A 'can't fail' diesel bug treatment needed urgently

BobnLesley

BobnLesley

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We've shipped some dodgy fuel/water and appear to have a serious diesel bug problem, particularly serious as we're shortly due to make a passage through the Panama Canal; a breakdown/stoppage through there will cost us thousands in penalty & towing fees.

I know that we can't get the tank steam cleaned and have yet to discover what if any biocides are available here, but am fairly certain that I'll get something, even if I need to traval across to Panama City to get it.

The tanks probably only got 20-30 litres of diesel in, so I'm not bothered about trying to save that, I'll just pump it out and dispose of it. The tank has an inspection hatch, but acess is still going to be poor, I can reach/wipe perhaps 50% of the inside surface at best, though I could probably get a spray (I've had petrol suggested?) to 90% of the internal surfaces. I also have spare pipes, pumps, etc that would enable me to circulate the fuel without it having to go through the filters or engine.

So, any suggestions? I'll no doubt get the opportunity to motor the boat around for a few hours after treatment, let it sit for a day or two and re-check the tank, but shortly thereafter will have to commit to the must not fail passage through the canal.
 
As an bit of an aside, fitting a vacuum guage would help you to manage the situation if it starts to go wrong. There's a similar-ish situation in NI when going up to Belfast Marina. Breaking down in the main shipping channel risks at least a lot of embarssment and potentialy a bit of a rough tow out by the pilot boat.

With a vacuum gauge you know if the filter s starting to block and have more opportunity to change it at a more convenient time. At sea once I managed to pull off a CAV filter change without stopping. i.e. stop the engine briefly, put fuel pipe into a 22l can, change filter, stop engine briefly and pull the fuel through the filter without bleeding (I didn't actually expect to get away with the last one but did). I had to keep going as I was heading for a tidal marina at the time.

PS re the main question, I suspect you might just end up having to make the best of whatever bug killer you can get, hence the thinking behind the post above.
 
It's 50 miles?
10 hrs of motoring at 3l/hr?
Maybe think in terms of a backup system using cans.

If the system is really dirty, addng biocide is just going to turn crud into dead crud. The key is to reduce the total amount of crud, dead or alive, to significantly less than the filters can cope with.
I would keep pumping from the bottom of the tank through a filter and back until it runs clean.
Biocide is only really useful for preventing a small amout of crud getting bigger over time.
 
BobnLesley said:
We've shipped some dodgy fuel/water and appear to have a serious diesel bug problem, particularly serious as we're shortly due to make a passage through the Panama Canal; a breakdown/stoppage through there will cost us thousands in penalty & towing fees.

I know that we can't get the tank steam cleaned and have yet to discover what if any biocides are available here, but am fairly certain that I'll get something, even if I need to traval across to Panama City to get it.

The tanks probably only got 20-30 litres of diesel in, so I'm not bothered about trying to save that, I'll just pump it out and dispose of it. The tank has an inspection hatch, but acess is still going to be poor, I can reach/wipe perhaps 50% of the inside surface at best, though I could probably get a spray (I've had petrol suggested?) to 90% of the internal surfaces. I also have spare pipes, pumps, etc that would enable me to circulate the fuel without it having to go through the filters or engine.

So, any suggestions? I'll no doubt get the opportunity to motor the boat around for a few hours after treatment, let it sit for a day or two and re-check the tank, but shortly thereafter will have to commit to the must not fail passage through the canal.
Click to expand...

get yourself a nice clean plastic jerrycan of 5 galls or more, fill that with clean diesel and run the canal using that.

I have had diesel bug in every boat I have had and have always got rid of it but its time consuming and I used all the facilities available to me in civilisation not central america. I simply wouldnt risk a hurried solution and the possibility of having to argue with some gun toting third world official in a language I wasnt fluent in. The risk reward ratio is all wrong.
 
When I got diesel bug in an inaccessible keel tank, I made a fuel polishing system using an old water pressure pump and a CAV filter. Just kept circulating the fuel, returning it to the tank with a directional jet so I could try to dislodge crud. It worked. But, as lw395 points out, it's not far and you could easily arrange a temporary system to get you through the canal.
 
wotayottie said:
get yourself a nice clean plastic jerrycan of 5 galls or more, fill that with clean diesel and run the canal using that.
Click to expand...

Of course the OP should also be aware of the return pipe. A 22l can will give me about 30 mins even though probably only a litre or two of that gets burnt in the engine, but other boats are probably better. Taking the return pipe back to the can is one solution, especially if you don't really trust the contents of the tank, but the stuff in the can could get quite warm.
 
wotayottie said:
get yourself a nice clean plastic jerrycan of 5 galls or more, fill that with clean diesel and run the canal using that.

I have had diesel bug in every boat I have had and have always got rid of it but its time consuming and I used all the facilities available to me in civilisation not central america. I simply wouldnt risk a hurried solution and the possibility of having to argue with some gun toting third world official in a language I wasnt fluent in. The risk reward ratio is all wrong.
Click to expand...

I agree, get some fuel in cans. Might be an easier connection with an outboard tank if one could be acquired.

Don't forget to connect the return to the can/tank too.
 
Not an immediate cure, but get some Marine 16 and chuck a good dose of it in your tank. This will kill the bug.

You'll also need to buy 3 or 4 primary fuel filters as they will get blocked pretty quickly as all the crud finds its way through.

Best of luck.
 
Can you not drain the tank through the fuel feed before it reaches the filter (or better still a drain plug if you have one) then wash it through with a small amount of fresh diesel, finally adding enough to get you through? Obviously you’ll have traces of the bug still in the tank but adding some marine 16 and the fact that it probably just takes a day or two to get through the canal (never done it myself) means it’s unlikely to grow again in such a short time I would think.
 
I had bug problems. In the end I installed to fuel filters in parallel. Both could be isolated. If one failed it was a quick thing to isolate it, open the clean valve and replace the contaminated filter. Fairly unlikely that you will have a problem through canal as bug stays settled in bottom of tank and tends to only cause a problem if disturbed in rough seas (the worst possible time). Clean the tank out thoroughly and avoid water or dirty fuel. My problem was that I washed the decks down with fuel cap off!!
 
I think the canal pilots require you to keep the engine running when in locks - they did when I transited it way back - it could make for a long day or two if you're uncertain about your fuel supply.

I used Biobor JF which was recommended by Calder at the time. Never had a problem - even when others were suffering from the same bad fuel supplies.

According to Biobor stockist list nothing is available in Panama City/Colon - nearest place is Budget Marine in the ABCs.

Budget Marine Curaçao - Caracasbaaiweg
Caracasbaaiweg 202
Curaçao
Phone: +5999-462-7733

or Aruba

Budget Marine Aruba
Balashi 75-B, P.O. Box 162
Oranjestad
Phone: +1-297-585-3796

Maybe hold back on the transit and get a fellow cruiser to bring some across.
It's still quite early in the season if you're doing the usual Marquesas run.

HTH

Edit: Received this message from Ran Sailing yesterday who have just transited -
"Yesterday we heard of a boat that got gearbox failure in the Gatun lake. They had to pay a delay fee of 500 dollars per day while waiting for repairs. In the end they ended up paying over 5000 dollars in fees! "

So you're right to worry!!
 
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Bobc said:
Not an immediate cure, but get some Marine 16 and chuck a good dose of it in your tank. This will kill the bug.

You'll also need to buy 3 or 4 primary fuel filters as they will get blocked pretty quickly as all the crud finds its way through.

Best of luck.
Click to expand...

I would not add treatment to a known dirty tank.
See the grey diesel thread last week.

I would look at either polishing the fuel or simply sucking the dirt and water from the bottom with a Pela or similar.
When the fuel is as clean as you can get it, then consider adding treatments.

The first couple of tanks I cleaned, a Pela with bigger bore hose did the job quite well. I sucked out all the loose dirt and water from the bottom of the tank (heeling the boat to send the heavy stuff to one side). Took out about 15 litres of dirt and diesel. After a couple of days it had settled enough in cans to return half of it to the tank via a filter.

Later I and a mate built a simple polisher. Some filters and a pump.

The object of the game is to have less crud in the system than can possibly block the filter. With a margin.
In my view there is not much benefit in getting it surgically clean as it won't stay that way.
Neither would I want litres of water and kilos of dead crud dispersed in the tank.
 
Forget biocides at this time. Clean the tank as best you can, pump out the muck, clean again...agitate as best you can where you cant clean, pump out the muck, add small quantities of fuel, slosh around...pump out. A few passes of that sort of sequence so that what comes out is fairly clean and you should be good to go.
BUT do take the extra in containers as belt and braces.
If you have to stop then having the resources to get going again quickly should ensure that any charges are not too great.
Horrible setting off on an adventure with a worry on your mind, let us know how it went.

