What is the shelf life of petrol (gasoline) & diesel fuel? | Auto Expert John Cadogan 

I saw Mad Max, so I know it never goes off. And the Road Warrior? That was the last we ever saw of him. He lives now only in my memories.

Dear John Cadogan, While living in a somewhat damp climate here in the UK, I've noticed over the years that leaving last Autumns petrol in our mowers, does degrade by Spring time, with a minute amount of skinning in the carburettor parts. To prevent this and jets blocking, I usually add about 5mls of UCL or mineral 2stroke oil to 0.25Lts of petrol in the tank for the final last mowing. Doing this has prevented having problems in the Spring engine starts. This is of course relying upon one cleaning ones spark plug under usual maintenance. But you are absolutely correct with regard to, vehicle fuel tank sealed systems, my uncle's 1989 Nissan Micra stood unused, in a wooden garage from 2006 to 2017, with a fresh battery, it started and ran on its existing 2006 petrol. Many thanks for your welcome wealth of information. Pete

Good to have experience confirmed by knowledge. I've stored 91 unleaded for about a year in a plastic jerry can from Bunnings and upon putting it in the Prius it ran fine.

Within the first minute, he's having a go at the Irish! Braver man than I 🤣 ... #respect

This man is brilliant!

Ethanol in petrol causes older car fuel systems to rust internally and I can confirm that after draining 20 litres of petrol from my car after it stood for almost a decade it was no longer volatile , it was almost diesel like and would put the match out when trying to light it , it is a fuel injected car and actually ran on the fuel but not in a drivable way...

Pure isopropyl alcohol (IPA) makes an excellent petrol additive for dispersing separated water in a tank. Rubbing alcohol can work as long as it is 95% IPA or higher. It's what refiners use to prevent the potential separation John refers to in ethanol blends.

I own a 1976 HJ Holden V8 It retired from the road in March 2016. At that time I added fuel preserver to half a tank of 98 octain fuel & unleaded replacement additive. I have started the car once every two weeks for almost 4 years. It's still running fine & gets an oil change every 20 months. I plan to keep running the car like this until the tank is empty. I guess the tank will be empty within 6 months, then I will buy fresh fuel.

Dude....cheers from Merica! you are a Beast!!

Had a Mitsubishi Colt on a driveway that had occasional start ups to stop the engine from seizing up. The fuel was a little over 5 years old. When a friend needed the car it was driven away with no issues.

We had a 200 gallon tank of diesel that sat for around 12 years and used it just a couple months ago after adding a bottle of fuel additive from auto zone lol. Nothing broke down yet.

Wish the best to you and your country Mr. Cadogan.Thank you for your videos.My late father was an immigrant to Australia during the 50's in Adelaide.Respectfully, George from Skiathos Greece.

I miss your car reviews .

one more thing, i ran decades old diesel with no issues, ran it through a 2 micron filter added some additives no issues

As an Irishman I find this guy so funny. Class.

I'm a creationist, But not a hater. Everyone has their own point of view, and to be really honest, I do enjoy your content. Especially when the Ming Moles make an appearance, Keep up the excellent work :)

One aspect that you didn't cover is that fuel companies change the blend of hydrocarbons in their fuels as the weather changes from season to season. At least, they did when I last worked in the automotive industry some 30 years ago. No doubt cars have come a long way since then - maybe they are more forgiving now.

I’ve got a car in storage, a 2013 model, it stared and ran fine after 10 months without use.

You're awesome, John. Keep up the great work!

I used to work for a company servicing the filling stations here down under. What did I learn? There is a documented standard for fuel quality. That filling stations see Diesel stored for over six months not meet these standards and effectively not be able to be sold. So they try to turn over fuel regularly. Maybe that was our own marketing koolaid or maybe the fuel deviates from one of the less critical aspects over this time. John's advice on not using old fuel is good practise to avoid expensive injector rebuilds etc. Also E10 phase separation is taken seriously in the filling stations down under and mostly around the world. They know exactly how serious it could be and have zero tolerance for water in these E10 tanks versus less than 25mm usually allowed for unleaded and diesel before the water in the tank is pumped out. Most stations down under have automatic tank gauges that measure fuel and water height pretty much all the time. The older stations will still manually dip for water. Good work yet again on getting the facts and good common sense out there John!

