Does petrol go bad?

[volvorocks]

Originally Posted by Backhill1

Think time to sell if not using, I had this with my defender kept it for the winter and never used other than that and the damage I was doing leaving it lying was unreal!
Brake cylinders annually, pads and disks , prop and all sorts of bearings not getting lubed (all splash). Eventually gave up as I was ruining it. And I was never going to jump in an old rough 4x4 when u have a nice comfy Volvo with heated seats are u?

Not an option to sell really.It was the other half's when she passed her test some years ago.She then got a new car, and the s40 is parked at my fathers, as he has an in out drive, just big enough for lorries and large vehicles to park, which are left there for days on end,making entrance and exit hard, and dangerous, not to mention blocking light and view,plus no one can see behind a large high vehicle so break ins etc may go on unnoticed, as they provide cover etc.

Its used from time to time to keep it oiled,and so nothing seriously sticks, and left idling to charge the battery, lubricate the engine etc etc.Passes mot fine each year (or at least for the last 4) so hopefully for at least the next 4?..!!

Regards

[Daim]

It depends on which fuel mixture you have. If 100% petrol, then it will take a while for it to go 'off' as it doesn't rot, oxidise etc. If you have 95% petrol, 5% ethanol (E5) then it will draw water. That doesn't take long. The petrol will then be resting on water at the bottom of the tank. If you have 90% petrol, 10% ethanol, then it draws even more water and that contaminates the fuel.

Also, modern fuels are more combustable than older ones, but don't like to sit too long.100% petrol is the best to let sit for a while...

So depending on what has been filled into the tank, it will be fine or contain a little water or a little bit more water.

PS: if a car has a metal tank, it should be filled to the brim, to stop the tank rusting inside... Just as a side note

[volvorocks]

Hi Daim

I have no idea what the fuel tank is made of, its an old s40. Also no idea what the petrol consists of, as I just go to the petrol station and fill up!

Regards

[Blandy15]

I always used to fill my bikes to the brim before packing away for the winter so no air gap and exposed tank to rust never had a problem starting again when the weather got better.

[Gazdok]

I can only comment from the biking point of view. As said by TT82 before when you wrapped up the bike for winter in the days of carbs you did 2 things to the tank and carbs.
Either completely empty the tank or completely fill it to the brim. This reduced the risk of water collection at the bottom and rusting through. The other thing we used to do was to empty the carbs because petrol will evaporate slowly and any impuritis / dirt will then concentrate and clog up small ducts in the carb. I always filled the tank to the brim. Petrol never went off over the winter months.

[Anadinolin]

After a year and a half it turns to jelly in my experience, good for lighting fires with, but not running dirtbikes

[Marty Dolomite]

Modern fuel will start to 'go off' in a few months and although most cars will still run on older fuel it will not run 100%.

[Bernard333]

I bought a V70 for spares from a forum member in 2009 and he very kindly left well over half a tank of petrol in it , still not put any petrol in and it starts first time and runs smoothly , I think the V70 tank is well sealed which helps avoid loss through evaporation . A different V70 with the sender/in tank seal removed but covered , the three gallons of petrol evaporated completely within 6 weeks leaving a tar like brown deposit in the bottom of the tank , I think I probably need to clean it out properly before starting it again .

[Bill_56]

Evidence that petrol 'goes off' can be seen by anybody who has left a lawn mower full of petrol over winter. The maker's instructions usually tell to run it dry at end of the season. Disobey that and whilst you may be lucky, chances are the carb will need stripping and cleaning come the new season.

[volvo145]

Petrol will go sour.
In the spring a lot of people take there garden machinery to get repaired at the start of the season because of starting issues.
The first thing the mechanic will do is change the fuel and it will normally start.
Something for the gardeners on here to bear in mind for the future .