Winterising diesel additive or not?

Meagain

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Lay up time is here and next week we are bringing her ashore. It’s our first time with diesel power so I understand it’s best to brim the fuel tanks but keen to hear views on whether to add diesel additive or not. if yes which is best ?
Many thanks
 
Yes to adding an additive to suppress the diesel bug proliferation.
Bit like washing powder ......take your pick and follow instructions re dosage.
15 years using Startron seems to have prevented it for me .Although I may add I use it as a maintenance dose throughout the summer and stronger for the winter lay up .
Having said that this year I have changed brands to something else .
We have clear “ glass “ bowls on the racors so I can see or I think I will be able see any black crud .Thus far nothing .
Being Med based I don’t top up .I would in the UK though to minimise the condensation surface area from the damp air .
Again clear glass bowls .....supposed to be drained off but I never drained anything other than fuel .

There are two anti bug approaches.
One a type of anti biotic ..... so kills it and stops it breading forming the sludge .
Second a chemical that dissolves any water into the fuel in a format that’s burnt off undetected by the injectors.

The bug thrives on the water fuel interface and it’s by products and dead micro organisms then sink to the bottom and form the injector killer sludge .

Startron works on dissolving the water , removing the interface .

That’s probably why I have never seen any water ?
 
Lay up time is here and next week we are bringing her ashore. It’s our first time with diesel power so I understand it’s best to brim the fuel tanks but keen to hear views on whether to add diesel additive or not. if yes which is best ?
Many thanks

it's a tricky choice- best thing for boats of either petrol or diesel is to use them. leave them over the winter and some condensation will form regardless. ends up as water in the bottom of the tank - burn that diesel over the spring/summer on a regular basis and refill a few times, then any water that accumulates over the winter will mix into the diesel and go through the engine no problem.
however if you only use small amounts of diesel each year, watch your fuel separators for signs of water and use a diesel bug additive as that winter condensation will slowly accumulate over the years and become a problem - especially in a hot med climate.

as to which bug medicine is the best - that depends on what bacteria/fungus you are infected with. Soltron/Marine 16/Fuel set - take your pick as a winter additive. (I use fuel set- seems to work)

personally in the UK I never bothered brimming the tanks in the autumn, better to run it low, refill it partially in the spring and use it rather than let anything accumulate. Bio diesel is a problem these days as well, keep your fuel moving/changing else it stratifies. In the med watch closely for any signs of diesel bug and treat accordingly, the warm weather makes it grow fast.
 
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We always brim the tanks for winter lay-up to reduce condensation in the tanks (according to received wisdom) and use an additive all year round. Fuel Doctor was the potion of choice on the last boat, which seemed to work okay and now switched to Marine 16 on the current boat - used by the RNLI for what it’s worth.

Soltron was the much vaunted elixir hereabouts in the days of hlb (RIP) - he and DepSol used to sell it iirc but never tried it myself.
 
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Never bothered with magic potions or fuel levels. Just used the boat. Seems to have worked for last 5 decades or so.
Only problems came with contaminated fuel, taken on from reputable marinas,once water in petrol and then bug from diesel,curiously foamy waxy muck blocking filters.
Managed to limp home on both occasions.
 
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I've used Marine 16 bug killer for the past 2 winters and will be doing so again this year. Also worth cleaning the threads on your filler cap and giving it a good smear with vaseline to keep the water out. Check O ring condition too.
 
Never bothered with magic potions

A lot of people dont. And they may never have a problem.

Similarly it is not possible to prove whether he use of a treatment has had any benefit.
Many fuel treatments claim to keep the fuel system clean as well as helping protect against bug.

I need to order some fresh treatment. The last lot cost under £30 . I may have missed a couple of top ups but it has lasted well over a year. So it's not particularly expensive.
 
Many thanks all for your comments and help, have gone with brimming the tank and added 50ml Marine 16 (800 litre tank)
 
I have used a biocide for 5 years now at preventative dose level, for the last 15 years Grotamar, unfortunately now only available to professionals.