When I got out in prison for 6 months I started the engine with help from another car dead battery the I had half a tank of petrol the car ran fine with the petrol that was in the car

Lawn mowers can be easily repaired and store maybe a litre of fuel at the most so you don't lose much. The more expensive mistakes come when dealing with those portable PSW inverter generators that can cost thousands. If you have a home solar and power wall setup with a back up generator it's very important to keep an eye on the gasoline sitting in the tank and in the unit itself - running the generator monthly for a few hours and then feeding it fresh fuel will make sure it stays alive when you need it. This is especially critical in climates where it does go over 30C months at a time. With the larger 400V diesel generators the issue is less common since diesel can be kept in the tanks longer with additives, flushed and in some cases even the entire tank changed. Actually it's the AdBlue/DEF in newer diesel trucks that have shelf life issues long before the diesel itself goes bad. If you do keep multiple jerry cans of the stuff you should rotate them and always go through the older fuel first. And ALWAYS have spare filters on hand if the gunk gets built up. BTW: I would have guessed TURKISH based on your name, but feel free to salute with your middle finger if that offends LOL

What a play you have with the English language. Keep it coming mate. Cheers

Even on a lawn mower, the fuel is not very exposed to air. The vent hole is small and there is only one. The partial pressure of the various compounds in the air will help to reduce the evaporation rate.

My old non injected bikes need their fuel drained out of the tank and float bowls when being stored or it evaporates off and i'm left with a light green gel that clogs everything

I don’t think I’ve ever been insulted more in one video... new sub !!

I have an ATV that I hardly ever ride, Yamaha Grizzly 125, and it sat for about two years with the same gas. It started up with the choke, and it ran with the choke on, but would not propel the ATV any movement at all, but it would run with choke and no throttle. So the fuel was too weak to run with normal jetting, but could run when extremely rich. I changed the gas out, and it runs and rides great. All our fuel has Ethanol in it, we can't get Ethanol free gas where I live. SO apparently our Ethanol gas blend, will last somewhere between 6 months to two years. But you are taking a risk if you leave it 6 months with no stabilizer, you should drain the tank and carb if you think you won't use it in a few months.

That humidity contained in the air is causing issues here in Finland during early and late winter. It is claimed that the temperature hovering around 0C with humid air makes this issue worse and causes problems for those driving daily only short distances. This can (allegedly) be easily fixed by keeping the tank almost full. So the problem in our conditions is humid conditions, not the time fuel is stored.

I have a diesel Land Cruiser with no fuel problems, but a few decades ago back on the farm up in Queensland I remember problems with cane harvesting equipment each year due to waxes in the fuel settling out in fuel tanks then clogging filters. That would be after 8 to 9 months parked up. Farm fuel has a hard life, spending time in an overhead steel tank in the sun, then gravity fed into equipment, often in dusty and dirty conditions into equipment that spends its life in sun and rain, in mud, and sometimes water, or in the center of a cloud of dust. It tests the resilience of man machine and fuel.

My 2000 Honda Civic was a hand me down left by my sister that sat for 3 years before I ever drove it. Car fired up no problem once it got jumped and it ran completely fine on that tank of gas (I’m assuming it was E10 87AKI.) Over 4 years later I still don’t have any problems.

I'm currently rotating out gas that I've had in storage since July 2019. I used sta-bil fuel stabilizer. Interesting the instructions indicate for storing fuel for 6 to 9 months. However, I have Briggs and Stratton stabilizer that indicates storing fuel up to 3 years. I have 10 , 20 liter gerry cans. When I fill them, I pour 100 fluid Oz of stabilizer In. I fill to the 20liter mark. Don't use the pump for measurement as it can very by 2 liters average, depending on temperature. I use gaff tape and mark the date, liters indicated on the pump, price and purchase station. Eventually, if the fuel isn't used, I periodically dump gerry can into my vehicle before next fill and repeat the process for marking the gerry can. This generally ensures relatively fresh fuel. I also never let my vehicle fuel tank drop below half. So I'm pouring older fuel into relatively fresh fuel and then topping that off with fuel from the pump. I have not experienced any adverse effects since I started this process In 2013. I also record my fuel purchases, mileage, price and cost. Because your filling the gerry can at the same time as you fill the vehicle, there may be a few liters discrepancy in mileage, but generally, it doesn't really affect things. That's just how I do it. I hope this was helpful to someone.

