how is petrol measured at the pump?

SPANIEL36

i've often wondered this whilst filling up at petrol stations.... how is the amount you put in calculated. say for example i want to put £10 worth in, is it £10 worth that leaves the pump or what goes in the car? i always tip up the hose to get the last bits out before putting the nozzle back as i dont want to leave my last couple of pense in the hose for someone else when its so expensive anyway,

Can anyone shed any light on my random question??:o

shockingmoment

Good question.

The hose is always left full. There is a valve located in the nozzle that is activated when you squeeze the trigger. This allows the fuel to flow. When you release the trigger - the valve closes, again leaving the hose full.

There will be a little bit of fuel left in the nozzle so its a good idea to raise the handle to empty it. I always do this! Only pennies worth!

A more interesting question is - how does the automatic shutoff work when the tank is full?

KillerWatt

shockingmoment wrote: »

A more interesting question is - how does the automatic shutoff work when the tank is full?

It works by vacuum

ajbell

Its delivered by volume also, so you get more if you fill up when its cold as fuel is more dense then.

CHR15

shockingmoment wrote: »

A more interesting question is - how does the automatic shutoff work when the tank is full?

Look in the end of the nozzle.

There is a the big pipe the fuel comes out of, and a little pipe. The little pipe sucks air in.

When the fuel blocks the end of the little pipe stopping anymore air getting sucked in, it shuts off.

Hammyman

SPANIEL36 wrote: »

i always tip up the hose to get the last bits out before putting the nozzle back as i dont want to leave my last couple of pense in the hose for someone else when its so expensive anyway,
o

Why? When you let go of the trigger, it stops the petrol coming out of the hose so the only bit you're going to get out is the few drops sat in the metal tube after the trigger.

akh43

What I don't understand is why the prices still say, for example, £1.13.9, who do they think they are kidding? In the old days when petrol what cheap this seemed to make sense but nowadays it doesn't it just kids (they hope) you into thinking you are paying £1.13!

Is there a reason for this way of pricing other than to kid drivers they are paying less? Its not as if you can ever pay the .9 surely they must round it up to the penny.

Hammyman

akh43 wrote: »

Is there a reason for this way of pricing other than to kid drivers they are paying less? Its not as if you can ever pay the .9 surely they must round it up to the penny.

Its psychological. 99p sounds cheaper than £1. £99 sounds cheaper than £100. £1.139 sounds cheaper than £1.14.

Its not rounded up. Put in 10L and the price will be £11.39

sandford6016

Hammyman wrote: »

Its psychological. 99p sounds cheaper than £1. £99 sounds cheaper than £100. £1.139 sounds cheaper than £1.14.

Its not rounded up. Put in 10L and the price will be £11.39

.... But put in 1L and expect to pay the advertised £1.139?! How would they give you the change from £1.14!?!

Kilty_2

sandford6016 wrote: »

.... But put in 1L and expect to pay the advertised £1.139?! How would they give you the change from £1.14!?!

Well minimum delivery is usually 2 litres so you should be wondering how they'll charge you £2.278 really :rotfl: