life of fuel

[GeekOKent]

Hi,

How long can diesel be stored before it starts degrading ? I guess as long as the container is stored completely full, and is made of a material that itself wont react with diesel then there should be no real shelf life - it should just last forever ? the biggest problem being moisture / water. However, BP and Shell ( and others.. ) seem to say that diesel starts degrading after a few months, and is unlikely to function as fuel oil after some period of time.

I know of atleast a couple of vehicles that dont get fuel'd often - a friend of mine who lives in Finchley will often only get diesel in his car ( its a vw polo ) maybe 2 times in a year! I dont think we could really consider the fuel tank in a car to be a closed system. And afaik, he's never had a problem.

Petrol is meant to break down even faster! 40 to 60 days seems to be the life span recommended there - but again I know of many cars that likely go much longer sometimes between fuel runs. One of the guys I work with is helping bring up a new team in Warsaw, and has his car in the UK parked up for 3 to 5 months at a time, and I dont recall him ever coming back with a 'hey, the petrol turned into water' problem ( he's driving a ford modeo 1.8 zetec ).

The other thing is that when fuel does break down - is it just a case of more gunk in the filters, while it does still burn ( maybe not as efficiently ) - or is it a case of actually having to flush the system out.

regards

 

[Chas]

No problem with life of diesel in my 80, it drinks it too quick.

 

[Towpack]

I think modern fuels are more stable than they used to be. My road bike can go a couple of months in Winter without a run and still starts OK but I always try and leave it with close to a full tank. I'd much rather leave it stood idle than starting it up maybe once a week/fortnight and letting it idle for a while. Bad idea IMO. Back in the early 90's my road bike at the time (FZR1000) was laid up from Nov to Feb the following year with maybe a 1/4 full tank and not only was it reluctant to start but also smoked and pinked quite badly when first ridden. A full tank of fresh fuel cleared it up almost immediately. There are fuel stabilisers available for long term lay ups but I've never used them. If anything I would say diesel has (or used to have) a longer 'shelf' life than petrol being less volatile but with bio diesel mixes maybe that is an issue?

 

[StarCruiser]

Unleaded degrades quite quickly. You can actually smell it when it's old. It'll last longer in a closed fuel can but things like mowers often won't start if left with fuel in over winter. If itvevaporates completely it leaves residue that gums up fine holes in carbs for instance.

Diesel on the other hand will last far longer, many years I believe as long as it doesn't get waterlogged or get diesel bug, which I don't know much about. If you think about it, there's thousands of standby generators that have fuel tanks sitting unused for long periods of time. There are companies however that specialise in fuel conditioning or 'polishing' which removes contaminants. You can also get stuff to guard against/kill diesel bug.

https://en.m.wikipedia.org/wiki/Microbial_contamination_of_diesel_fuel

 

[Chris]

My silver 80 stood in a garden for 8 years with the same fuel in the tank and still started first touch of the key. It smelled very different to modern diesel, was a different colour too. This was in the good old days before they started making fuel that was squirrel friendly. I have a 100 litres in Jerries stored away with my other apocalypse gear. Hope that doesn't let me down when the zombies are chasing me.

 

[froggy Steve]

lol, I was walking with the dogs this morning in the woods, and suddenly thought I have 10 galls of deisel in Jerry's on my trailer - I better use it before it goes off, but at 8 years I think Im ight be OK

 

[ratrace]

the fuel in the Landrover is still good from the last trip to Romania in 2015 as i not allow to play with it. Wife orders. I do start it up every week so all good so far

 

[clivehorridge]

I've got a petrol (unleaded) generator and that's been standing for 2 years.

Tomorrow I'm going to fire it up to be sure the tree doesn't go dark if we have a power cut over the holiday

The tank was half-full (a pessimist may say half-empty?) when I last ran it and my stock of 20lt is kept in a sealed Jerry can. That's 2 years old as well, so I might find out if there's been any deterioration.

Hope not.

 

[GeekOKent]

60days, is what BP says is the life of their petrol. So be interesting to find out.

 

[clivehorridge]

60days, is what BP says is the life of their petrol. So be interesting to find out.

Ah, but this is RP (Rompetrol) with added Palincă most likely

 

[StarCruiser]

Ah, but this is RP (Rompetrol) with added Palincă most likely

Flippin' Nora Clive, you know how to live dangerously!! Better run a heater off it just so it doesn't over speed and blow all your Christmas lights!!

