You can get a generator for the double burner stove for less than £10 delivered (from ebay, but brand new & still packaged). I bought a 2nd hand double burner stove from ebay last week, it still hasn't arrived yet but I'm already thinking about ordering a generator, or maybe even 2, as I don't want it letting me down when I'm in France, & it will be getting plenty of use. I've never used one before, but I've already come to the conclusion that it's cheaper to use unleaded & replace the generator every now & then, than to use any other type of fuel.
I replaced the generator tube last year on our stove for the first time, purchased in 2003 IIRC .
I'd suggest a spare pump cup as well. On out model of the stove it was a sort of flexible plastic, that split, making the stove unuseable. I replaced it with a leather cup (Ebay I imagine) which should last pretty much for ever. The can stiffen when left unused for a a few months, but work in a little oil or somesuch and it will be fine again.
If you're really keen, or really mean, you could always try cleaning the old generator, using a combination of Redex, Gunk and fresh petrol.
Just as an experiment, and not because I'm mean, I cleaned the generator from my lantern, which now works fine, and I keep it as a spare. But when I counted the cost of the Redex, the Gunk and the time it took, I don't think that I'll bother in the future. Much cheaper and faster just to replace the generator.
Btw - some people use a few drops of Redex mixed in with the petrol, claiming that this extends the life of the generator.
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