Petrol use-by date.

[Outdoorsman]

I have a small suit-case sized generator, which I keep ready for use during power cuts. I run it about twice a month for a few minutes each time to keep it sweet. it starts straightaway every time and I've had it for about 20 years. It has never given me any trouble and I've kept it serviced regularly by a local garden centre.
The generator runs for about 6 hours on one tank, which only holds about one pint of lead-free petrol. I keep the rest of the petrol stored in one gallon containers.
My question is: How long will the petrol in these containers keep? Will the petrol lose it's properties over time and become useless?
Many thanks for any answers.
Odm.

[Toureman]

It is reccomended that you do not store petrol for over 1 year when used in garden machinery, I usually put any petrol I have left over at the end of summer in my car and buy new petrol each start of the summer. It does deteriate over time.

[dilligaf]

I have a petrol chainsaw which I filled up with petrol stored since last year. No matter how I tried it wouldn't start. I was told that petrol stored for more than six months shouldn't be used as it absorbs moiture from the air.

Bought a gallon of fresh petrol, chainsaw started first time and, as Toureman did put the left overs into the car.

[dilligaf]

Sorry should read MOISTURE.

[alvin100]

I agree, six months is the max time you should keep fuel, It loses its octane value as it gets older.

[rugeleyboy]

i used to fix lawn mowers and 9 times out of 10 when they came in early season as a non starter we would smell the fuel and it would be stale!