Always fill up on a cold day
An odd thing happened earlier this week. On the weekend, I filled the car up with petrol. It's an old Mazda Capella and the filler nozzle on the new unleaded pumps doesn't fit properly, so it's easy to overfill. Anyway, I probably put a bit much in this time, but no drama, and I drove away.
Is has been bloody cold lately but on Tuesday we had an unusually hot day. I was sitting in my office when the landlord's daughter came in and told me something was dripping from the car and it smelled like petrol. I went out, and sure enough, there was petrol dripping from just under the rear guard next to the filler. My first thought was a leak, so I popped the flap and opened the filler and out came about a cup full of petrol. Well that's weird I thought, because I'd done a few K's since filling it up, so how could that happen?
It seems that what has happened is that the petrol has expanded, as it does, because it was freezing the day I filled up and hot on this day. I had managed to fit more petrol in there than the tank could hold at the warmer temp, even though I had used a up a bit of it in the meantime.
So the moral to the story is that if you fill up on a cold day, you get more for the same price, because the mass to volume ratio goes up the colder it is. But make sure you don't overfill, or some of the profit runs down the drain. :o
I suppose this is factored into the price but it's worth taking advantage of when fuel is currently around $1.45 a litre :eek: