bug in the last few weeks.
I built a "diesel bug removal" website (Google it) for a friend who had just purchased the fuel polishing machinery to supplement his retirement income while living aboard his narrowboat in a Gloucestershire Marina. Cost of about £2000 and nearly paid for itself already in the number of fuel tanks he has cleaned.
But heres the insightful stuff:

Most remarkable job i've witnessed - 15 gallons of water extracted after an engine stoppage in the marina, having just arrived and moored up from coming down the River Severn. The polishing machine started sucking air because all the fuel has been burned in the engine and only water was left.

An assortment of debris including leaves, plastic bits, rust flakes and the slimey diesel bug trapped in the glass filter bowls for the owners to see.

Gloucester pilots recommending fuel polishing before exiting Sharpness lock for the trip to Portishead and onward to Bristol, after towing back a breakdown mid channel. My friend had to polish his fuel before having another go.

Some fuel tanks were spotless, but these seemed to belong to regular users.

Advice and stories gleaned from engineers and fuel additive suppliers met along the way.....

1.Keep the fuel tank filled up to reduce the air pocket and subsequent condensation
2. Be careful who's diesel you buy. Diesel bug can be imported onboard at each fill up.
3. New bio fuels have lower sulphur content and hold more water (which the microbial diesel bugs feed and reproduce on)
4. Fuel blenders alter the level of bio diesel to reduce the costs for some of the bigger suppliers who compete on price at the fuel pumps. So cheapest per litre might mean "riskiest per litre"
5. Bio diesel breaks down after about 6 months.
6. The problem is getting worse as the levels of bio diesels increase and sulphur content reduces.
7. Some heavy haulage lorries are breaking down because their injectors can't handle the new bio fuels.
8. There are night shift workers individually polishing the fuel in public transport buses and coaches to minimise breakdown on the high ways.
9. After a regular fuel polishing (which, by the way, returns all the polished diesel back into the tanl, so no fuel loss) use an additive to kill any new infections.
10. Marine 16 is talked about as being the best additive out of all of the additives available.

So there you have it.

Only a couple of months, about a dozen boat tanks cleaned, and all this comes to the surface simply by following my friend around as he polishes boat and agricultural fuel tanks to make ends meet. We wonder what 12 months will show.
 
Just had new diesel installed to replace 2 stroke petrol engine.

I'm starting off with Aquasolve in the tank which is supposed to completely emulsify any water in the tank allowing the engine to "burn" it with the diesel. This should also prevent the formation of the water/diesel boundary layer in which the diesel bug thrives.

Anyone else had experience of Aquasolve to back up their claims?

Details here: http://www.covalaquasolve.co.uk/
 
An interesting thread, luckily I have a sump in the base of the fuel tank which I drain off about half a pint of diesel two or three times a year. I always fill up with red from ether Bradwell or the little garage at Bicknacer which is high sulphur with no bio(I did ask), never with Tesco's finest or any road fuel. I have never had diesel bug and never dosed the tank, my only concern is water in the tank which I get a minimal amount when I drain off but it is only a tea spoonful each time.
 
Last year one of our club cruises was delayed because one boats engine wouldn't start. RCR came out, eventually, took a few bits apart, diagnosed diesel bug, poured in some Marine 16, and the boat started and came on the trip.

I think Marine 16 would be my first port of call.
 
We hD a chap polishing fuel tanks round the oth day.
He said the bug needs water to live.. It gets there either from condensation or dirty fuel..

Clean tanks and no water seems to be the answer.

PS am changing the tank inspection hatches so I can get in easy.. It only takes one fill of dirty fuel from a suspect fuel barge and ynhave a problem again.
 
We've got a totally inaccessible tank with no access except the small filler hole. At the start of the the season and again before our last trip (Chatham B'sea and return) I sucked out a gallon of fuel from the bottom of the tank, there was no free water but a few clumps of red muck and other crud and it was slightly cloudy. Short of taking out the engine or cutting out the cockpit floor this is about the best I can do. We do only use red diesel and try to keep the tank as full as possible.
At the start of the season I changed the filter for the first time since getting the boat in mid-2011 and it looked like new.
Do the panel think it's worth adding a de-bug treatment or should I leave "well" alone?
 
We've got a totally inaccessible tank with no access except the small filler hole. At the start of the the season and again before our last trip (Chatham B'sea and return) I sucked out a gallon of fuel from the bottom of the tank, there was no free water but a few clumps of red muck and other crud and it was slightly cloudy. Short of taking out the engine or cutting out the cockpit floor this is about the best I can do. We do only use red diesel and try to keep the tank as full as possible.
At the start of the season I changed the filter for the first time since getting the boat in mid-2011 and it looked like new.
Do the panel think it's worth adding a de-bug treatment or should I leave "well" alone?

If you can find a mobile fuel poloishing service locally it would be worth seeing if the access hole is big enough for them to get their lances in.
The two lances that go into the tank are stainless steel with a diameter of about 8mm each and go through the filler hole.
The red muck doesn't sound like diesel bug to me but whatever it is i'm not sure a diesel bug treatment will remove it. Sounds like polishing is the answer, but an additive put in first and left overnight should kill any microbial presence and it will sink to the bottom awaiting the arrival of your fuel polisher and his machine.
Heres a youtube demo showing "through the hole access":
https://www.youtube.com/watch?v=V1eFtQDN9q4
 
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