i was half asleep this morning when Martin Lewis was on GMTV today talking about how to save money on fuel but managed to catch the drift of the normal sort of stuff. You know “don’t over fill your car”, “keep tyres inflated”, “look around for cheaper fuel”, “make use of supermarket money back schemes” that sort of thing but he also said something about not going past the clunk when filling the car full because this just goes into the overflow and is wasted money. This one hit me as i’m always doing that.

So I looked on his website and found this little bit “While filling up to full isn’t great as it adds weight to the car yet if you must, don’t keep going after the petrol nozzle ‘clunks’, because you’re overfilling.”

Is this true that it’s wasted money? I’ve filled up a few times to the point that the petrol is visible in the pipe but not overflowed, is this pipe not just an extension of the fuel tank and the petrol will run down the pipe and into the tank as fuel gets used or does it get dumped the moment i’m off the forecourt?

I don’t really know much about cars and their inner workings but i think this is just twoddle, am i right?

BS I believe.

where would it go? sounds like nonsense

you’re fine… on some cars you can see a very small hole around the very top of the filler neck – this is the overfill drain, and will just piss out onto the forecourt, to stop petrol accumulating around the filler hole if you spill it when pulling out… ooo er 😉 as long as you keep the petrol in the filler tube, you’re fine.

I think you probably are, i do that as well & not a drop goes on the floor.
He’s enthusiastic to say the least about helping people save money, but he’s a proper twunt.

The only place the fuel can go is into the tank. It would be illegal to have it spill out of any ‘overflow’ and there’s nowhere else for it to go is there?

What I think they mean is the breather pipe, which I think lets air out of the top of the tank above the point where the filler nozzle sits to stop fuel blowing back in your face. If the tank neck gets very full, a bit of fuel goes down it….

Most tanks do have an overflow fitted quite high up on the fuel tank filler. The overflow does drain via a tube onto the road. My old polo and newer passat both have one and if you overfilled the tank it would drain the excess onto the forecort.

In addition some cars are very hard to fill, my polo would click of after 1/3 of the tank and then you had to fill the rest of the tank at about half speed the only way to judge it was to watch the litres.

I guess he has a point, I have filled up my car then left it in the sun, the fuel expands with the heat and will find a way out whether its via the breather or filler cap. result – lost fuel

Complete BS

The really old filler caps used to vent through the cap itself and you could overfill and get a bit of seepage but it’s not much. New Ford’s are quite explicit about stopping after the first or second click but that’s less about waste and more about the weird filler holes working with automated filling stations over in planet america.

There is obviously some truth in it then, just not quite pi88ing out onto the floor.

Don’t you just love people who jump in and diss stuff without giving the matter any thought at all. The guys obviously not a complete ‘twonk’ otherwise he’d be completely discredited by now!

It’s Jeremy Vine Show syndrome here sometimes – you get the two extremes of opinions and views but the ‘middle ground’ gets ignored.