 

[AndycruiserguyLomas]

My silver 80 stood in a garden for 8 years with the same fuel in the tank and still started first touch of the key. It smelled very different to modern diesel, was a different colour too. This was in the good old days before they started making fuel that was squirrel friendly. I have a 100 litres in Jerries stored away with my other apocalypse gear. Hope that doesn't let me down when the zombies are chasing me.

Like Chris's 80 my GS was stood for 10 years outside in a farmyard (it was laid up in 2001) It probably half a tank of fuel in it. When connected up to batteries it started instantly (like they do) and ticked over like it should.
I never drained this fuel, just used it and it was fine until it I filled it up with fresh and that was fine too.
The V6 Collie on the other hand had 5 year old petrol in it which, while the engine would run on it, smelt disgusting, was dark brown and decidedly thicker than its intended form. This was drained and the tank steamed to remove all traces and the fuel lines blown back. Its still smelled of it for a while after I started using it but its gone now.
Maybe the fuel of 15 years ago lasted better than the modern stuff, that said there have been times in my ownership of the Blackbird where its been stood with petrol in up to a year and its never been an issue.

 

[Shayne]

I have seen petrol gone crusty many a time but never diesel , that said it must be approaching 20 years since i last salvaged anything and with all new cars being digital i suppose fuel has been improved like everything else to offer the cheapest possible quality .

 

[nathanrobo]

The biggest issue in modern diesel is the up to 7% biodiesel. Both dyno and bio diesel are prone to diesel bug (bacteria that forms) and oxidisation, but bio will oxidise more rapidly and is more prone to bacteria. There are additives that can be used to lengthen life and oxidisation stabilisers. There's a firm called Chemiphase that manufacture this stuff and it's added at a ratio of a few parts per million.

There are other solutions to combat bug where the fuel is passed through an electromagnet (I think) and this renders the bacteria inactive the individual spores do not cling together - they can then pass through the filter and burn.

When folk get away with very old fuel, you can't guarantee that a problem isn't being stored up for the future. For example the fuel filter could be catching bacteria, maybe slowing down the flow rate, but not to the point that you'd notice. If unchanged the filter can become filled, at this point pressure can allow the filter to become 'punched through'. The next hurdle is what happens in the IP. There's a fine finger strainer in the IP, so this will prevent some of the contamination getting into the pump, but again slowing the flow rate. Eventually this stuff can block things up in the injector pump and the injector nozzles. The thing is, when somebody has issues with the IP or injectors, it's difficult to definitively figure out what the route cause would be.

Better to be safe than pay though (I speak from experience)

 

[GeekOKent]

Great experience here, as I thought there would be. The background for my question was - with the stored-for-rainy day fuel, in jerrycans or otherwise, should we be cycling it every few months.

 

[Towpack]

stored-for-rainy day fuel

Have you got wind of more fuel delivery strikes or something??

 

[nathanrobo]

If you are cycling fuel every few months you should be okay. If you are really serious, you could use a storage tank and dispense via a filtertechnik polishing pot - which would be fairly inexpensive.

Also keen to know more about the "rainy day scenario"

 

[clivehorridge]

As an aside, the genuine fired up on the third pull, and ten as sweetly as I'd did with fresh petrol in it!

I guess it's a very low spec engine, so pretty tolerant of off spec fuel.

Anyway we're good for a blackout, it cranks out almost 8 kW so it's enough to run the house without any compromises.

Merry Christmas all!

 

[Towpack]

I guess it's a very low spec engine, so pretty tolerant of off spec fuel.

I think you've hit the nail on the head there clive. When you're designing an engine to go in a vehicle that will go just about anywhere and be sold worldwide then it must be capable of running on poor quality fuel. Maybe a lumbering old 1H series LC motor isn't too bothered by poor/old/ low spec diesel that would make a modern high pressure common rail electronic power plant throw up in disgust!

and to all

 

[GeekOKent]

Have you got wind of more fuel delivery strikes or something??

not really.

But i do have 40ltrs in 2 cans that I had carried out with us on the last trip to the french Atlantic coast. Been sitting in the garage now for 3 months. Wasent going to use it and just it drive or with it next time. Also the 105 has the OE sub tank that i don't usually use from all the time.

It's all diesel though. The only petrol car in the family gets used daily pretty much. And i wouldn't want to store petrol at home anyway.

Regards