Evaporation rate
 

How long for it take for a tankful of gas to evaporated from a sealed gas tank of a car?

I was thinking of cars in parking garages that the upper floors collapsed but they were in the underground levels and survived.

gas looses pep
 

The lighter components evaporate before the heavier parts -gasoline has a longevity of say 2 years in a sealed container .Fluids will be left , but it wont work or be less effective if it burns depending on how long it has been kept .

additives can double this -as far as I can understand from reading that is .

Fuel system stabilizer is not a cure-all and it doesn't last forever. It must be mixed with fresh gas before the vehicle is stored, not added to already old gas. It can slow down the oxidation process and keep gas fresh for as long as 12 to15 months. If you're going to leave the vehicle parked for longer than that, you may want to drain the tank and refill with fresh fuel before returning the vehicle to service.

The problem isn't going to be evaporation but more poor quality of the fuel.

Thanks all.

Having had a vehicle that sat for about 9 months without running, I can say that what Cdnwolf mentions is pretty accurate. I had more problems with keeping the darn thing running to get it to a gas station than I did with there not being enough gas to do it. Water condensation, gas degradation and particulates all have a play in gas that's sat for a while. Sure, you might be able to strain gas of particulates, but you're still going to have water in the mix and gas degradation to contend with. It leads to a rough running engine.

So I'd say, depending on the humidity in the area and how "sealed" the tank really is, you've probably got 5 months or so before you start seeing a noticable difference in the performance of the gas. Evaporation probably wouldn't really take effect until years after no usage, but by then, the gas is so degraded and filled with water that it's useless.

Does diesel degrade as quickly and to the same extent as petrol? And what about fuel oil for shipping?

no
 

diesel takes alot longer to degrade -it is more stable.

I guess that properly stored it could last 3 - 4 years .

I have a hunch that parafffinum and oil products last even longer -the heavier the petro product , the longer it will keep.