Good luck
 
pcatterall said:
Forget biocides at this time. Clean the tank as best you can, pump out the muck, clean again...agitate as best you can where you cant clean, pump out the muck, add small quantities of fuel, slosh around...pump out. A few passes of that sort of sequence so that what comes out is fairly clean and you should be good to go.
BUT do take the extra in containers as belt and braces.
If you have to stop then having the resources to get going again quickly should ensure that any charges are not too great.
Horrible setting off on an adventure with a worry on your mind, let us know how it went.

Good luck
Click to expand...

Peter
you got it in one! As lw said, a pela is your best friend, even removing the fuel level guage transmitter gives enough room to get the pela tube in. I tied the big hose part, not the bowden cable outer one, to a thin stick to be anle to manipulate the end to chase bits. Clean the crud out best as, then clean diesel with bio and jerry cans with fuel feed and return hose and a plan! just in case.
Stu
 
You'll be aware that if running your engine from fuel in a can consumption might be twice what you expect. Up to 50% of the fuel drawn from the can will be "returned" to the main tank - unless you are really clever and reroute the return pipe to the can.
Good luck.


Edit: Should have read the whole thread!:o
I "became aware" when using 20 litres of diesel from a can as an emergency "get me home" measure. I nearly had to get the sails out...
lpdsn said:
Of course the OP should also be aware of the return pipe. A 22l can will give me about 30 mins even though probably only a litre or two of that gets burnt in the engine, but other boats are probably better. Taking the return pipe back to the can is one solution, especially if you don't really trust the contents of the tank, but the stuff in the can could get quite warm.
Click to expand...
PaulRainbow said:
I agree, get some fuel in cans. Might be an easier connection with an outboard tank if one could be acquired.

Don't forget to connect the return to the can/tank too.
Click to expand...
 
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A1Sailor said:
You'll be aware that if running your engine from fuel in a can consumption might be twice what you expect. Up to 50% of the fuel drawn from the can will be "returned" to the main tank - unless you are really clever and reroute the return pipe to the can.
Click to expand...

I've rigged up a temporary supply from a jerry can plus a return when at sea when I had to. Without a return the fuel will soon go, don't forget that it needs to go through a filter as well. It's simple as long as the OP does it before there's any pressure and ensures he has all the necessary hoses and fittings. The other option is a dual filter system with a changeover but bug can block even supply pipes.
 
The existing/contaminated fuel's not the problem, I've pumped that all out and this afternoon's job is to wash/flush out the tank and all the supply pipework with industrial alcohol; I'm assuming/hoping that if I then leave the tank dry & empty for a couple of days (pehaps with a couple more alcohol flush-outs) surely any of the little buggers remaining should have died? I then intend to partialy refill using fresh diesel with some Starbrite biocide added to it - a boat further up the pontoon's got a spare bottle of that. After which I will probably leave the tank to stand for a couple of days before reinspecting and hopefully seeing no re-growth. An extra week's marina fees will be peanuts compared to a mid-canal breakdown. I like the temporary tank idea, it's what we used to get in here, but with the two of us, three additional line handlers and a canal-advisor on board, there simply won't be enough space to set that up and maintain it for the duration.
 
I think it depends on how empty and clean you can get your tank.
Some tanks seem to come up shiny after many years, others grow a layer of tar-like stuff. If there is a lot of tar, I'd either want to leave it firmly in place or totally get rid of it.
I would be slightly worried about solvent like alcohol making this stuff mobile and taking it through the filters.
I would be wary of getting solvent into the fuel line to the engine unless I was confident of finishing the job, getting the lines spotless, without sending any dissolved tar to the injectors.

I think in your position, before going into the canal, I would want to have completed a few hours running and found the filter fairly clean at the end of it.
In my view there is no real substitute for seeing clean diesel circulating around, which is why we built our polisher.

The crud we find in our tanks is quite varied stuff. I can't guarantee that yours will be exactly like the tanks I have dealt with.
Final thought, is the alcohol OK with the lift pump diaphtagm and any other rubber bits?
One of my boats, when I bought it, there was sealant in the fuel system, which was slowly being eaten by red diesel, I hate to think what alcohol might have done.
 
I'm not going to pump the alcohol through the engine, just wash/flush the tank, then circulate through the pipework and primary filter/water seperator; I've got those all removed from the engine and the system reassembled independently in the cockpit, I'll circulate the alcohol through them for a half hour, before a final flush with fresh diesel and a new filter. The engine itself I'll just circulate fresh diesel/biocide through.

I will certainly be running the engine for several hours and several times before contemplating heading for the canl; I want it to sit for a day or two between times too, to see if there's any regrowth, the tank looked 'clean' last Tuesday morning, today I'd say there's white/brown/black sludge coating perhaps 40% of the visible tank-floor.
 
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