Department of Defense Technical Manual
TM 3-376A

PORTABLE

FLAME THROWER

M2-2

CLASSIFIED

WAR DEPARTMENT,    
Washington, D.C. May 16, 1944

TM 3-376A, Portable Flame Thrower M2-2 is published for the information and guidance of everyone involved.

[A. G. 300.7 (March 21, 1944)]

By order of the Secretary of War:

G. C. MARSHALL,
Chief of Staff.

Official:
J. A. ULIO
Major General,
The Adjutant General.

Distribution:
R & H (5); Bn 2, 7, 17 (2); C & H 3 (5); IC & H 5 (5); C 2, 7, 17 (2); X. ID: T/O & E 72T, Light Division; 17, Armored Division; IR: T/O 5-192, Headquarters & Headquarters Company, Engineer Combat Group; 5-171, Engineer Combat Regiment; IBn: T/O 5-15, Engineer Combat Battalion; 5-35, Engineer Battalion Separate; 5-175, Engineer Battalion, Combat Regiment; 5-215, Armored Engineer Battalion; 5-475T, Engineer Battalion, Light Division; IC: T/O 5-16, Headquarters & Headquarters & Service Company, Engineer Combat Battalion; 5-17, Engineer Combat Company; 5-192, Headquarters & Headquarters Company, Engineer Combat Group; 5-36, Headquarters & Headquarters & Service Company, Engineer Battalion (Separate); 5-37, Company, Engineer Battalion (Separate); 5-176, Headquarters & Headquarters Detachment, Engineer Battalion, Engineer Combat Regiment; 5-216, Headquarters & Headquarters Company, Armored Engineer Battalion; 5-217, Company, Armored Engineer Battalion; 5-476T, Headquarters & Headquarters Company, Engineer Battalion, Light Division; 5477-T, Company, Engineer Battalion, Light Division.

(For explanation of symbols see Par 26, FM 21-6)

1

WAR DEPARTMENT    
Washington State, 25, D. C., May 16, 1945

Updates}
   No. 1   }

TM 3-376A, 16 May 1944, is updated as follows:
10. ITEMS INCLUDED WITH EACH FLAME THROWER.

*****

b. Kit, spare parts, for portable flamethrower M2-2, assembly B81-6-190.

*** **

g. (Added). Army Service Forces Catalog CW 7-440114, Organizational Spare Parts and Equipment: 1st and 2nd Echelons: for Flame Thrower, Portable, M2-2.

__A_TAG_PLACEHOLDER_0__. Tool kit contents:

** ***

** ***

__A_TAG_PLACEHOLDER_0__. Spare parts kit items:

12. NEW GEAR.

*****

m. (Added). A new gun may come with the valve spring removed from the barrel and valve assembly. The spring is secured to the barrel to avoid any strain on the valve diaphragm assembly caused by the spring's pressure in the gun during storage and shipping. When getting the weapon ready for use, the spring must be untied from the barrel and installed in the gun, as detailed in paragraph 75.

n. (Added). The pressure regulator may be sent out with zero adjustment to avoid any strain on the diaphragm during shipping and storage. A regulator shipped like this has a tag (attached to the [2] tank coupling) indicating that the regulator is not set. When the weapon is received in this state, it must be adjusted as described in paragraph 67 before it can be used.

15. TRAINING.

*****

b. Use of water in training. Water can be used (instead of fuel) for basic practice firing. Ignition cylinders are * * * piece, and lubricated (Par. 49). However, using water should always be backed up by firing ignited fuel because water doesn't provide an accurate representation of stream and flame characteristics.

*****

17. CONNECTING TANK GROUP AND GUN GROUP.

*****

a. Place the new * * * for 2 minutes. Sometimes, slight pressure builds up in the fuel tanks, even if the pressure-tank valve hasn’t been opened, which can cause some fuel to overflow when the coupling plug is removed. This pressure can be relieved by—

(1) Position the tank group upright.

