[pektel]

I find it's more about HOW you fill it, than the number of times the fuel has been refined.

When my ronson jetlite runs out (quite often. Small reservoir) I flip the lighter upside down and purge until I can't hear the propellant anymore. Then I fill it while it's inverted with whatever can of butane (I've had it for probably 5 years, can't recall the name). I try not to shake up the butane can, give it 3 bursts of about 2 seconds each. Never had a problem.

There are 2 ingredients in a butane can. Fuel and propellant. You want to try to not mix them up too much. You want to fill your lighter with mostly fuel, not mostly propellant. Propellant doesn't keep a lighter lit. The fuel is heavier than the propellant, hence the inverted filling (when inverted, the fuel is closest to the nozzle on the butane can, with the propellant in the perfect place to do its job.)

Is it the proper way? No idea. But it's worked for me for years.