Condensation / diesel bug over winter

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Leisure 27

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Is it a good idea to keep your tank full in winter to protect against condensation. What should I add, Diesel Bug, Diesel Bug Complete, Startron Diesel additive or another. As diesel got a shelf life.
 
I use Marine 16 Complete now that I have got rid of my traces of bug and it's kept me 100% free for the last two years.

I don't leave my tanks full as I don't accept the condensation theory but some forumites do believe it and you will never resolve that dichotomy.

Diesel will last for several years without any serious deterioration and for probably for decades if sealed in airtight cans but, once again, not all forumites will accept that either. :)

Richard
 
jetgo888 said:
Is it a good idea to keep your tank full in winter to protect against condensation. What should I add, Diesel Bug, Diesel Bug Complete, Startron Diesel additive or another. As diesel got a shelf life.
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There has been postings here in the past from people trying to reproduce condensation in boat tanks without success. I did some rough calculations recently for a 1000lire diesel tank half full to see how much moisture could possibly be extracted from the fuel and from the air above that moves in and out of the breather with temperature change and i came up with the figure of 3 to 5 teaspoons full of water in a year. I have never kept my diesel tanks full in the last 30 years and never used an additive and always refuel from where they have a quick turnover of fuel. I believe most of the water that gets into boat tanks is from leaky filler cap seals.

Www.solocoastalsailing.co.uk
 
Plum said:
There has been postings here in the past from people trying to reproduce condensation in boat tanks without success. I did some rough calculations recently for a 1000lire diesel tank half full to see how much moisture could possibly be extracted from the fuel and from the air above that moves in and out of the breather with temperature change and i came up with the figure of 3 to 5 teaspoons full of water in a year.
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Agreed. And stuff-all of that will be in the winter because the diurnal temperature variation is less and anyway cold air holds less water.

I used Startron diesel additive until the bottle ran out and now use Fuel Set, because that's what the place where I ran out of Startron sold. Never had any problems. I dose at about 5x the recommended rate.
 
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If cold air holds less water why is it my boat gets piss wet through inside in winter and I need a humidifier and still get black dots on stuff yet is not too bad in summer
. I am a livaboard but cook with the hatch open Thank god for Meaco
 
I'm fairly firmly of the opinion that any issue over the winter is fairly marginal. The airflow is so marginal and the amount held so lowthat there are plenty of other ways to muck up your fuel. On our first boat the exhaust and fuel filler rubbed holes in each other in a hidden place and we got water in the fuel that way. Now on the list to check with any new boat I look at!
 
If it makes you feel better, fill the tank before winter. It won't make any real difference. But it is worth always using a decent anti-bug treatment, such as Marine 16.
 
JBJag27 said:
PBO got a scientist type to compare them, although he apparently has no beard he seemed quite thorough.
http://www.pbo.co.uk/gear/12-diesel-bug-treatments-tested-43353
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Excellent, thank you. I bet some will say its all wrong though in the true spirit of the forum! ;)

I reckon that the world of boats is easily divided into those that have had the problem and those that havent. Im in the first group and we will do everything in our power to prevent it coming back! Good luck to th doubters and I hope you never have one of the worst boat jobs thrust upon you, especially if you are becalmed off St Lucia........
 
I only have an interior filler.

Just taken 1 litre of water and about 4 more of dirty fuel from the drain on the bottom of the tank.

Whether dirty fuel or condensation or both?
 
sjdtuk said:
I only have an interior filler.

Just taken 1 litre of water and about 4 more of dirty fuel from the drain on the bottom of the tank.

Whether dirty fuel or condensation or both?
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Unless you have the QE II as your yacht, I'd say you have about 200 x as much water in your tank as could have come from anything other than a gross leak or abysmal fuel. Get rid of that water as soon as you can, and find the leak (or change supplier) and fix it!

Even the PBO article - of no scientific merit whatsoever - admits that without free water there'll be no 'bug'. Free water is not inevitable: I've never found free water in my tanks, and I keep the tank empty all winter. I do check in the spring via the inspection hatch.
 
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