Shelf life of avgas
 

I just bought a used 1000 litre avgas fuel trailer (the tag on it says its made by Elite Helicopters and Aviation Services in White Waltham in 2003)

It has 800 litres of 4 year old avgas in it, the trailer is a bunded stainless steel tank in very good condition however i will not be putting the fuel in the plane, so what are my options for getting rid of the old fuel , any ideas for disposal?

One option I though of is transferring it to 45 gallon drums and running it in the quads on the farm and my nephew expressed an interest in putting it in his Ford Cosworth, but not sure if it will knacker the quad and Cosi engines so want to dispose of it.

anything with spark iginition and no catalyst on the exhaust ... ;)

Would have thought disposal will cost a fortune.

Mix it around 1:3 in petrol, or 1: 8 in diesel and use it in road vehicles. Will stretch the budget for a while!

G

I'll have it for my '79 Triumph Bonneville, my 1997 Freewind, and my Honda C90! It's far better fuel than the carp sold at petrol stations, and ideal for cat-less petrol engines and especially old bikes (don't put it in a modern engine - it will kill the cat with all that lead).

Where are you based?

Supplementary question.. can I rock up at my local airfield and fill a few jerry cans with avgas for the bikes?

I may be wrong (I usually am) but would it do any harm in a C90 that can use Mogas or Avgas, If not bung it down to Kingsmuir.:ok:

Supplementary question.. can I rock up at my local airfield and fill a few jerry cans with avgas for the bikes?

If your 'local' airfield was Perranporth, then certainly! We sell AVGAS to the local vintage bike enthusiasts, no problem, we simply mark the receipt 'sold in cans' rather than an aircraft registration. I'm sure you'll find a more local airfield who will do the same.

Cheers,
TOO

Will probably depend on the size of the fuelling operation, larger suppliers will probably only sell into wing, delivery documentation stating for sale only to be used in aircraft. I'm sure there are plenty of smaller outfits who will supply as suggested above.

You want it? you got it, i,m just up the road, let me where and when you'd like it delivered.

When I used to race 125cc two stroke moto cross bike's I used avgas nearly all the time " they used to go like stink" :E

Austerwobbler

No, don't put any of it through an engine with a catalytic convertor. The lead salts will quickly coat the "cat" matrix and ruin it for good.

But for engines without one, if you mix 1 gallon of AVGAS with four gallons of unleaded, you'll have something similar to old fashioned "4 star" petrol. Works well in old engines but you'll see a grey coating inside the exhaust tail pipe, just like in the old days of leaded petrol.

Do not allow the Avgas to be run in a non aviation engine. Good chance that vehicle's systems would be damaged

I would happily run many year old Avgas in an aircraft, as long as it was free of water, and properly filtered. Avgas does not "go bad" or change characteristics the way Mogas does.

Simply, Mogas is a mixture of many different liquids, each with their own properties necessary for porper operation of the engine. When the "light ends" evaporate away, the Mogas is changed, and generally the engine won't start well.

Avgas, on the other hand is only one liquid, so as it evaporates, what is left does not changes characteristics. You know how Avgas will evaporate from your hand, leaving only a dry white residue. Mogas when it evaporates, leaves a greasy film, which is the liquid in the Mogas which does not evaporate, and that's what gums things up.

So, consider checking the condition of the Avgas, and running it in your plane, I would....

It's quite commonly used in off-road engines in UK; my own car has been run on it quite successfully a number of times, albeit diluted as above. There is no need to run it "neat" as the amount of tetra-ethyl lead it contains is quite high compared to road vehicle requirements, even in "LL" form. The fuel system does get routinely inspected for adverse effects; none noted so far after a decade or so, although I do change the rubber hoses reasonably regularly, in any case.

Fair point, well corrected.

G

It's only 4 years old. I am using older stuff than that!!

Avgas is a stabilised fuel and designed to be stored long term. There are drums of it sat all over the world that are donkeys years old. When I was out in Africa they were using stuff of greater vintage!!

It also does goes rather well in my ex MOD motorcycles!!

Piperboy
In view of the above advice, do you want a rethink?
You have a PM

Legally, I think not. Duty on AVGAS is significantly lower than duty on forecourt petrol and the fuel is supplied for aviation use only. Additional duty would need to be paid if the fuel were to be used for other purposes.

One can burn avgas in a PT6 but there is a limit on how long for, and an inspection is required afterwards - IIRC. I recall a figure of 50hrs max.

I reckon the avgas will be just fine, but as stated I would use it in one wing and not the other :)

Also, there are testing facilities available, which might be a vast factor cheaper than disposing of it, and if it tests fine then you can fly on it in the knowledge it is OK.

It's been in a bowser - the issue is that bowsers and not drums are vented - most modern vents are pressure activated.

When the stuff expands, the "high notes" evaporate first and this reduces the RVP (Reid vapour pressure) which makes the stuff less potent that the spec it came out of the refinery with.

Would I use it - yes but only after I'd sent a sample back to Grangemouth and asked them to test the RVP.

My fairly basic lab in E Africa had the kit for testing this as the temperature extremes were higher, I'd naturally have any shipment tested and compare with the refinery spec. Most of my Avgas came from Italy or from Durban. As I had no idea how long it had been in storage, a full test was standard acceptance procedure.

It will burn the exhaust valves in automotive engines if used neat and for a long time....

Stik

You could have the fuel tested. Companies such as this may help ASC Services