NormanS
Well-Known Member
It's good that you folk from far away, know so much more than me, about what happens where I am. ? Happy Christmas.
Winterising diesel fuel tank
- Thread starter FairweatherDave
- Start date
LONG_KEELER
Well-Known Member
Can we fix a date so you can start my lawn mower sometime in March ?
Refueler
Well-Known Member
You believe that Diesel is different for you ??
The only usual difference - is the grade for winter use. Where the seasonal temperature determines the level of CFPP / Cloud Point temperature quality of the fuel.
All other parameters unless Arctic / Antarctic use remain same grade by grade.
roaringgirl
Well-Known Member
Can we fix a date so you can start my lawn mower sometime in March ?
When I changed the engine in my car, I put in a lump which hadn't turned over for 3 years. The fuel in the tank had been sitting for 2 years. It started on the 2nd try!
LONG_KEELER
Well-Known Member
Things like that were the norm for me like Seagull outboards and mowers until ethanol was added to petrol. You can still find ethanol free petrol in the UK. The top grade of Esso petrol although it may say E5 on the pump is ok but there are a few areas , for logistical reasons that can't stock it. I only purchase this grade now although when off cruising you have to take what's available.
Refueler
Well-Known Member
You do realise that fuel is produced in only a limited number of refinerys, plus shipped in from abroad. It is then stored in large tanks containing thousands of tones waiting for distribution.
No terminal or refinery could afford to produce a 'special' one-off for a location as where is it going to be stored prior trucking out ? I am not saying its not do0ne ... we have that **** Aspen as example - but costs ??
E5 is 0 - 5% by EU and now UK rules .... Various producers kept Super Prem at near 0% .... but no longer g'teed.
LONG_KEELER
Well-Known Member
Refueler
Well-Known Member
Which re-iterates what I said .... 0 - 5% ......
Problem with websites as well - they do not always keep pace with the changes ....
LittleSister
Well-Known Member
Several posts give examples of problems with aged petrol. The bio additive in petrol is not at all the same thing as that in diesel, so is no guide to what the result will be for the OP or anyone else with old diesel.
If people are anxious about the potential for condensed water in their diesel from a part filled tank (unnecessarily, in my view) why not connect the breather at its opposite end to the tank to a long extension tube of e.g. cheap plastic tubing, and leave it trailing downward from the upper breather position well above the tank.
The air already in the tank probably contains less water than an equivalent volume of 'fresh' diesel.
The air drawn into the tank as temperatures rise and fall (which I'm anyway not convinced will be either (a) significant in volume or (b) significantly different in volume than if the tank were filled with diesel!) will be the same air in the top of the breather and extension pipe each time, and any 'new' air drawn into the lower end will anyway never reach the tank and also have the opportunity for its moisture to be condensed out when conditions suit and drain way down the tube away from the tank.
But then what you worry about instead? ?
If people are anxious about the potential for condensed water in their diesel from a part filled tank (unnecessarily, in my view) why not connect the breather at its opposite end to the tank to a long extension tube of e.g. cheap plastic tubing, and leave it trailing downward from the upper breather position well above the tank.
The air already in the tank probably contains less water than an equivalent volume of 'fresh' diesel.
The air drawn into the tank as temperatures rise and fall (which I'm anyway not convinced will be either (a) significant in volume or (b) significantly different in volume than if the tank were filled with diesel!) will be the same air in the top of the breather and extension pipe each time, and any 'new' air drawn into the lower end will anyway never reach the tank and also have the opportunity for its moisture to be condensed out when conditions suit and drain way down the tube away from the tank.
But then what you worry about instead? ?
NormanS
Well-Known Member
A proper fuel tank has provision for drainage from the bottom, and saves all that bother.
Plum
Well-Known Member
Agree. I did some worst case calculations on how much water could collect in the bottom of a half full tank of diesel over a 6 month winter (other than from a leaky filler cap) and, just as you suggest, the answer was close to a desertspoonfull. I have never taken any specific action to alter my fuel level in the winter and have never suffered from water in the tank.
Www.solocoastalsailing.co.uk
LONG_KEELER
Well-Known Member
It would be interesting to know if the occurrence of the diesel bug has increased in line with the introduction of ethanol in diesel. About 20 year's ago I had the diesel bug and had the tank steam cleaned along with cleaned fuel lines. After that, I only used white diesel with ethanol and suffered no further problems.
Part of the problem appears to be water in fuel tanks due to condensation when the tanks heat up during the day, and cool down at night, although I have never saw a water layer in the filter. Perhaps , even if you fill the tank to the brim , water can still be held in the ethanol.
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RunAgroundHard
Well-Known Member
Free water in the tank would be at the bottom of the tank, with diesel on top. Assuming most diesel take off points are off the bottom, then this free water would not get into the filters. Any water absorbed by ethanol, fits between the molecular spaces of ethanol and then gets burned in the engine rather than filtered. All water in the filters is from free water in the fuel.
Refueler
Well-Known Member
When Ethanol is blended into Diesel .... usually only in ULSD .... it also has an Emulsifier added to prevent any moisture related problems .......
LONG_KEELER
Well-Known Member
Thanks. That's good to know.
Freebee
Well-Known Member
diesel always has a dissolved water content.............. as it becomes warmer so it can dissolve more water into itself this is called water solubility. when considering the effect of condensation in a tank , we should also consider the solubility effect and the changes that occur as fuels cools causing a release of free water
Refueler
Well-Known Member
All fuels have a moisture content .... along with suspended water.
We go to great lengths to quantify and reduce to industry accepted levels - not only for Fuel Quality and 'Burn' but also it incurs penalty on sale price ....
Rarely today - but was many years ago - terminal storage tanks could have a water layer by design with the fuel sitting on top ... luckily as I say - this is rare today ... but water is often found in tank bottoms due to settling out.
Freebee
Well-Known Member
water layer by design reminds me - some older RN warships from 60's and 70's had water compensated fuel tanks -that is -as the fuel was used up so sea water was added to the fuel tanks to keep the ship in trim .They used large centrifuges and filter water separators about as big as a Ford Transit (other brands are available) to remove the water before the fuel was burnt in the gas turbines .
Plum
Well-Known Member
Good point and I included that factor in my calculations I referred to in post #51
Www.solocoastalsailing.co.uk
Momac
Well-Known Member
So for a boat left over winter and unused that water which might be released in frosty weather would be reabsorbed as the weather warms in spring?
