Fuel measurement : Pump or split can?

[treequip]

An accurate mix is easy, just use a one shot or a dosing bottle

[GordonRochdale]

We filled a stihl combi can up at the pump the other day, 5L exact on the meter, and about 2cm above the 5 litre mark on the can. Can was on level ground.

[GordonRochdale]

Oh and the can was completely empty too

[DWestbrook]

An accurate mix is easy, just use a one shot or a dosing bottle

 

what about the accuracy of the petrol amount?

[treequip]

what about the accuracy of the petrol amount?

 

Seriously????

 

Pumps are regularly calibrated and even if they were out by a fraction it wouldn't make much difference

 

I have been boing it that way for decades and have yet to have a problem

[Burgess]

No you don't.

 

The trigger is the valve, it starts and stops metering from there.

 

Well it's past the trigger then. I'm not imagining the bit of fuel that comes out before i press the trigger when i put the nozzle in the cap.

[treequip]

Well it's past the trigger then. I'm not imagining the bit of fuel that comes out before i press the trigger when i put the nozzle in the cap.

 

That must be all of 50 or 60ml, if the bloke before you didn't tip it in:laugh1:

[Burgess]

Yeah it is nothing. But I was trying to make the point about doing it at exactly 5.00.

[DWestbrook]

Seriously????

 

Pumps are regularly calibrated and even if they were out by a fraction it wouldn't make much difference

 

I have been boing it that way for decades and have yet to have a problem

 

Yes i was being serious

 

I was thinking along the lines of the pumps being purposefully incorrect.

 

sure its an offence, that weights and measures would be quick to act on i imagine.

But does it happen?(or indeed has it?)

[Mark_Skyland]

My suggestion is to mix as big a quantity as you can.

 

We always mixed 20 litres to 400ml at a time.

 

The chance of getting it inaccurate are reduced plus any discrepancy in fuel and oil quantities is reduced.

 

I would presume fuel pumps are fairly accurate but IIRC someone, somewhere on the internet or in a pub did some research and the findings were that if you feather the pump ie on/off/on/off etc then you get slightly less fuel.

 

Although not too good for the wallet it isnt the worst scenario for the saws.