Have I got diesel ??

jaminb

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Thanks for confirming , sounds like I am bugged !

Been using Marine 16 and the one that looks like tea. No evidence of bug last year when I inspected the bottom of the tank, have topped up twice over the season so probably used 50 litres of a 130 litre tank.

time to build a polisher and clean that tank - oh joy. The biggest issue is resealing the inspection hatch with self tappers, into a thin plastic tank, with no backing plate. It has leaked under pressure since I disturbed it last year. Any ideas ?

thanks
 

superheat6k

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Thanks for confirming , sounds like I am bugged !

Been using Marine 16 and the one that looks like tea. No evidence of bug last year when I inspected the bottom of the tank, have topped up twice over the season so probably used 50 litres of a 130 litre tank.

time to build a polisher and clean that tank - oh joy. The biggest issue is resealing the inspection hatch with self tappers, into a thin plastic tank, with no backing plate. It has leaked under pressure since I disturbed it last year. Any ideas ?

thanks
My approach o get a better seal would be as follows.

Replace the self tappers with small (say M6) rivnuts then make a rubber gasket with the holes just larger than the heads of the rivnuts. Bed both sides of the rubber gasket with a non hardening sealant such as hylomar. Use a large washer under the head of each M6 bolt to spread the bolt load. If you can get your fingers in to the back of each hole then add another washer behind each rivnut too.

I have recently installed a polishing system using a Racor 500 copy filter and Aeroflow Black fuel pump from eBay. It is important to draw the fuel first through the filter then to the pump. If you pump first any water droplets are smashed into tiny particles that become too small to coalesce at the filter. The rig can be put together for ~£200..
 
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Refueler

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The biggest issue is resealing the inspection hatch with self tappers, into a thin plastic tank, with no backing plate. It has leaked under pressure since I disturbed it last year. Any ideas ?

That is NOT your problem and TBH .... just use some sealant when refitting hatch.

OK - your 'bug' problem ...........

Yes it appears you may have a bug problem ... so I would :

1. Siphon out as much of the BOTTOM of tank as possible
2. Add ENZYME based additive to a serious dose level the fuel remaining in tank
3. Change filters.

You may need to change filters again .... but main factor is to use a serious dose of Enzyme based additive .... to break up the dead bug residue ...

Note : LIVE bug is a problem - but not what clogs filters and stops the engine, Its the DEAD bug that does that. So an additive that breaks it down is what is needed.

One day people will understand this fundamental factor,
 

jaminb

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Thanks everyone. When I said inspection hatch I meant the hole for the sender unit as this is the biggest and also at the tanks deepest point and hopefully where the water and bug are. The ring of studs sounds the best solution but stretching my fabrication ability ! I was thinking two semi circle plywood backers held in place with some tiny self tapers and then the existing self tappers screw into that? Any ideas how ply reacts with diesel?
 

Rum Run

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Thanks everyone. When I said inspection hatch I meant the hole for the sender unit as this is the biggest and also at the tanks deepest point and hopefully where the water and bug are. The ring of studs sounds the best solution but stretching my fabrication ability ! I was thinking two semi circle plywood backers held in place with some tiny self tapers and then the existing self tappers screw into that? Any ideas how ply reacts with diesel?
The two semicircles sound like a plan, but I'd use polypropylene or polyester for them, not plywood. The customary source for these exotic and highly technical materials is..........

A plastic chopping board
 

westernman

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When I had the bug, I used Grotamar which also breaks down the dead bug as well.
Worked fine without having to dump any fuel or clean out the tanks.
I had to change filters a couple of times of course.

You might want to try that before resorting to doing something more complex than chucking a bottle of magic chemical into the fuel tank.
 

Refueler

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No.

Sorry but as I say - you cannot cure ... you can only reduce and control.

Think of it like this :

1. You have fuel in tank - you dose it - you kill the bug.

2. You top up tank when you are running out - bug gets re-introduced.

You are back to #1 .....

The remedy is to control it by regular doses of additive to keep it down.
 
