Does petrol in tank go "stale" ?
Discussion
I often read that petrol at pumps can go stale if left for over a week - ie loses some of its RON value and therefore (EVO mag has mentioned this) a busy petrol station is better than a quiet one as the petrol is always fresh & being replenished.
I don't drive my 996TT much at the monent, indeed a full tank can last several weeks at the moment - will the petrol in my tank go stale ?
R.
I don't drive my 996TT much at the monent, indeed a full tank can last several weeks at the moment - will the petrol in my tank go stale ?
R.
I'm sure other far more knowledgables will be on in a moment but I thought that a RON rating was down to a certain number of hydrocarbons in the mix (sorry - total layman here), so unless these dissolve or degrade, I can't imagine much happening.
Perhaps it affects the carrying solution rather than the RON bit.
Perhaps it affects the carrying solution rather than the RON bit.
rumplestiltskin said:
I often read that petrol at pumps can go stale if left for over a week - ie loses some of its RON value and therefore (EVO mag has mentioned this) a busy petrol station is better than a quiet one as the petrol is always fresh & being replenished.
I don't drive my 996TT much at the monent, indeed a full tank can last several weeks at the moment - will the petrol in my tank go stale ?
R.
Ive been told it goes stale as well,but i think it takes a lot longer than a week. I don't drive my 996TT much at the monent, indeed a full tank can last several weeks at the moment - will the petrol in my tank go stale ?
R.
Asterix said:
I'm sure other far more knowledgables will be on in a moment but I thought that a RON rating was down to a certain number of hydrocarbons in the mix (sorry - total layman here), so unless these dissolve or degrade, I can't imagine much happening.
Perhaps it affects the carrying solution rather than the RON bit.
Perhaps it affects the carrying solution rather than the RON bit.
I think that the RON rating in part refers to the volatility of the mix. Petrols and oils are a mix of hydrocarbons of varying volatility, the higher the RON the greater proportion of more volatile substances which at any given temperature will evaporate more quickly than less volatile, heavier ones. Therefore if petrol sits in a tank for ages the more conbustible, volatile fractions will be lost by evaporation first so the actual RON value of the fuel in your tank will fall. For most I'd imagine its a fairly academic debate - I'd have thought your turbo's overall performance is more likely to be affected by, for example, ambient outside temperature. But yes, perhaps after a few months in the tank you'd be left with a less combustible solution
If it's donkeys years in the tank then yes, however I'm reliably informed that in a sealed container (ie a drum or mostly sealed petrol tank) it will last for a couple of years.
If left open to the air the lighter ends will eveporate off, and over time leave a sticky varnish like gunge behind that does your fuel system no good at all (and stinks).
In my experience I've always left the petrol in my bikes and cars tanks over the winter and have never had any trouble starting it again in the spring, and my brother regularly leaves his bike for years (because he's too lazy to go out anywhere)
There are a couple of trains of thought, one is to leave the hank half full and top up with fresh when it's ready to put back on the road, the other is to leave the tank full to have a minimum amount of ullage space for eveporation, personally I've not found any difference between the two.
Could this one is a bit of an urban myth?
Andy
If left open to the air the lighter ends will eveporate off, and over time leave a sticky varnish like gunge behind that does your fuel system no good at all (and stinks).
In my experience I've always left the petrol in my bikes and cars tanks over the winter and have never had any trouble starting it again in the spring, and my brother regularly leaves his bike for years (because he's too lazy to go out anywhere)
There are a couple of trains of thought, one is to leave the hank half full and top up with fresh when it's ready to put back on the road, the other is to leave the tank full to have a minimum amount of ullage space for eveporation, personally I've not found any difference between the two.
Could this one is a bit of an urban myth?
Andy
Short answer YES
Long answer - i'm going to refer to car storage ideas. If you are storing your car for a longer period of time than say a month then it's wise to run the engine until the fuel pump becomes noisy then kill it (so more or less dry), raise the car off the ground to prevent flat spotting, etc.
If you're storing a car for a few weeks or a month it's best to top the tank all the way to the brim - the fuel won't go off as quickly if there's less air space in the tank for vapour to build up.
So i guess if you are going through about a tankful a month then you're probably okay.
HTH
Long answer - i'm going to refer to car storage ideas. If you are storing your car for a longer period of time than say a month then it's wise to run the engine until the fuel pump becomes noisy then kill it (so more or less dry), raise the car off the ground to prevent flat spotting, etc.
If you're storing a car for a few weeks or a month it's best to top the tank all the way to the brim - the fuel won't go off as quickly if there's less air space in the tank for vapour to build up.
So i guess if you are going through about a tankful a month then you're probably okay.
HTH
Petrol does go off.
It's aparently a bigger issue on Imports where they can spend long periods standing in Japan, at auction, at docks, on boat etc and especially a problem on import bikes.
I had a Kawasaki that I took for its MOT prior to registering in this country.
When I went to collect it they hadn't done the MOT because it wouldn't start.
It had always started 1st time.
I spent hours faffing about It cracked and had a spark and fuel.
I cleaned the plugs several times as they were getting wet with fuel.
A friend in the trade said to replace all 4 plugs as the petrol seems to coat the plugs its quite common.
I was a bit suspicious as the bike would not run at all which meant all 4 plugs would have failed at the same time.
I replaced all 4 plugs and the thing started 1st time and has been fine since.
All caused by stale petrol.
It's aparently a bigger issue on Imports where they can spend long periods standing in Japan, at auction, at docks, on boat etc and especially a problem on import bikes.
I had a Kawasaki that I took for its MOT prior to registering in this country.
When I went to collect it they hadn't done the MOT because it wouldn't start.
It had always started 1st time.
I spent hours faffing about It cracked and had a spark and fuel.
I cleaned the plugs several times as they were getting wet with fuel.
A friend in the trade said to replace all 4 plugs as the petrol seems to coat the plugs its quite common.
I was a bit suspicious as the bike would not run at all which meant all 4 plugs would have failed at the same time.
I replaced all 4 plugs and the thing started 1st time and has been fine since.
All caused by stale petrol.
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