Diesel mystery

[Jo Green]

I have a problem which i can't solve. Maybe someone can shed some light....

 

I filled my tank with diesel a few weeks ago and have not used much fuel since then. A couple of weeks ago I came back to the boat to find a 20l can with a tiny bit of red diesel in the bottom, on the roof of my boat. The can wasn't mine and I thought it was strange but I didn't follow it up in any way.

 

I had my engine running just now and it started chugging and then cut out. (It's a year old only). I wonder if someone stole my diesel but when I measure the level it says 25 gallons are in the tank. Would potential fuel thieves have added water to the tank? Or is it more likely to be a filter issue?

 

Any thoughts appreciated.

 

 

Thanks

[Nightwatch]

Sounds like someone has taken some or all your diesel. Are you near a water tap?

[Nickhlx]

Suck out a pipeful from near the bottom of the tank and put it in a e.g. an empty 2L coke bottle.

 

Have a look and see if there are two layers - the bottom layer will be water.

 

If not suck another pipeful out from the top of the tank (or a known-good diesel supply) and put this in the same coke bottle, and have another look.

 

Regrettably I would be leaning towards someone nicking your diesel, especially if there is not a locking fuel cap

 

Nick

[MtB]

I have a problem which i can't solve. Maybe someone can shed some light....

 

I filled my tank with diesel a few weeks ago and have not used much fuel since then. A couple of weeks ago I came back to the boat to find a 20l can with a tiny bit of red diesel in the bottom, on the roof of my boat. The can wasn't mine and I thought it was strange but I didn't follow it up in any way.

 

I had my engine running just now and it started chugging and then cut out. (It's a year old only). I wonder if someone stole my diesel but when I measure the level it says 25 gallons are in the tank. Would potential fuel thieves have added water to the tank? Or is it more likely to be a filter issue?

 

Any thoughts appreciated.

 

 

Thanks

 

 

Oh dear that's unfortunate.

 

It sounds to me like water in the diesel too, or possibly diesel bug contamination that has stopped the engine.

 

I doubt the can on the roof is relevant, although it seems quite a coincidence. More likely an attempted fuel theft that got interrupted...

[Ray T]

Have you a locking fuel cap? If not get one sharpish.

 

Get hold of a Pela type pump and pump some fuel from the top, middle and bottom of your tank into glass jars or milk bottles. If it all looks the pink I would suggest your fuel hasn't been tampered with.

 

If it is different colours I would suggest either you have been a victim of theft or have the diesel bug. I would then seek proffesional help to get your fuel system cleaned.

 

e.g. https://www.crownoilenvironmental.co.uk/fuel-polishing/?utm_source=bing&utm_medium=cpc&utm_campaign=Environmental%20Services-%20Search&utm_term=diesel%20fuel%20cleaning&utm_content=Fuel%20Cleaning

Edited September 3, 2016 by Ray T

[Jo Green]

Thanks. So is it an established method of stealing diesel- to add water to the tank?

[MtB]

Sounds like someone has taken some or all your diesel. Are you near a water tap?

 

 

But the OP says dipping the tank reveals 25 gallons of fuel...

 

I suppose someone nicking 20 litres might pour 20 litres of water in to disguise the theft, but what would be the point? a fair bit of effort and why they care about the theft being spotted?

Thanks. So is it an established method of stealing diesel- to add water to the tank?

 

 

No, it isn't.

[valrene9600]

How are you measuring it?

Did you have a lock on the filler cap?

I suggest you suck some of the contents from bottom of tank before you do anything. You are looking for water. If no sign of water then sounds like a straight forward theft that has left your fuel level below the take off pipe feeding the engine and this has caused the chugging.

After sorting this out be aware the thieves will return having got away with it once. Get some good security on the cap.

Thanks. So is it an established method of stealing diesel- to add water to the tank?

I would have thought once they had your diesel they would not hang around to put water in the tank because you are soon going to find out when it chugs. They would use the time to escape.

[NMEA]

Spark the heater up Jo, the dip tube is a above the engine pick up, if the heater runs OK for ten or fifteen minutes then it is not a fuel issue, if the MV protests then it is.

[MtB]

Sounds more to me like sabotage. Someone used the can to pour 20 litres of water into your tank. Is there anyone upset with you badly enough to do something like this?

 

TIme to crack an injector pipe and see if diesel or water comes out I suggest.

[Paul C]

I have a problem which i can't solve. Maybe someone can shed some light....

 

I filled my tank with diesel a few weeks ago and have not used much fuel since then. A couple of weeks ago I came back to the boat to find a 20l can with a tiny bit of red diesel in the bottom, on the roof of my boat. The can wasn't mine and I thought it was strange but I didn't follow it up in any way.

 

I had my engine running just now and it started chugging and then cut out. (It's a year old only). I wonder if someone stole my diesel but when I measure the level it says 25 gallons are in the tank. Would potential fuel thieves have added water to the tank? Or is it more likely to be a filter issue?

 

Any thoughts appreciated.

 

 

Thanks

 

Is 25 gallons full, half full, third full???????

[MtB]

 

Is 25 gallons full, half full, third full???????

 

25 gallons is about 110 litres, a bit on the small side for a diesel tank but quite possibly full. And as you highlight, the OP said they filled the tank shortly before so probably not space for adding 20 litres of water without removing a similar amount of diesel first. The whole thing is rather weird actually.