Hi from a non-Irish American in ethanol country. The neighborhood is crawling with dangerous pussy that have left foot prints on my car's hood (bonnet). I was out of country for a couple of years on short notice a few years back. I had left my 1997 Camry with less than a quarter tank in the care of a friend to be driven occasionally in my absence. Failing to drive it, the battery died and it remainded in place for the entire time. I had heard all the horror stories of bad petrol (gas) and watched videos about draining the tank, cleaning injectors, doing rain dances, etc. When I returned I clutched worry beads as I replaced the battery. The car started like I had just driven it yesterday. I filled the car up with petrol (gas) and drove on I like I was never gone.

Unleaded petrol does go off, I have been working on a late model Ferrari that has sat, unused, for over 2 years. It has 2 seized fuel pumps, gummed up injectors and fuel that has turned to varnish in the whole fuel system. The smell that is put off by the fuel is acrid and does not smell like anything resembling a petroleum product... (think cat piss).

Wow... AMAZING PUNS, wordplay... Earned my sub

Had a 1943 Jeep with a Holden engine. Left it sit for 20 years then hand-balled it to a mechanic mate who tweaked a few things and had it running on 20 year old fuel. He was gobsmacked! At that stage I recall only ever filling up at Mobil.

Does anyone have a clue is it a smart thing to buy a 6 year old diesel car (I am stuck to buy because it is rare car with low millage) from a seaman which was driven periodically. The car was not turned on for app 4 months, 2 times per year so the diesel + 5-7% of bio component could stick and partially clogged the fuel system... Any thoughts?

Which one of Yuz came up with the term 'Prime Mincer' sheer genius seriously. I t has to be in line for a Golden Galah, Mick Dundee bush poetry award.

Ya shoulda told im John that da petrol goes green and thats where the 4 leaf clovers come from. Seriously you blew away lots of myths in my head. Thanks.

John, I believe the most dangerous creature in the Rip Off Republic is the Bee not just any Bee a small Pussy Bee in comparison to most other Bees. If not the most dangerous it is certainly the one they are most afraid of. I happened to got to Tayto theme park in Dublin a few years ago on one of the three or four good days the country gets all year and witness a spectacular sight. A sight of men, women and children alike screaming in terror if one of these Pussy Bees happened to buzz around them.

About modern diesel; common rail engine is gonna shit him self after 2 years not running at all. We bought MAN TGA 430 truck which was 4 years old at the moment with 300 000 km on odometer. Both of those numbers say almost brand new truck. But there is a catch truck was parked for 2-2,5 years. Obviously we done service regular ASAP but error messages kept coming. Brakes don't work, engine malfunction, shifting gears malfunction... it was pain in the ass sorting all those things. New generation trucks were designed to be driving all the time and parking then for extending period of time is worse then driving them 10 hours every day.

My 2 stroke motorcycle sat for 7 years unused with half a tank of fuel in it, and it started up on the 4th kick. Ran kind of shitty but I ran out the fuel and added supreme to the regular fuel and it ran normally. The bike was parked in the shade so not in sunlight under the porch. Steel tank and a non breathing cap Never added fuel extender or anything. Usually the bike is parked over the snowy winters and is used every year. But didn't for awhile as I had a different bike so it just sat. That would be unleaded fuel.

the solution is simple, always put that old fuel that has been laying around forever, unleaded, e10, two stroke, whatever - into the missus' car!

Excellent information, thankyou John. 👌🏻👍🏻

I'm guessing our Irish mate was asking about fuel going off in carbys of older cars. the kind that might sit in a shed during a harsh Irish winter.

Thanks for all the theory. Here's a fact. Old unleaded petrol stinks worse than shellac and gums up your filters etc. This is well known from personal experience and the experience of people restoring old cars.

Do those 'fuel stabilizers' work or are they just snake-oil...

I watched this because I bought a little petrol generator and it's unlikely to be run unless there is a power cut. I'll add a bit of fresh petrol before I use after reading the comments below.

Nice one geezer, you just explained why cleetus drained the ethanol and ran standard petrol thru his burnout car before sending it from the US to oz for summernats 2020

John, is it better to store the car with the fuel tank full or nearly empty?

Since Australian fuel is imported the BP 3 months shelf life for Australia because of the heat here would theoretically be reduced to 10 weeks due the time taken to sea freight the fuel to Australia.