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When a previous boat running red diesel had the bug I was able to remove and clean the tank. Final clean was with petrol which done the trick, then cleaned with diesel. All pipes were stripped out and replaced with plastic sleeved soft copper pipes. New fuel and marine 16 added. Never had a problem afterwards. I only use fuel station white diesel as there have been too many marina fuel horror stories.
 

superheat6k

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I have not added any additive in any of my last four power boats (nor in several destroyers / frigates before them). the fuel itself already costs enough, and IMHO there is no need to add any snake oil on top.

The issue is keeping the fuel dry i.e. no moisture. The bug cannot live in the fuel itself - that is it's food. It lives in the water where it meets the fuel. So keep the fuel clean and dry and you have no bug / bug residue.

I know one poster will never agree with this. But regular polishing has worked for me for the past 16 years since I bought my first power boat with a serious sized engine.

My latest boat has a light layer of crud, likely dead bug, laying below the take off point (I know this because I have observed a light build up of black strands in the base of the Racors. I have been polishing for ~ 3 months now since I installed my polishing system, and so far not much has come out. I can either spend an age opening and deep cleaning the base of the tanks, or simply keep polishing after each trip and stir up of the tanks. Each engine has large Racor 900 dual filters, so risk of a fuel blockage affecting service is quite low. This is not something that concerns me, and I am satisfied my fuel is sufficiently dry, so the issue will not get worse.
 

Refueler

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I have not added any additive in any of my last four power boats (nor in several destroyers / frigates before them). the fuel itself already costs enough, and IMHO there is no need to add any snake oil on top.

The issue is keeping the fuel dry i.e. no moisture. The bug cannot live in the fuel itself - that is it's food. It lives in the water where it meets the fuel. So keep the fuel clean and dry and you have no bug / bug residue.

I know one poster will never agree with this. But regular polishing has worked for me for the past 16 years since I bought my first power boat with a serious sized engine.

My latest boat has a light layer of crud, likely dead bug, laying below the take off point (I know this because I have observed a light build up of black strands in the base of the Racors. I have been polishing for ~ 3 months now since I installed my polishing system, and so far not much has come out. I can either spend an age opening and deep cleaning the base of the tanks, or simply keep polishing after each trip and stir up of the tanks. Each engine has large Racor 900 dual filters, so risk of a fuel blockage affecting service is quite low. This is not something that concerns me, and I am satisfied my fuel is sufficiently dry, so the issue will not get worse.


I know you are referring to me ...

Just to give an example - seeing as you mention 'ships' ................ Entering Red Sea on a 35,000 DWT Product Tanker "Petroship A" - we had to send a message to Petromin, (Owner Operators) that we needed to stop at southern entrance to Suez and clean the main engine, completely change the Lub Oil with new.
As you should know - I bet your Grey Funnels did it as well ..... ships Lub Oil is regularly filtered / centrifuged during its life. We had found large amounts of gel and 'paint' in the residues. We stopped ship and drifted while engineers entered the main engine sump. Yes engine - B&W - is that big. The sides of the sump had its lining sliding down in sheets where BUG had got behind ..
No water detected at all. It was my introduction to Bug and also the SRB version.
Later when I came ashore to work in SGS - I took on every course / learning curve I could to expand my knowledge of Petrochems. This led onto my ownership of labs and inspection co's.

My companys have been involved in all manner of Fuel related matters from Blending, Improving, Treating, Testing, Inspection.

Bug breaks down into 3 + 1 categorys :

3 are : Yeats Moulds and Bacteria - we just call it YMB
The +1 is the odd one out that is SRB ... Sulphur Reducing Bacteria - which in fact needs no moisture at all ... it can live at any level in petroleum.

What most people do not realise - is that Bug can infect many different petroleum products from light to heavy distillates including Lubricating Oils.

I applaud your optimism but I hope that newcomers to this matter follow a safer path and use the additive ... it is NOT Snake Oil ... it has a definite and beneficial function. Far more effective than any Polishing setup.

I haven't been in this business for most of my working life to then pass on false advice.
 
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