Under the designed tank pressure. I think the micra filler cap is designed to release pressure if too high.
Micra fuel tank leak
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The information on this china cap reveals various characteristics of the fuel tank, which is likely to be universal.
The inner side appears to have some kind of air pressure handling mechanism. Although it could just be part of the clicker device.
The inner side appears to have some kind of air pressure handling mechanism. Although it could just be part of the clicker device.
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Petrol is a liquid, dumbo.
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From you. you said.... a potential lack of a full seal at the cap.
Gravity.
Next
Hydrogen is a liquid too if given enough pressure.
So, you are none the wiser if I didn't tell you about it. I was assuming you were answering whether an air leak was an MOT fail. But you appear not. The gist of it is I have a pass, unless I tell the tester I have an air leak.
Car body shell is in way of the petrol fume "rain". There is nothing at the bottom to clean.
If your tank is open to atmosphere, via a hole, then the evap system cannot do it's thing. The evap system, regularly evacuate the fumes in the tank, and burns them in the engine.
All fluids can be in three states, a solid, liquid, or a gas. The differing states, are dependent on a combination of temperature and pressure.
Not really. The evap system didn't do a single thing for 6 months or more. The built up evaporation jetted out the cap continuously for the same period.
Petrol is gaseous in typical environmental conditions, unless pressurised, or frozen.
Which is perfectly normal, and means your tank had no holes in it - read the warning, on the cap, which you yourself posted.
Petrol, is a volatile liquid, which at normal temperatures, is just on the point of evaporation - which basically means it can be either a liquid, or a gas. It doesn't require much pressure, or much concentration above it, in a gaseous state, for it to be maintained as a liquid. In other words, it doesn't need much, to keep it in the liquid state.
Which explains why, despite tanks having a breather hole, in the past, the petrol didn't instantly evaporate. Anymore than you leak at the filler pipe, caused your entire tank of fuel to evaporate.
My tractor had a full tank of fuel, when last used September/October. I pulled it out just yesterday, to inflate the tyres, and check it over, ready to cut the grass, for the first time later this week. The tank has an open breather system. The fuel tank was, as expected, still full yesterday, no measurable evaporation I could detect.
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And water is a solid when cold enough, liquid at room temperature and gas when hot enough. What’s your point? Petrol is a fluid when you buy it and when you store it. It’s not a gas.
Stop trying to use common sense, it's wasted effort in any DiyNutJob thread.
Someone quoted a US study that proves you wrong.
My guess is your tractor is special. Is it a toy one? All other tractors are diesel. I believe diesel is "heavier" and evaporates differently to petrol. An extremely refined fuel used by planes will go gaseous even faster. Liquid rocket fuel goes gaseous faster still. Faster the burn required, faster they evaporate.
