(1) Damaged parts. Replace worn or damaged parts. If the diaphragm shows evidence of tears or separation, or if leaks occur at the diaphragm, replace the valve-diaphragm assembly.
(2) Valve spring. If valve spring has lost resiliency, grasp it by the ends and stretch slightly, or replace.
(3) Nozzle leaks. If valve leaks at nozzle, and cleaning ([Par 55 d]) does not remedy the leak, adjust needle (see [d] above). If leak persists, either replace barrel and needle, or lap seat. To lap, place lapping compound on seat (in nozzle) and on needle point. Turn needle in seat until parts make a tight connection when seated. Remove lapping compound, reassemble, adjust needle, and test fire.
(4) Atomizer hole. If atomizer hole is clogged, clean with fine wire. ([Par 52 i])
76. IGNITION HEAD.
a. Description and functioning. ([Fig 55]) The ignition head ignites the fuel when the flame thrower is fired. It is mounted on the fore part of the barrel. It consists of:
(1) Ignition-head body, which includes half of the front grip. Three set screws serve to tighten the ignition-head body to the barrel. The ignition-head body is made of aluminum.
(2) Trigger and trigger bearing, held between the ignition-head body and the coverplate by the trigger screw.
(3) Trigger rod, one end of which is held in the trigger bearing, the other extending through the ignition-head body. Pulling the trigger shoves the trigger rod forward, causing it to push a match in the ignition cylinder. The match ignites an incendiary charge in the ignition cylinder.
(4) Trigger spring, which hooks over a projection of the trigger and is held at its lower end by a screw, which is held in the ignition-head body. This spring pulls the trigger rod back from the firing position after the firer releases the trigger.