Half right. The flame did tend to taper off as the pressure in the tank
decreased. The decrease was most rapid when starting from a full tank
as the space above the gasoline for air was minimal. Second pump up
took longer and lasted longer. The air pumped in by hand had little or
nothing to do with combustion. The stuff coming past the needle valve
was just gasoline until the tank was nearly empty. Combustion air was
drawn in through the vent holes beside the jet. The heat vaporized the
fuel but not in the tank. The passage below the main barrel was known
as the generator. Nomenclature and principal of operation identical
with the Coleman stove or lantern.

Bob Galloway

Unknown wrote:

,;
,;497) An old blowtorch -- of the style designed to heat a soldering
,; copper (which rests with its shank in the notch just above the
,; flame output end, and the shank near the handle goes in the
,; 'C'-shaped rest.
,;
,; It is either kerosene or gasoline fueled, and the tank has to be
,; hand-pumped to higher pressure before it is started. Once it is
,; going, the heat vaporizes fuel in the tank and maintains the
,; pressure.



No. You had to man the air pump occasionally to maintain air pressure
to force the fuel through the nozzle AND supply oxygen to the fuel.
Actually the fuel entered the manifold as a liquid not vapor (see
starting procedure below). The fuel tank remains cool during
operation.

I agree to what it is but the ones I saw and used had a built-in
"basin" under the cast piece shown. When you started a cold torch you
bled gasoline (white gas not kerosene) into that basin and lit it in
order to heat up the manifold hot enough to vaporize the fuel. Once
heated the valve was opened and the flame kept the manifold hot enough
to vaporize the entering liquid fuel.

These critters weren't quite loud enough to require ear protection.