"Perhaps, the long awaited sequel to the great movie "Snatch" - I lost it there :))))))))))))))))))))))

I read diesel stored correctly for military use is good for ten years. The storage medium can affect the storage life of diesel eg. a copper storage tank (not recommended) will render the stored life to two years because of a reaction between diesel and copper. There has been a lot of research on fuel storage and storage vessels.

Bloody hell, would you consider posting an executive summary video?

Thank you for explaining what the strange fiery ball in the sky is. It has been months since I last saw it. The sky has been leaking for what seems like the last four months.

You my friend are bloody hilarious 🤣 Nice one, and good info

Ive been running an unregistered car thats been sitting for 26months with the same fuel in it for the same time and it runs fine.

Had several project cars on jacks for sometimes the better part of a year. All were sealed fuel systems (OBDII era, sealed fuel filler caps, fuel injection, pressurized systems). All had some difficulty starting, but after a few minutes of smoke and rough running, they all calmed right down. Outdoor power equipment with open fuel tanks is definitely a bit different. Based on a previous video on this channel, I am foregoing the Sta-Bil this winter, just to see what will happen in the spring. Wish me luck.

I've had petrol in a steel jerrycan, go cloudy. It was no more than 6 months old and stored in the side of the shed that is shaded by trees. I now always use a marine fuel stabiliser if I'm not going to be using that fuel straight away.

When I had a (leaded) petrol generator. Which was not a sealed system. If left for a long period without being used. The fuel would turn to jelly in the bottom of the carburettor. Stopping the engine by turning the fuel off helped to prevent this.

I came here because I've been wondering if the plastic gas cans that I've been storing gasoline in for the last 3-4 years is still good. I've been storing for emergency use for my portable generator.

The gas in Europe must be fantastic since it never goes bad.

My vehicles get stored alot, so I use Sta-bil to keep moisture in check. As for diesel fuel you'd best use an algacide if sitting, especially in high heat and humidity.

IF JOHN RUNS FOR AUSTRALIAN PRIME MINISTER I WOULD LOVE TO SEE THE NATIONAL DEBATE WITH JOHN CADOGAN AND SCOTT MORRISON DEBATING AND JOHN SAYS WE WILL MAKE AUSTRALIA LESS SHIT I WOULD DIE TO SEE THAT ON TV!

Mate your a gun with words. Very entertaining.

If your storing a car...Fill your tank with premium. Start your car once a week or so and let it run for 20-30 mins. Top off with fresh fuel every month or so... keeps your fuel fresh, battery from dying and keeps your engine from corroding and seizing up.

Dearest mr. cadogan, doesn't the petrol fumes displace air in the tank? What happens to a tank of petrol, say 3/4 tank, drive whatever, shut off. Is the volitility of gas going to provide a pressure against which air cannot compete. Bottom line Since petrol is so very volatile, don't the fumes displace the air in an auto gas tank?? Or...

I have a 1969 HK GTS Monaro that has sat since 1990 in doors out or the weather with fuel in it which I didn't give much thought to and I started to smell stale fuel from time-to-time and unfortunately found it has rusted through the tank and those big long range Monaro tanks I have seen go for 3 to 5 thousand dollars. So I made sure to empty the tanks on some other cars I am storing and just hook up a 10Lt axillary tank to the engine if I want to give them a run.

More importantly, how many caps do you possess?

"Wildlife that kills." You know what St Patrick said to the snakes when he drove them out? "Are you alright in the back there, lads?"

That dangerous animals in ireland forgot Liam Neeson, and quite a few priests really.

I keep a Jerry can in my truck because I do roadside assistance as a hobby. That can Will plump up big as a pumpkin in the summer if I don't burp it and in the winter it shrinks

Alcohol isnt to be used in Aircraft either, for similar reasons and electrolysis between dissimilar metals such as brass plumbing fittings and aluminium tanks as well..

Had a back up power plant ( diesel ) in 2001 that that not been run- (USA) 10,000 gal of fuel- changed batteries - started up and ran fine for 6 hours 2018- was set up to run the fire systems if power failed - worked just fine- no additives for 10 of the 18 years

That Irish Felis catus sent shivers down my spine.. Never visiting yeu Ireland!!

I was just asking this question yesterday. Thank you!

So you're saying I boil my stored diesel due to bacteria formation?

If you haven't added gas after one year, my Chevy Volt plug-in hybrid will force you into ICE mode every time you drive it until the entire tank is burned off. It will also force you to run the ICE for a few minutes every six weeks or so, if you haven't otherwise burned gas.

