Petrol Pumps

[DITTRICH]

A quick silly question.
How does a petrol pump know when the tank gets full?
Rgs
Les

 

[peterchurch]

I think it has a sensor that detects the fumes in the nozzel and uses this to guage the flow

 

[sym]

http://auto.howstuffworks.com/question25.htm

here's how !

 

[GrahamC230K]

If you are getting pump cut outs when you weren't expecting the tank to be full, read here:

http://mbclub.co.uk/forums/showthread.php?t=3415

 

[uumode]

A quick silly question.
How does a petrol pump know when the tank gets full?
Rgs
Les

Esso pumps seem to cause fuel to spill out over the side of my car
with their not so quick sensors.

Some are premature, so I think although they may be based on the same principle they don't work in the same way.

 

[DITTRICH]

...thanks. Those who have read my other thread about fuel consumption will have understood why I asked the question. I am about to monitor the fuel consumption of my vehicle quite precisely under various conditions because I think its increasing. So now I know that I need to insert the nozzle with the same orientation each time, and preferably use the same fuel pump each time in order to eliminate pump related factors. Note that its not so much the cost of the fuel, but the possibility something else more expensive might need some attention at some point.
Rgds
Les

 

[uumode]

I am about to monitor the fuel consumption of my vehicle quite precisely under various conditions because I think its increasing. ..... and preferably use the same fuel pump each time in order to eliminate pump related factors.

Yep, I've found that sometimes I get very bad consumption calculations because I reckon they short changed me i.e. the pump reading displays more litres than it's actually put in! Which isn't inconceivable, but I don't know what the tolarences are +/- 0.5 litre, +/- 4 litres?

/EDIT sometimes I'm paranoid, when somebody starts to operate the pump from the other side, as it sonically appears to be sapping power from the (shared?) pump (sonically dispensing the fuel at a less rapid rate) while the digital counter on the pump changes at the same rapid pace.

 

[DITTRICH]

Dear uumode
This begs the question about people who try to squeeze a bit more fuel into the tank by moving the nozzle and pressing the handle again. I've often felt that this wasn't effective and that I would be paying for far more fuel than actually came out of the nozzle. I had orginally intended to fill up frequently and often for my *big* fuel experiment but now I think I'll let the tank down to somewhere between 3/4 and reserve before refilling.
My fuel consumption results will be posted when there's enough data to make sense.
Rgds
Les

 

[glojo]

Yep, I've found that sometimes I get very bad consumption calculations because I reckon they short changed me i.e. the pump reading displays more litres than it's actually put in! Which isn't inconceivable, but I don't know what the tolarences are +/- 0.5 litre, +/- 4 litres?

/EDIT sometimes I'm paranoid, when somebody starts to operate the pump from the other side, as it sonically appears to be sapping power from the (shared?) pump (sonically dispensing the fuel at a less rapid rate) while the digital counter on the pump changes at the same rapid pace.

Two points I would like to raise.

1. It has been known for fuel pumps to have been 'tampered with' If you genuinely suspect you are being 'short changed' (short fueled) Then contact Trading Standards.

2. Beware when filling the vehicle to the absolute limit as you might end up 'watering' roundabouts and sharp bends.

Good idea though Dittrich to monitor fuel consumption.

Regards,
John

 

[DITTRICH]

For my fuel experiment, I'd intended only to fill until the pump FIRST cuts out.
That way, a 'full' tank of fuel should be about the same every time.