[Paul C]

My thoughts are that to siphon off the diesel, the container would need to be at/near the waterline to do so, depending on the detail shape of the boat's hull and diesel tank location etc. So its possible that some water entered the tank if the siphoning went wrong (possibly at night) and put some canal water into the tank. Most boats have an agglomorator, I'd be looking at this and the filter first.

[Keeping Up]

During the winter before last someone stole half a tank of diesel (from our full tank) and left it contaminated with water and bug, despite us having a locking cap which they apparently picked, so that the engine kept cutting out. It took us a great deal of effort to get rid of the bug, which was so bad that the usual methods (fuel polishing, biocide, etc) all failed until we had to have the tank steam-cleaned to kill it.

 

Luckily our insurers took the view that as it was the result of a theft, they would pay for the treatment that we had (which cost over £1500 in all)

[MtB]

My thoughts are that to siphon off the diesel, the container would need to be at/near the waterline to do so, depending on the detail shape of the boat's hull and diesel tank location etc. So its possible that some water entered the tank if the siphoning went wrong (possibly at night) and put some canal water into the tank. Most boats have an agglomorator, I'd be looking at this and the filter first.

 

 

Whatever has happened it doesn't seem like an ordinary diesel theft.

 

To syphon canal water into the tank by accident whilst nicking diesel as you suspect seems incredibly unlikely. Canal water would need to have been accidentally syphoned into a can which can't happen without the can being lower than canal water level.

 

YThe can left on the roof seems equally odd as 20L jerry cans cost £30-ish so unlikely to be left behind casually. But that's what we have. On balance it seems more likely that as the can was empty and left behind, a diesel theft was planned but interrupted. The engine stopping seems more likely to be a coincidence and caused by diesel bug.

During the winter before last someone stole half a tank of diesel (from our full tank) and left it contaminated with water and bug, despite us having a locking cap which they apparently picked, so that the engine kept cutting out. It took us a great deal of effort to get rid of the bug, which was so bad that the usual methods (fuel polishing, biocide, etc) all failed until we had to have the tank steam-cleaned to kill it.

 

Luckily our insurers took the view that as it was the result of a theft, they would pay for the treatment that we had (which cost over £1500 in all)

 

 

Any idea how and/or why the water came to be introduced during your diesel theft?

[Paul C]

Unless there's a psychic on the forum you're not going to get answers to some of the questions you've asked. However, others can probably help on the non-running issue. For example, how do you know you've not been sold a dodgy batch of diesel at the last fillup?

[Keeping Up]

Any idea how and/or why the water came to be introduced during your diesel theft?

Yes, rather boringly they couldn't be bothered to tighten the filler cap down properly afterwards so it was just rainwater.

[LEO]

Hi,

 

Note you are in London, presumably you purchased the fuel from a fuel boat? - there seems to be a fair number of fuel thefts in the area, is it possible that someone follows the fuel boats around and takes advantage of the delivery system?.

 

Checked the filters? could be that you have just got problems with the fuel bug?.........

 

A locking fuel cap is something which should be fitted..

 

Good Luck, hope you sort it out.

 

L

[widebeamboy]

how did you fill up? Marina, fuel boat or the services of a man with cans delivering by road? Are you cruising or in a marina most of the time?

 

Is it possible that the can on the roof was left by the the man delivering by road (if that was the method you used). I use a man with a van delivering by can and can imagine it would be easy for him to forget a can especially if he is doing two or three cans on his trolley each trip or a couple of boats in the location he is visting.

[Carrie]

Sorry about your problem Jo. I have the same mystery today...

Having left my boat for a few months at Market Harborough basin (seems fairly secure & overlooked) while I went abroad, I'm off travelling again. I knew I had plenty of diesel but called into a boatyard tiday to top up - only to find my tank was almost empty :-(

Either it's been nicked or i've got a serious leak.

[Nickhlx]

If a serious leak I feel sure you or someone would notice pretty quickly !

 

Nick

[MtB]

If a serious leak I feel sure you or someone would notice pretty quickly !

 

Nick

 

 

Well yes, if its a leak out of the boat into the canal. A tankful of diesel (say 100 litres) will create a stinking film on the water capable of covering several square miles of water surface area. The world and his dog will have noticed and have been on the case long ago.

 

If the leak is into the inside of the boat though, there will just be 3" of diesel in the bottom of the engine bay and an unusually strong scent of diesel wafting around. A quick check in the engine bilge will reveal if all the missing diesel is there instead of in the tank.

 

If the engine bilge is empty then yes the OP has had it nicked. There is no other explanation I can think of.

Edited September 6, 2016 by Mike the Boilerman

[cuthound]

On my last hire holiday I ever had (1991) we started from Penkridge. Next day we stopped at Coven for lunch.

 

It was a really hot day and when we came back to the boat, the rear deck and a large patch of canal were covered in a rainbow film.

 

My first thought was that some barsteward had used the stern of my boat to dump his old engine oil. Then I had a closer look and realised that it was diesel which must have expanded in the heat and escaped from the tank via the vent.

 

It could only have been a small amount, maybe a tablespoon or two, because I later found out that one litre of diesel spilt on water will spread to the area of a football pitch.

 

So if your tank is leaking significantly to the canal you will be followed everywhere by a rainbow coloured patch of diesel.

[Nickhlx]

Quite !

 

Nick

[Carrie]

Ok thanks - a slick would definitely have been noticed in Market Harborough basin. And I can't see or smell diesel in the bilges.. I wonder if it got nicked when I left it for a week near Whilton. Hey ho. I'd rather that than have a leak. I'm belatedly getting a lock on the diesel cap. I know - Horse & stable-door!