What if the gasoline fuel tank in my car is almost entirely empty, and I don't use the car for two weeks in the summer. Wouldn't moisture and repeated condensation by the warming-up in the sun and cooling off in the evening dilute the small amount of Gasoline and make it unusable as fuel and possibly create damage to the engine or elsewhere?

does this apply to supermarket fuels? I'm told they buy stored fuel wholesale and is inferior and damaging to the engine vs branded fuels like BP, Shell, etc.?

What are you talking about, centrelink people can't afford 4WD utes

Is it ethanol-o'clock yet? 😎🤣

Don't know if You already have, but You should do a video on what the F is " Dealer Fees" or "Registration" or even "On the road Costs" that ALL car dealers NOW seem to have when buying any vehicle. Its very expensive and one of those unexplained mysteries?

Ok. In a Non-sealed tank (older car/bike/mower/chainsaw etc) the fuel looses its active ingredients (Not sure what else to call it) due to evaporation. The characteristic 'Fouled plugs' is the result and the engine is difficult to start or keep running. Ive diagnosed many older cars as they come in running 'Rich and fouling the plugs'. Not sure exactly what compo ent of the fuel evaporates but as soon as 4 weeks in a tank. Its VERY common on seldom driven vehicles and has been happening for over 10 years. Cast Iron heads seem to exaggerate the issue

Not sure if this is relevant to this video, but does it matter if you go to an old petrol station with metal tanks as to a brand new servo with polyurethane bladders or whatever they use now. I only ask this cause iv seen a few servos decommissioned lately and when they pull the tanks out of the ground they are covered in so much rust. Ever since iv only go to new servos now.

John what happened to your review of the Beemer you were test driving a few weeks back ? Not that any of us could buy such a conveyance , but it would be good to see your review out of curiosity ... you mentioned you were driving it for review so surely we could expect one ? Was it good or disappointing?

Got scared by a God when you were a little child eh John? Sometimes the same happens with Circus Clowns, I still find them frightening and avoid them at all times, even in my old age.

John - from this Canadian,you are the best on auto info.

How does one submit a request for a topic to be covered by our fine Prime Minsa?

Glad you did a video on fuel sitting for long periods 👍

LOL I'm one of the Dog Crap Dumb Creationist, but not an A-hole. Nice to know your looking out for us Creationist's too! "Do unto others as you would have them do unto you". Luke Chapter 6 verses 31 through 36. So I still gave you a Thumbs up for the knowledge. Best Wishes & Blessings. Keith Noneya

Facts and figures are all great and that, But I fix fuel systems all the time all year round from bad petrol going off. Can be very expensive for my clients sometimes too, depending on the level of degradation and how far I have to go to clean the systems. I see petrol all the time that looks like piss and stinks foul and lingers around the shop for ages and sometimes wont even burn if you light it with naked flame so no chance at all that Ubute electronics will get the engine running. It does happen and happens often. That putrid petrol leftovers is the best ever chemical I have ever come across for killing ant nests and double G weeds if you can stomach the stench.

In Masscahusetts there is no place you can even buy real non ethanol gas.

What a great subject John. I own half a dozen ICEs (not including the fire pump) that I'm always worried about... especially my RXT300 seadoo that requires high octane fuel...

But, but here in the States they are wasting our corn squeezings (should be over ice) and it is terrible on the old classics... Awesome topic, again.

LOL ... nice vid! Informative and funny! 😊👍

I have been in the habit of releasing the built up pressure in my 20 Lt plastic jerry cans when they get hot and start to expand. From your talk, I will assume, I may be degrading the contents by doing so . Correct?

Please do a follow-up on the BS fuel 'stabilisers' (for winter storage).

Not likely to be 30 lt of "air" either. I would suggest 30 lt of fuel vapour.

Do fuel stabil-izers assist in mitigating the issue of fuel stabil-ity or are they in the realm of engine treatments?

So I just found 1000litres of fuel in what I thought was an empty tank. My late husband was a bit of a hoarder and this tank was in the bush hiding. I’m moving so am cleaning up and that’s when my friend figured out it was full. So it’s in an actual diesel tank labeled diesel, and we pumped some through the filter I have on my fancy tidy tank. The 15 year old-ish is yellow and doesn’t really smell at all. What do I do with it?