Omega Owners Forum

Chat Area => General Car Chat => Topic started by: shyboy on 02 January 2021, 09:41:21

Title: fuel degradation
Post by: shyboy on 02 January 2021, 09:41:21
What happens to cause fuel to lose its potency with age and how long does it take on average?
Title: Re: fuel degradation
Post by: Kevin Wood on 02 January 2021, 10:44:58
It absorbs moisture from the air and the more volatile fractions of the fuel can evaporate off leaving the heavier, less easily ignited parts behind.

How long it takes is another question. Depends if it's been kept in a sealed container or one that's open to the air and whether that container is full so as to exclude air or part full.
Title: Re: fuel degradation
Post by: cam.in.head on 02 January 2021, 10:45:14
i think it varies but my carlton has been off the road since early 2016 and still started up early last year but i dont think it will have any e5 in it.  beleive the e5 stuff is much worse.
Title: Re: fuel degradation
Post by: Entwood on 02 January 2021, 10:50:06
What happens to cause fuel to lose its potency with age and how long does it take on average?

Mostly caused by the "aromatics" (the more volatile elements) evaporating, so leaving behind the heavier elements that don't atomise as well, so making combustion more difficult (can often be recognised by the appearance of a "varnish" like sheen in the bottom of the tank/container from the remaining heavy elements settling)

Time is difficult to state... temperature/temperature changes/porosity of container etc etc all will have an effect.

Personally, I try to avoid petrol over 6 months old in lawnmowers/generators/strimmers etc .. and pour into the larger tank of the wife's car !! The old seems to mix with the newer quite well to avoid waste !
Title: Re: fuel degradation
Post by: TheBoy on 03 January 2021, 10:24:32
For the lawnmower, I get 2-3 years from a (metal, sealed) can.  Thats bog standard 95 unleaded from Tesco...

TBE is running on pre first lockdown supermarket petrol, with no ill effects, although whenever I drive it, the tank contents do get mixed again.