This is a way off-topic, but you folks are some of the most technical guys I know.

I filled up the lawnmower gas can today with 8L of gas.   At least it was 8L as measured on the gas can.   The pump said I put in 9.5L.

So the pump said it put 20% more gas in the can than is actually there?

Has anyone ever experienced the same?  

I am going to measure the gas can for accuracy, but in the interim I'm looking for other's experience.

This was in the news lately, although from what I remember, the price on the pump was off from the amount pumped.  ie:  assume gas is 0.90 a litre.  You pump 10L (and actually get 10L of fuel), the price should be $9.00....although these pumps were reading $10.50.

So...they recommended pumping 10L of fuel, and comparing it to the price per L.

Not exactly the same problem you had, though, where the price per L was correct, but it was just pumping less fuel than it stated.

Did you bring this to the attention of the gas station?  If so, what did they say?

are there not 2 different L? a US L and a Metric L?

or is that some other measurement.

Gas cans are never accurate. But yes... you might want to check it out. Measure 8L using a measuring cup and put it in.

I did bring it to the clerk's attention.   Bish, it seems they had heard of that news, as they were wondering about a pricing issue.  

Both of them look surprised, and both inspected my red-can.   They offerred me a $1.50 back, but I was more interested in the why.   They took my information and promised their supervisor would call me back at lunch time.

False alarm though.
I measured the gas can and it actually had the 9.5L of gas in it (although it was showing only 8L).    I've been boycotting this ESSO for 2 years or so, as I thought their pumps were rigged.   Last time (2 years ago) I filled it slowly and thought that might have been the issue.  

Oh well, its just the gas can's fault.  

Quoted from Sparky

Gas cans are never accurate.

You can say that again - not even close - off by 20%.   I knew you couldn't use them for "official trade" or whatever postal-scales used to warn about, but I didn't think they that random.

I had seen one of the Canadian consumer shows tested some pumps, but in their tests it was always filling a large gas tank at "full throttle".   I was thinking that at "half throttle" it was off by 20%....

Oh well, another one of my conspiracy theories down the drain.... ...kids had fun though, measuring, counting and cleaning up the "spills" watching the rainbows go down the driveway  

Quoted from Pharoah007

are there not 2 different L? a US L and a Metric L?

or is that some other measurement.

I hope there's no USA Litre measurement, but I wouldn't put it past them  

Quoted from Pharoah007

are there not 2 different L? a US L and a Metric L?

or is that some other measurement.

I think you are thinking of Gallons...

1 US liquid Gallon = 3.8 L
1 US Dry Gallon = 4.4L
1 Imperial (UK) Gallon = 4.5L

Quoted from Pharoah007

are there not 2 different L? a US L and a Metric L?

or is that some other measurement.

Gallons.

Imperial: 4.54609 litres
US: 3.7854 litres

20% difference.

In case you are bored: http://en.wikipedia.org/wiki/Comparison_of_the_imperial_and_US_customary_measurement_systems

It is also important to note that the measurements are done at a specific temperature shown on the pump. Allowing for the temperature gradient may explain some of the discrepancy.

A Litre is a Litre. It's based on a cubic metric measure of volume.

As Mbug stated the difference is when you convert the number of L that go into a U.S. gallon vice and Imperial gallon because they are not the same.

They screw around with paint a lot in terms of converting a U.S. or Imperial gallon to make it seem like your getting the same amount of paint but the can is smaller i.e. it's a US gallon. Easiest thing is to compare the number of Litres from can to can.

I had gas cans do that to me a few times.
My gas cans i forgot to let air in the can and expanded allot so when i filled it it took more.