Contaminated Fuel

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Paul&Ness

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Hi Guys, I had been planning to take the boat out tomorrow so went down today to do my checks and when checking the fuel/water filter I had a bit of a shock to find the fuel looking brown... normally lovely clean red. Suspect diesel fuel bug not having ever had experience of diesel fuel bug I thought that I would post here. If it is diesel fuel bug do I just treat it, change the filters and carry on as usual or do I get the fuel polished etc.
IMG_2767.jpg
 
Paul&Ness said:
Hi Guys, I had been planning to take the boat out tomorrow so went down today to do my checks and when checking the fuel/water filter I had a bit of a shock to find the fuel looking brown... normally lovely clean red. Suspect diesel fuel bug not having ever had experience of diesel fuel bug I thought that I would post here. If it is diesel fuel bug do I just treat it, change the filters and carry on as usual or do I get the fuel polished etc.
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I'm no expert but it looks like bug to me! How much fuel is in the tank and how accessible is the tank itself (any inspection hatches, etc)? Are you comfortable changing primary fuel filters (sounds like you are)?

Pete
 
Hi petem, the tanks hold 500ltr each and I would think that here are approx 150ltrs in each... Access is possible but difficult as they are on the outboard side of the engines under the salon seating with no direct access from above. I'm happy to change filters etc.
 
When I enquired about having an inspection hatch cut in my Targa 34 tank followed by a tank clean and fuel polish it was looking like £700 (VP Agent) or so. This company has also been recommended to me - SDM (http://sdm-fuelsolutions.com/ ).

As I say again, I'm no expert but surely there can't be anything to lose (other than £30) by giving it a shock treatment (100 ml to 100 litres) of Marine 16 ("Bug Treatment" not "Complete Treatment") and keep a few sets of fuel filters on board in case you get any blockages.
 
I have plenty of spare filters so may buy some treatment tomorrow and give it a go. I have already been on the SDM website so may give them a call anyway to see what they would charge.
 
Put some of the treatment in the sample you have in the jam jar and see if it kills it and what sediment you end up with. Worth a go

Dennis
 
Paul, this looks to me like it needs polishing rather than a shock. A decent fuel polisher should be able to acces through your fillers. Alternative is to bin the 300 litres, start again, and treat the new fuel.
 
If you have fuel bug then you also have water in your fuel tank. The bug develops at the interface layer. Your bowl is showing severe bug so it looks like the layer has reached the pickup tube.

1 The fuel sitting above the interface will likely be clean an perfectly OK.
2 The water and muck at and below needs to be removed. Snake oil won't do this.
3 The water source needs to be identified - most likely the deck filler threads just need greasing.
4 Move all the fuel into one tank, ideally with a simple polishing filter and pump, removing any muck as you go. If you do this from the filler you can initially suck the clean fuel from above the interface, then as only contaminant is being drawn put what's left into drums.
5 Once one tank is empty of liquid you can then draw clean fuel from the top of the fuller tank across to the empty, and use this to stir up the crud layer, which you then suck out again into drums.
6 When you have got most of the crap out then move all the clean fuel across via a clean drum. Filter pump once into the drum, then twice from the drum into the cleaner tank, each time leaving any muck behind.
7 Any drums that have had contaminant added that form a clean fuel layer can have that layer collected, polished and returned to the tank.
8 When both tanks are reasonably clean then add the fuel additive in a shock dose to kill any remaining bug.
9 Then shuttle the fuel tank to tank several times, until it is consistently clean and bright.

Most bunkered fuel will have a water and light bug layer in the bottom of its tank. This does not mean the rest of the fuel cannot be used. It is possible your contamination arrived at a refill. This is why I always polish my tanks after a refill.

The polishing rig can be put together for ~£200 including instant connectors to allow easy connection.
 
Thanks for such a detailed solution. Thats a process I would be willing to have a go at. I have already, today, added some Marine 16 to the sample in the bottle so will monitor how successful that is. I don't suppose you could spec the parts that I would need to put a rig together. I have no work on Monday & Tues so could have a go at this :)
 
Paul&Ness said:
Thanks for such a detailed solution. Thats a process I would be willing to have a go at. I have already, today, added some Marine 16 to the sample in the bottle so will monitor how successful that is. I don't suppose you could spec the parts that I would need to put a rig together. I have no work on Monday & Tues so could have a go at this :)
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Cool, will be good to see the 'after' pics to see if snake oil does work!
 
