Does Diesel go off?

[dvndave]

A few months ago when it looked like fuel was going to be difficult to get I bought a 25 litre container and filled it with Tesco diesel, now I know that petrol goes "off" from bitter experience! But does diesel do the same? And no I wasn't trying to beat the price rise I am self-employed so no transport = no money!

 

[NormanB]

I am not sure about the exact shelf life of diesel, but I do know if the conditions are right that it will start growing nasties, particularly if there is a water interface (condensation inside the drum) these nasties take the form of micro biological growth (pseudomonas) and a common fungal species called cladisporium resinae (not sure if that is the correct spelling). But believe me you do not want to keep the fuel or put this fuel in your tank if this happens. Strategic oil product stocks are managed by stripping out water to remove the conditions ripe for micro biological growth and if routine tests detect the little buggers biocides are added. However biocides just kill the bugs which then form a nice smelly sludge which is beautiful filter blocking material - so this has to be removed before supply to the end user!

That aside as a refined product all fuels go through a process of trying to revert back to their natural state (that is where the black bits come from if you examine in a test tube). Again filter blocking material.

Unless you are particulary nervous about future fuel availability I would turn this stock over say every 3 months (you can always refill it).

Hope I have not frightened you - the above is just a description of what could happen.

 

[dvndave]

Thanks Norman will do as you suggest and will use it every few months, Thanks for input.

Cheers


Dave

 

[Dieselman]

I agree with Normans comments re bacterial growth but if the container is full there wont be any condensation problem. If you think growth may be a problem then add some Millers Power Plus as it has an antibac agent. Similar products are available from marine chandlers.

In reality diesel doesn't degrade and can be used many years after purchase.

 

[dvndave]

Cheers Dieselman I use Millers in the car but wouldn't have thought about putting it in the can! Will do as you suggest.

Many thanks,


Dave

 

[teky]

dsl dosnt go off its the bacterial growth that does the damage it blocks the fuel system

 

[NormanB]

dsl dosnt go off its the bacterial growth that does the damage it blocks the fuel system

First of all an apology - because I am afraid I am in danger of been seen as an argumentative bar steward here. But I feel I need to clarify a point or two!

Dave originally, effectively asked does diesel 'go off' in storage?

While I could not give a definitive answer as to safe storage times ( because there is no definitive answer - too many variables) I gave what I considered to be sound advice.

To have others then say diesel does not 'go off' sticks in my craw just a tadge - because I know it does and I understand why it does.

For those that do not know - this small and simple powerpoint may help you to begin to understand what is a complex structure and the processes involved.

Link

Dave seemed quite happy with the advice to turn the stock over - I hope that he does so.

 

[dvndave]

Hi Norman, thanks for your view I can't download the link you suggested so don't know the details but I get the impression that I have to turn the diesel over to avoid 'orrible gungy things taking over my fuel system!

Thanks for you interest I'll keep trying the link.

Cheers,

Dave

 

[tim.100]

Experience

We used to store road diesel in a 600 gal tank. We half filled the tank every couple of years, with a few gaps. One year the fuel turned clear purple. We sent a sample to BP, who said it was fine.

However, it was being used in a 1979 Golf diesel, a very simple engine....

 

[teky]

interesting thought normanb but the fact is all that happens is it sediments and its components break down so heavy parts fall to the bottom, it needs to be turned now and then and a simple pump to stir it will do that i have never heard of it actually going off, but im sure many would have started an engine that has been stood for a long time without mixing the dsl and had problems because of the water content, its all down to understanding the cracker process in oils

 

[NormanB]

interesting thought normanb but the fact is all that happens is it sediments and its components break down so heavy parts fall to the bottom, it needs to be turned now and then and a simple pump to stir it will do that i have never heard of it actually going off, but im sure many would have started an engine that has been stood for a long time without mixing the dsl and had problems because of the water content, its all down to understanding the cracker process in oils

Sorry Teky

My loose use of language

I did not physically mean turn it over I was using it in the terms of stock management - ie use and replenish.

I am not going to get into discussing the finer points of fuel storage - I am bored to death with it to be honest