How long does petrol last

[pena]

Left my car park (due to other problems)...
Anyway just started her up, but running very erraticlly, with the occasional slatter and back-fire...

The tank was on low (just before the red), and the cars been parked for 2 weeks...

IS THE FUEL GONE OFF?

>>> Edited by pena on Friday 5th December 19:22

[No 1]

I'm no petrol technician, but it's doubtful. I've left cars for months at a time before now with no problems. Try cleaning your stepper motor. (I don't know why, but I've seen the comment so many times, and I thought I'd get in there before anyone else pipes up with it)

[pena]

Hope thats the fault, right am gonna try and see if i can find out where it is for all the OTHER stepper motor posts...

Cheers

>> Edited by pena on Friday 5th December 19:40

[moschops_72]

pena said:

The tank was on low (just before the red), and the cars been parked for 2 weeks...

I was EXTREMELY low on fuel... even thought it was showing over 1/4 of a tank left...

The moral of this little snippet of a story.... NEVER try to drive over 200 miles on a tank, better still, don't let the needle on the fuel gauge drop below 1/3.

Jeff

[haggishead]

Petrol DOES go off, don't know why but it loses its volatility - but it takes ages, a lot longer than two weeks...

[pena]

Just went back to clean the starter motor, but before I did I thought I try and start the car again....

The fuel pump primes, but the engine is just turning over and over, but refusing to start...

This is really starting to bug me now.

[Edt]

fuel lasts for a long time !

[stainless_steve]

No more than an hour in my car

[simpo two]

pena said:

The fuel pump primes, but the engine is just turning over and over, but refusing to start... This is really starting to bug me now.

Maybe no petrol?

[julianhj]

I've had this happen... when I ran out of fuel (blimmin' random fuel guages!).

Worth putiting a few more litres of fuel in to try and cure, if you are currently low.

[Derek Smith]

If you have let the fuel run really low you may well have picked up some of the gunge that lurks at the bottom of tanks of your vintage. I know it's a bit late now, but you should never run dry. Filters block up as they are not intended to stop loads of muck, just bits and pieces.

[jeff m]

The problem with petrol staying in a car for an extended period is not that it will not be "as good" as it was when new but that aging petrol will leave a "varnish" deposit on everything it is contact with.

The use of a fuel stabeliser will prevent the deteriation.

Jeff

[jmorgan]

Had a recent problem where I flooded the engine. Had spark, fuel etc but wouldn't go bang. I dried the plugs and still no joy. Got it going by drying the plugs, heating them on the house rads for a while and shove them in still hot and it worked. Apparantly the flooding had left a lot of deposits on the plugs, even though there was a spark, but under load the spark found the deposits rather than the electrode tip.

I checked for fuel and spark, both there. Didn't reckon on the fouling. This was after a 3 week gap in use.

[pena]

jmorgan I think I might have the same problem you have. The flat of all this was that the electric had played up (see other post), leaving the fuel pump priming for a few days, when I started the engine the first time, it came on straight away, but would not hold its idle, then it cut out. When I tried to restart it, all it does is just turn over....

[bassfiend]

haggishead said:

Petrol DOES go off, don't know why but it loses its volatility - but it takes ages, a lot longer than two weeks...

My boss worked out the other week that over the last year he's done 140miles in his 355 and hasn't actually filled up the car since its last service.

Now - apart from being a waste of a very nice machine I had assumed that the fuel would have "gone off" but no - apparently it started first time and ran fine.

Phil

[pena]

Thanks guys...
Its not the petrol...

The car now starts and runs, but very lumpy...
Will have a better look @ it in the morning...

Feels like a broked spark plug lead or something!

[snorky]

volatility of petrol is measured with something called RVP ( Reid's Vapour pressure ) ( you home chemists can try this by connecting a pressure gauge to a bottle of petrol and measuring the pressure given off). As the fuel tank is essentially sealed , apart from the route to the carbon can in the wing - much of the VOCs (Volatile Organic Content ie: benzine , toluene ) will be retained so would take AGES to "go off" if at all. Plus if the tank is full of vapour, which it wil be, this displaces the air which is a contributary factor in oxidising the petrol - I thank you.... buy "JET" petrol - you're helping to pay the bills on my Chim - Thanks !

edited to add: in the winter we add some more VOCs to the blend to help starting when it's cold as the petrol is not "evaporating" as quickly as it does when it's red hot in the summer ( yeah right...arf ) but petrol is not like Pepsi, it doesn't run out of "fizz" - it just fizzes easier when it's warm...if you see what I mean - hope you got that, there will be a test later..

>> Edited by snorky on Sunday 7th December 12:33

[GreenV8S]

If you're leaving the car for any length of time, its worth making sure the tank is brim full. The bigger the air cavity the more condensation there will be in the tank, this will accumulate to give you water in the fuel. This can cause all sorts of running problems and you may need to go through several tanks of fuel before you completely flush it out.

[campbell]

You ask how long dose fuel last, well not dam long enough when i go out for a spin but i luv it.
At least the rev counter just faster than the fuel gage just
The octain starts to drop off when the fuel gets over 4 to 6 months i think.

BB 420 SEAC

[alan_driver]

THIS IS ONLY MY THEORY:

At the bottom of your tank it is likely there is some 'crap' tiny bits of anything. If you imagine every time you fill up, occasionally you might chip a bit of paint work in there a fly, some dust or grit.
This will sink to the bottom of the tank but is not normally a problem. However when the tank is very low, it may pick some of this debris and surely that cant be good for the engine.

THIS IS ONLY MY IDEA, SO COULD BE ALL WRONG.