(2) Slightly open the filling plug on top of the fuel tanks to relieve the pressure.

(3) Sealing the opening at the fill plug and tightening it with a wrench.

*****

18. Loading with ignition key.

** ***

b. Precautions. Care must be taken * * * in front of the gun. Do not ignite the ignition cartridge until you are ready to fire the weapon at the target.

*****

30. AFTER FIRING.

When the person in charge of firing * * * the mission, they should:

a. First, take out and throw away the ignition cylinder, since the ignition cylinder should never be there when clearing out fuel or after clearing out fuel unless you’re getting ready for a new mission. To remove the cylinder, follow these steps:

** ***

b. Close the pressure tank valve by turning the valve handle clockwise (to save the remaining pressure in the pressure tank) only if more shots are going to be fired before refilling and recharging.

3

c. If no more shots are going to be fired before refilling and recharging, open the pressure tank valve by turning the handle counterclockwise. Point the gun away from people and release any remaining fuel and pressure from the fuel tanks by squeezing the valve lever and grip safety until no more fuel comes out. The trigger should not be used during this process. After that, close the pressure tank valve to keep any foreign matter from getting into the pressure system.

d. (Superseded). Gently take the tank group off your back. The easiest way to do this is to sit or squat with your back against a tree stump, flat rock, packing box, or any other sturdy object. Unbuckle the body and shoulder straps and carefully lift the tank group off. Be careful not to drop the equipment on the ground, as it could get damaged.

*****

31. Ignition Cylinder.

** ***

c. Packing. Ignition cylinders are * * * each flamethrower. Fifty cans (100 ignition cylinders) are packed in each ignition cylinder box. The wooden packing box with contents weighs about 50 to 55 pounds. The external dimensions of the box are approximately 16-1/4 inches by 14-3/4 inches by 10-1/4 inches. The volume is 1-3/12 cubic feet.

*****

32. Filling Pressure Tank.

*****

b. Charging from air compressor. Compressor, air, gasoline * * * cylinders as well. Instructions for use of the compressor will be found in TM 3-377.

*****

Figure 23. Charging two pressure tanks with charging and filling lines, and cylinders filled with compressed air or nitrogen. Up to four pressure tank and valve assemblies, whether connected to or separate from tank groups, can be charged simultaneously from cylinders connected as shown in figure 24.

33. SAFETY TIPS FOR PRESSURE CHARGING.

** ***

m. (Added). Inspect carefully to ensure that there are no traces of grease, flame thrower fuel, oil, dirt, or any other foreign substances in the flame thrower pressure tanks, air compressor outlets, connections, hoses, or cylinders that contain compressed air.

n. (Added). Hands and tools must be free of oil or grease when charging or servicing flamethrower pressure systems.

4

o. (Added). Release any remaining compressed air in the flamethrower pressure tanks before refilling.

p. (Added). If you're using compressed air, and you notice any grease, oil, or fuel from a flame thrower by smell or sight inside the pressure tank, valve assemblies, or cylinders, return the tanks or cylinders for cleaning to the correct third-echelon maintenance agency of the Chemical Warfare Service.

35.1 Peptized Fuels (Added).

a. Features.

(1) Pour thicker fuels more easily than normal.

(2) Provide a wider flame diameter than thick fuels.

(3) Provide longer effective ranges than liquid fuels.

(4) Prepares faster in cool temperatures than thick fuels.

b. Preparation.

(1) Open a 5-1/4-pound can or cans of thickener.

(2) Add 2 mess kit spoonfuls of water to each can of thickener. Stir until the water is fully absorbed by the thickener. You don't need to mix the water evenly with all of the thickener.

(3) Go ahead immediately as instructed in paragraph 35. Make sure not to accidentally add any water to the thickener or fuel beyond what is mentioned in (2) above.

