Diesel Bug Treatment

[Irish Rover]

I had a problem with water in one of my diesel tanks at the end of last year Engine Problem - help please. The engine has done over 100 hours since without any issues until last Thursday. I was on my way home from a week long trip and I encountered very rough weather and took a fair buffeting motoring into big waves at around 7kts. I usually motor on just one engine but in heavy seas I use both. Around 45 minutes after starting the port engine it stuttered a bit and then shut down. I didn't try starting it again and continued on one engine. When I was able to take shelter I had a look in the engine compartment and saw nothing amiss. No leaks and engine oil and coolant level normal. I decided to be cautious and continued home on one engine. I did start the engine in the marina for maneuvering and it seemed to run ok. I asked my mechanic to come have a look and when he revved in neutral the engine stuttered and died. Fuel starvation and on inspection the first inline filter was clogged with a snotty mucous type substance. He changed the filter and the engine ran smoothly. There was no water or contamination in the racor separator. I took the boat out for a spin this morning and ran the port engine for around 1 hour. When I checked the filter had a build up of mucous again, though not as bad as the first and the engine ran smoothly.
Diesel bug is not common here in Turkey and the mechanic suggest that changing the filter regularly for 3/4 turns should solve the problem. I'm not convinced and plan to treat the fuel. Because bug is not common here there isn't a huge range of popular treatments available. I found a PBO article from 2016 12 diesel bug treatments tested - Practical Boat Owner and searched for the products they tested. The only 2 available are
Grotamar 82
was developed to combat problems from low-sulphur biodiesel blends, and achieves its aim well. The 92% kill rate is good, and the sample proved the swiftest of the biocide-treated fuels through the filter. The product did a good job of dispersing the water into the fuel, although this is not its primary purpose. There were some minor deposits left in the bottom of the flask.
and
Star Tron.
Among the best on test with a 96% kill rate, Star Tron also excelled with a 47% improvement in filter speed. However, it did leave some sticky deposits in the jar and had not completely dispersed the water. Starbrite say that their product is most effective when the boat is used, as the engine will then process the treated fuel and destroy the bug.

So my questions
- does anyone have any experience of using either of these products or which would you recommend I use?
- for the shock treatment should I dose the remaining fuel in the tank [around 30% or 120L from a capacity of 400L] run the engine regularly for a few days and then fill the tank while adding a maintenance dose or should I add a shock treatment for a full tank and fill the tank now.
- any other suggestions or recommendations.
Sorry for the long post and thanks for taking the time to read it.

 

[pvb]

Of those two, I'd choose Grotamar.

I'd add a shock dose for the remaining fuel, then add another shock dose when you next fill the tank.

 

[rib]

Of those two, I'd choose Grotamar.

I'd add a shock dose for the remaining fuel, then add another shock dose when you next fill the tank.

I agree with pvb mate. Hit it hard while low on fuel then again after refilling.. FYI I always use additive regardless of what country I'm in. Even UK have known of bad fuel from Weymouth. Dover. Personally all be it a few years ago now.... Warning.. It can be expensive!!! But not as expensive as with out ??.

 

[Biggles Wader]

Apart from the treatment do you have any means of cleaning out your tank? If the problem arose in rough weather it is probably due to muck being disturbed in the tank and the only sure way to sort that is to get rid of it.

 

[robmcg]

I would use the Startron stuff. The Grotamar stuff tends to produce prodigious amounts of solids as it kills off the bug. I think it was developed for large storage tanks initially. The Startron we have used for over 10 years and has been great.

 

[Refueler]

Because I cannot get industrial we use for ships in small volume and breaking seals on our containers would bring about customs issues ... to keep life simple - I buy additive as you would ..

What do I use ?

If I can get to UK - I will usually buy FuelSet ... but if I need to online order from EU supplier - then its Startron.

I add a small amount to each fill up just to maintain system.

For OP - I would first of all try to suck out the bottom of the tank ... both would be good idea .... when fuel is seen coming through clear - then you can stop.

Add a dose of what additive you decide to each tank.
Change filters.

You could if wanted - let the syphoned fuel settle ... decant of the clearer fuel and dose that to clear ... once clear decant to tank.

Discard the goop of course ...

If you use something like Startron after sucking out the bottom of tank - you can basically forget all that 'Fuel Polishing' malarkey that people seem so convinced of .....

 

[pvb]

If you use something like Startron after sucking out the bottom of tank - you can basically forget all that 'Fuel Polishing' malarkey that people seem so convinced of .....

If the tank is badly contaminated, cleaning it is the only realistic solution. Startron won't magically clean it.

 

[Refueler]

If the tank is badly contaminated, cleaning it is the only realistic solution. Startron won't magically clean it.

I agree on that - but Fuel Polishing ?? Running fuel through filters that are actually greater size than the problem they say they solve ??? Trouble is so often posts are made on threads like this advocating FP to clean up the FUEL ...

Cleaning a tank - YES - I agree ..... never said Startron or any other would clean the tank ...

Did I not suggest sucking out the tank till fuel comes through clear ??