As said above diesel bug grows on the interface between diesel and water at the bottom of the tank, Luckily I have sumps in my tanks and each season we strip them out and inspect carefully fuel and water drawn out and prefilters.

When I bought current boat at 7 years old it had fuel bug through lack of use.

Personal preference is a biocide I dont want disolved water near my fuel injection system.

Fuel bug bi product ( sh1t) is corrosive and is obviously a problem for engines and fuel injection system.

The main corrosion risk however is to aluminium fuel tanks where it corrodes through them, we are seeing fuel tanks as young as 7 years old where untreated fuel bug and water has eaten through the tank. Also fuel tanks can corrode through from the outside if sat in salt spray.

Fuel bug is much more of a problem now than it used to be as with ULSD diesel there is barely any sulphur in it which kills algae and funghi .
 
Lay up time is here and next week we are bringing her ashore. It’s our first time with diesel power so I understand it’s best to brim the fuel tanks but keen to hear views on whether to add diesel additive or not. if yes which is best ?
Many thanks

I’ve never bothered with chemicals but I don’t lay the boat up. I use it all year round.

Last year I had 6 months off the boat (having suffered a spider bite - another bug story) and the bug I’ve suffered in the diesel since has been an ongoing nightmare.

When I thought I got to the bottom of it, last Saturday I lost an engine again, single handed blowing f5-6. Airlock, cleared it, and then the other engine was hesitating when I got up to speed.

On Sunday I changed the filters again and after a brief airlock hiccup when my friends arrived, the boat was perfect all day. But there is an ongoing niggle in the back of my mind.

My point is I’ll never not use a chemical again.

If you buy fuel from premier it is pre dosed with soltron. And I’m told soltron and the marine 16 type are incompatible.
I’m also told by the diesel polishing company in shamrock quay that they have not had to polish the fuel from a premier based boat.
On that basis I’m now using soltron but I doubt it matters which one you use if you don’t mix and match.

Summary
It’s like using a seatbelt, you won’t be glad you were until you need it.
Choose a brand and stick to it.
 
If you buy fuel from premier it is pre dosed with soltron. And I’m told soltron and the marine 16 type are incompatible.
.

Marine 16 diesel fuel complete causes the water to drop out and sit at the bottom of the tank
Presumably Soltron combines water with the fuel ?
So the two are opposing actions.

Having said that the treatments are intended for microscopic quantities of water . No treatment will deal with a significant amount of water in fuel.

You do make a very god good point that the treatment used at the supplier is significant. I do tend to add fuel at different locations during a typical year and presently have no idea what treatment they add , if anything .
 
Marine 16 diesel fuel complete causes the water to drop out and sit at the bottom of the tank
Presumably Soltron combines water with the fuel ?
So the two are opposing actions.

Having said that the treatments are intended for microscopic quantities of water . No treatment will deal with a significant amount of water in fuel.

You do make a very god good point that the treatment used at the supplier is significant. I do tend to add fuel at different locations during a typical year and presently have no idea what treatment they add , if anything .

Yes I had heard soltron dissolves the water which supports what you say.
As I have no way of draining the bottom of my tank (how stupid is that?) then I guess soltron is a good solution for me - stopping any build up of water in the first place (assuming no inrush as you say)
 
And I’m told soltron and the marine 16 type are incompatible.
Who told you this ?
Not compatible in what way ?
Will it blow up 90 grands worth of engines?
I have just bought a boat with full tanks from the south coast, I haven't a clue where it was filled with diesel and I am about to put marine 16 in the tanks,
there is no warning on the marine 16,
is there any warning on the premier pump?
 
Who told you this ?
SDM Fuel solutions in shamrock quay
Not compatible in what way ?
They render each other ineffective (or less effective) as I understand it. MartynG's explaination makes sense.
Will it blow up 90 grands worth of engines?
I don't see why.
I have just bought a boat with full tanks from the south coast, I haven't a clue where it was filled with diesel and I am about to put marine 16 in the tanks,
there is no warning on the marine 16,
is there any warning on the premier pump?
don't know I get discount at MDL so fill there not at premier.
 
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