This is Curtsey of the:
Nothing happens when I open the valve 1/4 turn.
How This Part Works:
Turning open
the valve allows the pressurized fuel and air mixture to pass through
the valve body and into the generator. This pressure will then force
the mixture up and out the generator tip. The tip of the generator has
an extremely small orifice. The lantern and stove also has a "tip
cleaner" which will poke out the orifice and keep it open. When you
turn the valve open you should hear the fuel and air being released out
of the generator tip. The below picture shows a lantern-a stove is the
same.

For more information go to our Theory of Operation chapter.
Why it is Not Working Properly:
A lantern's
generator is right next to a hot mantle, perhaps two of them. A stove's
generator is right over a burning flame. All this heat is required but
it also has a drawback. Many of the impurities of camping fuel,
kerosene or gasoline is "cooked off" inside the generator and there it
sits. After time it will block off the orifice-ultimately to a point
where no pressurized fuel/air mixture can pass thought it.
How To Fix It:
The generator
is the heart of the lantern or stove and that is why they are available
for most appliances. I carry a wide range of generators for sale on
this website but you may be able to find the more common ones at a good
sporting goods store. Instructions for replacing a generator are
usually found on the back of the package.
A temporary fix that
sometimes works in a pinch is to aggressively operate the generator tip
cleaner stem. If you have a very old lantern with a "loop" generator
you don't have a tip cleaner stem. If you have a military lantern you
don't have a tip cleaner stem but you should have a "pricker" tool. If
you have a lantern with a "lever" on it, that controls your tip cleaner
stem. If you don't have a lever, or if you have a standard stove, the
tip cleaner stem is moved by operating the valve wheel.
So, if you have a lever,
turn it around and around about a dozen times. If you don't have a
lever or if you have a camping stove, turn the valve all the way open
and then all the way off about a dozen times. The lever on the camping
stove (up to light, down to burn) does not operate the tip cleaner!
This manipulation is going
to probe the generator orifice and hopefully will clean it out enough
to get the appliance running-for a little while. But, with this
symptom, the generator does need to be replaced.