(4) Peptized fuels set a bit faster than regular thickened fuels, but they look the same after setting. However, after a while, peptized fuels naturally become thinner and can be poured without any pressure. The time it takes for thinning to happen depends on the temperature of the fuel. At 75° Fahrenheit or higher, thinning happens in about 1 to 2 hours. At temperatures below 60° Fahrenheit, thinning takes several days after the peptized fuel is prepared.

(5) If water accidentally gets into the fuel before adding the thickener, it causes a peptizing effect, but the results are unpredictable since the amount of water added isn't controlled.

36. Liquid Fuel Preparation.

a. Choice of ingredients. Thin fuels are * * * reaching the target. For this reason, liquid fuels should have the lowest amount of gasoline and the highest amount of heavier fuels that allow for easy ignition. In hot climates, * * * of great importance. The gasoline used can be any U.S. grade of motor fuel or aviation gasoline. Suitable blends are as follows:

5

*****

(3) (Added). By volume, 20 to 25 percent gasoline and 75 to 80 percent light fuel oil.

** ***

40.1 USE OF PACKBOARDS (Added).

Detachable pressure tank and valve assemblies (par. 66.1) allow for the use of packboards to carry pressure tanks, 5-gallon fuel cans, wrenches, and extra ignition cylinders close to the front lines for troops using flamethrowers. Since packboards aren’t specifically made for servicing flamethrowers, standard quartermaster-issued packboards are used instead. Packboard transportation works only with pourable fuel. (Pourable fuels include some thickened fuels and all liquid fuels.)

a. Here’s a suggested procedure for using a packboard for transportation:

(1) Secure all the necessary filling and charging supplies for one flamethrower to the packboard, using lashing rope and straps.

(2) Attach one pressure tank and valve assembly to the top of a flat 5-gallon fuel can so that the flexible shaft and handle hang down parallel to one side of the fuel can.

(3) Carry a wrench with a wide enough opening to unscrew the filling plugs from the tops of fuel tanks and to tighten the plugs after filling.

Carry spare ignition cylinders.

b. Return the empty pressure tank and valve assembly, along with the empty fuel can and wrench on the packboard, to the flamethrower service point.

c. If there is a supply of flamethrower tank groups available, they might be favored over the packboard method of transportation. Tank groups are easy to carry, and a filled and charged tank group can replace an empty one just as quickly as the packboard method can service a flamethrower.

*****

48. Service Kit.

** ***

a. Tools.

** ***

*****

6

b. Accessories and spare parts.

*****

*****

49. LUBRICATION.

a. Firearm organization.

*****

(2) Frequency of lubrication. The surfaces of * * * should be lubricated before reassembly. Do not soak or wash the spring case assembly in solvent because this may remove the grease that is factory packed in the spring case assembly. This grease cannot be replaced. To clean the spring case assembly, wipe the outside surfaces with a cloth soaked in solvent.

7

** ***

53. SERVICE WHEN FILLING AND CHARGING.

** ***

d. Testing for leaks in the pressure system. After charging and * * * to test pressure. (Fig. 32.) To install the gauge, unscrew the check-valve cap, moisten the end of the check valve with water or saliva, and screw the gauge into the check-valve body. Using water or saliva as a lubricant prevents cutting the rubber washer by the check valve. If the pressure has * * * and then retested.

66. Pressure Tank and Valve Assembly.

a. Description and functioning. The pressure tank * * * assembly (Fig. 33) includes:

(1) Pressure tank. The pressure tank * * * the fuel tanks. You can adjust the pressure-tank clamp to fit different outside diameters of pressure tanks using a nut and screw tightening device (fig. 35.1) or by using a stepped ring at the end of the clamp.

** ***

b. Removal. (__A_TAG_PLACEHOLDER_0__.)

*****

(2) Extraction process.

** ***

(h) (Added). To take off the check valve, unscrew the check valve cap and the check valve body with wrenches.

