(c) Screw the charging-line fittings onto the check valves.
(d) Close bleeders.
(7) Charging. The operation of charging two pressure tanks from two cylinders is as follows:
(a) Close both filling-line valves.
(b) Open cylinder valves.
(c) Determine which cylinder has the lower pressure by the gages. Open the filling-line valve at the gage showing the lower pressure and fill the pressure tanks to the pressure shown by the gage. Close the valve. Then open the other filling-line valve and fill the pressure tanks until they reach pressures of at least 1,700 pounds per square inch as shown by the gage.
(d) When the pressure tanks have been filled, close the filling-line valves. Open the bleeders on the charging lines and leave them open until the pressure in the charging lines is released. Then close bleeders. Remove the charging-line fittings from the check valves. Screw the threaded caps on the check valves and tighten caps with a wrench.
(e) Repeat steps in (a) through (d) above for as many pairs of empty flame-thrower tanks as require charging.
(8) To insure proper pressure. Care should be taken to make certain that the compression delivered to the flame-thrower pressure tank is a full 1,700 pounds per square inch.
(a) If a filling-line valve leaks, tighten the packing nut on the valve with a wrench.