First, let's fill the thing. Turn the lighter upside-down. If the design allows, I like to place the top on a flat surface as I hold it. Better stability. Then simply uncap the butane and without shaking it, line up the nozzles and depress for three seconds. Then stop for three seconds. Then fill it another three. Rest three. Fill three.
Three sets of three reps, bro. Voila. I really don't ever pay attention to fuel windows, but you can. Just don't fill for more than that three-count at a time. Now to discuss bleeding. When people say 'bleed,' they can apparently mean a couple of different things.
1. To let out some propellant particularly prior to refilling, situate all in the same manner as filling but instead of butane, stick the pick of a Czech tool or a paper clip (something metal not wooden) in and let that stuff burp-escape. This will offer a less sputtering experience for certain.
And 2. To completely empty a lighter of possibly bad butane or for transportation purposes perhaps, hold the thing right-side-up and deploy/employ that Czech tool/paper clip. This usage of the term bleeding seems far less common but I have witnessed it. I tend to think of this as 'purging' but that might just be me.
[Trouble-shooting a problem? Aren't we all? First, try bleeding (burping) it, then try emptying (purging) it. Refill completely after each of those efforts. If neither effort works, move on from fuel. Also, get good fuel.]
In the can of butane is said butane and also propellant. Same as in the lighter. This is why you don't want to shake the can (or the lighter) and also why we orient the lighter/can alignment as described. You do not want the fuel and propellant to mix or be in any sort of tuchus over teakettle position.
In short, disposable lighters are way under-rated and should never be looked down upon. Finally, whenever adding fuel, let it sit in the tank to acclimate for a few beats before sparking.
::: very :::
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