 

[pvb]

I agree on that - but Fuel Polishing ?? Running fuel through filters that are actually greater size than the problem they say they solve ??? Trouble is so often posts are made on threads like this advocating FP to clean up the FUEL ...

Fuel polishing is a good and proven method of removing crud from the tank, especially when tank baffles prevent easy access to the bottom. When I experienced diesel bug some years ago, I rigged up my own fuel polishing system, using cheap CAV filters, and got rid of the problem.

 

[Refueler]

Fuel polishing is a good and proven method of removing crud from the tank, especially when tank baffles prevent easy access to the bottom. When I experienced diesel bug some years ago, I rigged up my own fuel polishing system, using cheap CAV filters, and got rid of the problem.

Good ... glad you succeeded.

You miss the point I made ......... YOU cleaned your tank by I assume filtered circulation ...

The FP that is quoted by many is to clean FUEL ... to supposedly create good clean fuel from contaminated.

Two different matters .................. my original point made was to pre-clude the usual suggestion of FP to clean Fuel.

 

[Hacker]

Get a Fuel Dipper from Marine 16. This will clean out any water before it starts to cause problems. If you then use their Diesel Bug treatment to kill anything left and their Complete to keep the fuel in good condition.

 

[robmcg]

Get a Fuel Dipper from Marine 16. This will clean out any water before it starts to cause problems. If you then use their Diesel Bug treatment to kill anything left and their Complete to keep the fuel in good condition.

Expensive for what it is. If you want to remove water and crud before your primary fuel filter you could fit a fuel guard for a quarter of the price. It too has a removable, washable filter but without the pump bit. Helps if your tank is above the engine.

 

[Hacker]

Maybe, but it does it actively compared to a passive filter. I wasn‘t saying he had to get one but merely alerting him to the option.

 

[Sandy]

I am fastidious since getting the fuel bug a few years back.

I alway filter my fuel with a 'Mr Filter' you will be amazed at the amount of craXp that it collects. Slow, but I'd rather spend the time filtering fuel than trying to getting into a difficult harbour and worrying about the quality of my fuel.

 

[Refueler]

WOW !!!!!

I know it can be a nightmare and lead to serious consequences if engine failure ........... but guys !! M16 Fuel Dipper ????

A simple 'reversible' pump ... a hard tube joined to flexi to get into tank ... flexi out from pump to a large plastic drum ...

Pump out tank ... after a reasonable volume in drum ... reverse pump and pump back part - that will cause a stir on the bottom ... then pump back to pumping out.

Empty tank ... settle fuel .... decant off clear fuel ... filter if you think its needed .... dose it .. put it back in tank ...

Blimey ...

 

[Slowboat35]

Just to dispel a few myths...

Adding anything to a tank that is already contaminted with bug will NOT clean it. It may (if you're lucky) kill (most of) the bug that will then settle to the bottom as sludge ready to block your filter.

A bigger filter will probably just take longer to choke on this in rough weather than a smaller one, but choke it is still likely to do.

Polishing fuel cannot remove bug in the tank, it only cleans the fuel. If you return the polished fuel to the tank it's a complete waste of time as you've done nothing to remove the sludge settled on the tank's bottom but the engine will remain happy on the clean fuel - until the filter clogs again.

Solution? Have bug? Merely removing and plishng the fuel is pointess. The sludge won't be removed. Totally empty and blast/scrub tank clean on all internal surfaces inc walls and top. Ensure especially the bottom is totally cleared of crud. If the tank is much baffled then so will you be as there isn't a ready solution bar bigger/parallel filters and lots of bug killer. Fuel removed can be polished and returned to the tank once it's internal surfaces are cleaned off.

Not yet got bug?
...Better. Use additives to prevent it.

Moral? Don't risk it, habitually keep tanks full as full as practical, esp on layup with biocide mixed in.

As with most diseases, prevention is easier and less painful than cure.

 

[billyfish]

SO....I've had bug first time ever...and lucky have inspection hole that looks into lowest part of the tank .3 times I've syphoned out the crap and water from the bottom . Keep hearing people say clean the tank ...but how ? I can get all the fuel out but I cant get behind the baffles..what to flush it with ? How to flush ?

 

[pvb]

SO....I've had bug first time ever...and lucky have inspection hole that looks into lowest part of the tank .3 times I've syphoned out the crap and water from the bottom . Keep hearing people say clean the tank ...but how ? I can get all the fuel out but I cant get behind the baffles..what to flush it with ? How to flush ?

When I had the problem, I pumped out the fuel through a filter into clean 25 litre containers. When the tank was empty, I dumped 25 litres back into the tank as quickly as possible, to stir up the remaining crud. And repeat. And repeat. Took several days, but sorted the problem.

 

[rich]

SOLTRON is not a biocide. It was a very one sided test, done by the laboratory owned by Grotamar, so what did you expect the result to be.

 

[Refueler]

When I had the problem, I pumped out the fuel through a filter into clean 25 litre containers. When the tank was empty, I dumped 25 litres back into the tank as quickly as possible, to stir up the remaining crud. And repeat. And repeat. Took several days, but sorted the problem.

Now we agree .......... similar to my post #15.

We can only do our best to clear a tank ...