If you can get at the tank what I did was put a holesaw through and a ring of rivet nuts around and put an aluminium plate over with a 3/8bsp tapping (towards the top and opposite end to the drain) and had a 12v tranfer pump between drain and new tapping going through a 10" filter canister (clear water filter type) and got loads of crud out, a good dose with marine 16 and the bug was gone.
Unfortunately for me the rust was still there and the tanks were still rotten, they are now in my garden awaiting new tanks.
plate.jpg

filter.jpg
 
Pump Mine uses a Holley Red Top pump, and has been in use since I first made it in 2008. These are quite expensive, so I have been looking at this as a replacement if / when needed.

http://www.ebay.co.uk/itm/Facet-Red...e=STRK:MEBIDX:IT&_trksid=p2060353.m1438.l2649

Holley Red top here, but not cheap ...

https://www.ebay.co.uk/itm/HOLLEY-1...706592&hash=item51fae61afc:g:7yQAAOSwFJBZVhGl

For the filter

http://www.ebay.co.uk/itm/BALDWIN-B...472864&hash=item3af583b914:g:8fwAAOSwo4pYLubo

For the rig I find this filter which uses a Baldwin PF10 element more effective than a Racor 500, which largely relies upon flow speed to achieve a simple centrifuge effect. The flow rate achieved with a small pump is too low to get much spin, but the PF10 element has a nice large surface against which the water can coalesce.

It is important to draw through the filter, not pump to it - the action of the pump smashes any water droplets into particles small enough to pass through the filter.

For the instant connections ...

https://www.ebay.co.uk/itm/QUICK-RE...var=590698457071&_trksid=p2060353.m1438.l2649

I use the 3/8" BSP, so for each you also need a suitable adapter to suit the hose you choose, e.g. Gas or petrol hose is OK, plus suitable adaptors to tee into the system. I have also installed a ball valve on each to make sure of positive isolation.

Mine has males on each end of the hoses to the filter and from the pump, with females on the fuel pickup line just before the pre filter, tank low point drain and spill return lines to each engine / tank.

I can draw from one tank and discharge to the other. If I return fuel via the normal pickup line it is able to clear a slug of crud should one ever get picked up, and also partially pressurises the fuel system through the lift pump and on engine filter all the way to the injection pump, which makes bleeding the pre and on engine filters a doddle at change time.

I generally run the unit for about an hour every month or so on each tank, and as long as nothing gathers in the bowl I leave it at that. Since adopting a polishing routine I have never added any fuel additive, nor suffered contamination, although I am careful to keep the filler threads well greased, as this is the most likely point of water entry.

Water gathering through condensation in a partially filled tank beyond a couple of teaspoonfuls over Winter is IMHO a myth.

Fuel%20polishing%20rig.jpg

Fuel%20dripless%202.jpg
 
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Hi Superheat6k

I like the look of your setup, not too expensive and not too bulky either. In the last image; is the ball valve attached to copper pipe?
Thanks for sharing your setup :)

Paul
 
just ran into this problem, the racor separator was full of crud.. I bought a new filter and cleaned the racor and replaced the filter.. As for the crud in the tank, I had no inspection hole that would readily un do, but I was able to disconnect the main filler hose from the deck from the tank. I bought a 12 volt oil removal pump from Lidls, attached a socket to the end of the sucky up side to weigh the hose down and allow it to settle to the bottom the tank and duly pumped out 4 liters of crud.. until I saw red diesel.. not the most elegant fix but for 20 quid including filter, I am quite happy.. I will continue to monitor the racor to see if the problem was fixed
 
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Might it be useful for folk to say where they purchased their fuel? Not necessarily conclusive proof of a problem but might be interesting to see if any patterns emerge. I think 'crossy' had a bug issue recently too.
 
petem said:
Might it be useful for folk to say where they purchased their fuel? Not necessarily conclusive proof of a problem but might be interesting to see if any patterns emerge. I think 'crossy' had a bug issue recently too.
Click to expand...

Perhaps more useful to give a little background on prophylaxis, “ to see if any patterns emerge “ .

I,ve been putting “ snake oil “ - actually Startron diesel additive in at virtually every fill up for the past 12 years .
The only time I don,t it is when we go on a long run and the tanks are gonna refills like next day or so ,ie I,am planning to burn it up straight away .
When it’s left it’s got “ snake oil “ added .
Reckons to disperse water so I,am figuring life’s easier for the injector tips and piston crowns with regards hydrogen pitting ?? — who knows ,bit late to find a preventable problem when you have it .
It’s not a lot of € proportionally in the bigger scheme of things - running costs wise .

Q is does it work am I wasting € ??
So all these guys with bug problems are you doing anything prophylactically ?
 
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