Find diesel bug

Seastoke

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Hi when i get my boat delivered on thursday subject to sea trial monday touch wood,she will need fill in up with diesel of course but how do i know it does not have the bug and ruin the diesel i put in .help
 
Hi when i get my boat delivered on thursday subject to sea trial monday touch wood,she will need fill in up with diesel of course but how do i know it does not have the bug and ruin the diesel i put in .help

What makes you think you may have 'the bug'?
BUT
If there is enough fuel in for a quick sea trial before you fill up
Take the vessel up to full chat as soon a possible and keep her there as long as the current fuel load will permit
'Bug' shows up when a motor is worked
IE - cos of bug fuel can't get through basically
Can on tickover and pootlin
If she runs fine flat out for as long as you can
Good chance their aint no bug
Apart from that
You can only inspect the filters/ glass filter inspection bowls etc if She has them
Or get a sample of fuel from the depths of the Tank/tanks to get any crud checked
The symptoms of Bug under running conditions?
1 Engine won't gain full revs
2 Engine will emit excess smoke (dark/black usually) especially as the turbo (if She has one) tries to kick in
3 pretty obvious, 'boat speed' won't happen
4 Vendor/ seller will have egg on his /her face and start to blush
;)
 
I assume the boat has diesel engine/s?

Check fuel prefilters for water/ black dust or slime.

Is the diesel clear

Does the diesel smell of anything other than diesel

If you can draw a sample of fuel from the bottom of the tank and look at it in a clean white bowl or plastic paint kettle.

If it looks ok do a seatrial and check the prefilters again after a good run
 
Treat for fuel bug anyway.
I use Marine 16
Since getting the bug about 18 months ago, Marine 16 has cleaned the complete system and kept it clean.

would i be better off using this marine 16 treatment, i need to fill both tanks on my s37 one is just in the red and one just below half need to fill both ready for the winter dont think i have any problems but would i be better using this as prevention rather than cure ????
 
don't panic - you probably haven't got it unless you have black slime on the primary filters. If you are concerned just dose up the diesel with one of the various anti bacterial fixes - grotomar, soltron marine 16 etc.

there are lots of expensive scare stories about it just like osmosis.

when you get the boat don't fill it completely - go to 1/2 to 3/4 on each tank with a good dose of diesel medicine and go for a short blast. this gets the diesel all swirling around with the medicine and should kill any bug residue. Leave the fuel to settle for @ 5 days or so to let the medicine do its work and go for another blast. Do this for the next 3 or 4 fills and make sure you have 2 or 3 spare filters for each tank as they will bung up fairly quickly with dead bug. Its a good idea to practice changing your fuel filters and bleeding the engines in the marina before you go too far from home. If they don't bung up you haven't got it
 
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Personally I would, after catching the bug with the old boat i didn't want to take any chances so when we picked up our "new to us boat" earlier this season I fired in a bottle of the magic bug killer treatment that SeaStart recommended with the first fill up as a precaution and i have been using the treatment with subsequent top ups. I got the stuff from SeaStart at Hamble Point, I think it is Marine 16.
 
i dont think i have got it well i am 99% certain i havn't but was wondering is it best to add some marine 16 when filling up anyway to stop me getting it in the future ????????

Lanerboy,
I was asking the same question recently and when I saw the price of Marine16 it was a no Brainer really. Not expensive, so why not dose with it and sleep easy?
Andrew
 
I assume the boat has diesel engine/s?

Check fuel prefilters for water/ black dust or slime.

Is the diesel clear

Does the diesel smell of anything other than diesel

If you can draw a sample of fuel from the bottom of the tank and look at it in a clean white bowl or plastic paint kettle.

If it looks ok do a seatrial and check the prefilters again after a good run

Knowing you've dealt with diesel bug in may boats, which version of Grotomar do you recommend?
 
Look at Grotamar 82 which is one of the few that is fully compliant for EU Biocide regs, its a top performer and is specialy formulated for mineral diesel and biodiesel, as the latter is now in the supply chain.

http://www.echamicrobiology.co.uk/shop/grotamar82/3,16,0,0/default.aspx

One litre treats 4,000 in normal preventative use and 2,000 for decontamination dosage about £34 in the uk a litre.

After the seatrial check the prefilter Racor/Separ/Volvo Penta/Fleetguard etc and see :

How clean the element is, if its a Fleetguard or a sealed cartridge type you will have to hack saw it open ( not on the kitchen table) if there is slime or strings of gunk = bug

How clean does the fuel look, it should be clear, clean and sparkly, if it is cloudy or opaque or emulsified you have a problem

If you can use a Pella type vacuum pump and draw a sample from the botottom of the tank or the sump if it gas one and look at it in a clean white plastic container or paint kettle , do you see slime strings or water.

You can get a fuel test kit from the above website or they can test it for you

If the fuel in the tank is badly contaminated get a contractor to filter it for you of if a small ammount it may be cheaper to dump it, clean the tanks and replace it.

And above all in the future use a good Biocide fuel treatment such as the above with every filling as a preventative.
 
Look at Grotamar 82 which is one of the few that is fully compliant for EU Biocide regs, its a top performer and is specialy formulated for mineral diesel and biodiesel, as the latter is now in the supply chain.

http://www.echamicrobiology.co.uk/shop/grotamar82/3,16,0,0/default.aspx

One litre treats 4,000 in normal preventative use and 2,000 for decontamination dosage about £34 in the uk a litre.

After the seatrial check the prefilter Racor/Separ/Volvo Penta/Fleetguard etc and see :

How clean the element is, if its a Fleetguard or a sealed cartridge type you will have to hack saw it open ( not on the kitchen table) if there is slime or strings of gunk = bug

How clean does the fuel look, it should be clear, clean and sparkly, if it is cloudy or opaque or emulsified you have a problem

If you can use a Pella type vacuum pump and draw a sample from the botottom of the tank or the sump if it gas one and look at it in a clean white plastic container or paint kettle , do you see slime strings or water.

You can get a fuel test kit from the above website or they can test it for you

If the fuel in the tank is badly contaminated get a contractor to filter it for you of if a small ammount it may be cheaper to dump it, clean the tanks and replace it.

And above all in the future use a good Biocide fuel treatment such as the above with every filling as a preventative.

I was under the impression that you add the treatment direct to the fuel in your tanks and it will cure the problem thus avoiding extracting or dumping the fuel- or have i got this wrong??
 
Mike K

Firstly you need to remove the water or you will get the problem in the future.

Then its a matter of degree of contamination.

Mild contamination, treat and it dies and you will eventually collect it in your filters and get rid of it that way.

Severe contamination it will die off, drop to the bottom of the tank and can block your fuel pick ups so best get it filtered by a contrator ( polished) and put back in the tanks, samall quantities rather than pay a call out charge for a contractor it may be cheaper to dump it yourself , clean tanks and replace with new clean fuel and a biocide.
 
Hi when i get my boat delivered on thursday subject to sea trial monday touch wood,she will need fill in up with diesel of course but how do i know it does not have the bug and ruin the diesel i put in .help

You can get a bug testing kit from your friendly Chandlers.

As others have said, I always treat when filling with diesel, and keep the tanks full over winter so there is less room in the tanks for condensation to form.
 
i dont think i have got it well i am 99% certain i havn't but was wondering is it best to add some marine 16 when filling up anyway to stop me getting it in the future ????????

Lanerboy I understand you filled up @ Cowes earlier today so you should have no prolem also fyi they do not use bio fuel and have a big turnover off fuel so is always fresh and not been hanging around for months :D
 
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