8

c. Setup. (Figs. __A_TAG_PLACEHOLDER_0__ and __A_TAG_PLACEHOLDER_1__.)

** ***

(7) (Added). To install the check valve, lightly apply thread compound to the threads of the cheek valve body and screw it into the opening in the pressure-tank valve. Tighten the check valve body in position using a wrench. Screw the check valve cap onto the check valve body and tighten it with a wrench.

*****

66.1 DETACHABLE PRESSURE TANK AND VALVE ASSEMBLIES (Added).

Newly designed detachable pressure tank and valve assemblies offer a better and quicker way to service M2-2 portable flamethrowers in combat zones.

a. Description and functionality.

(1) Detachable pressure tank and valve assemblies (figs. 35.2 and 35.3) are used in updated flamethrowers. They eliminate the need to swap out empty tank units for full and charged ones.

(2) Replacing the entire tank group might be better when there's an extra supply of tank groups available, or if the thickened fuel is too sticky and thick to pour.

(3) Detachable pressure tank and valve assemblies can only be attached to flamethrowers that have sockets (figs. 35.2 and 35.3) and shortened regulator tubes. Recently made flamethrowers include this design update.

(4) A plug and cap (fig. 35.3) on the detachable pressure tank and valve assembly replace the tube elbow (fig. 33) used on the non-detachable pressure tank and valve assembly.

b. Removal. Care must be taken to avoid damaging connections during removal and installation. The procedure for taking out the pressure tank and valve assembly is as follows:

(1) Close the pressure tank valve. Press the valve lever and safety grip on the gun to release all pressure from the fuel system and the gun.

(2) Remove the wing nut from the valve's flexible shaft. (See fig. 35.4.) Be careful not to lose the wing nut.

(3) Remove the clamp and shaft from the stud that’s welded to the fuel tank.

(4) With one hand under the pressure tank, loosen the pressure-tank clamp, but don't fully open it.

(5) With your right hand, press the knurled socket in and away from the pressure tank valve. You can use your left hand to support the back of the regulator tube to prevent it from bending away from the socket. (See fig. 35.5.) Pull out the pressure tank and valve assembly.

9

10

11

12

(6) Push the cap as far as it will go over the opening of the plug. (See fig.35.6.) This stops dust and other foreign materials from getting into the empty pressure tank.

(7) The flame thrower is now ready to get a charged pressure tank and valve assembly. (See fig. 35.7.)

c. Installation. To install a charged or replacement removable pressure tank and valve assembly, follow these steps:

(1) Take off the dust cap from the plug of the charged pressure tank and valve assembly. (Never open the pressure tank valve while the cap is on the plug.)

(2) Support the socket and tube with your left hand and insert the plug into the socket with your right hand. If the tube isn't supported, it's hard to lock the plug into the socket, and the tube might get bent. Press the bottom of the tank until the plug snaps into the socket. Check by trying to pull the tank and plug out of the socket. The plug shouldn't come out; if it does, insert it again and press the bottom of the tank. Hold the knurled collar of the socket and check for any movement. If the collar slides back and forth freely on the socket, the connection isn't tight and the plug should be pushed in further.

13

14

(3) Replace the small clamp (valve-stem clamp) over the stud that sticks out from the fuel tank, and screw the wing nut onto the stud to secure the valve flexible shaft in place. Do not use a wrench on the wing nut.

d. Maintenance. Follow the maintenance instructions provided in paragraph 66. Additionally, if leaks happen and signs of wear are present, perform the following procedures:

(1) Worn washer. Replace the synthetic rubber washer by taking apart the socket (fig. 35.8), removing the old washer, placing the new washer in position, and reassembling the socket.

(2) Damaged plug. Fix the damaged or nicked end of the plug by filing it flat and smooth. Remove as little material as possible. Check for leaks at the socket by installing the pressure tank and valve assembly, as described in section c above, and then opening the pressure tank valve. If there’s still a leak at the joint between the socket and the plug, replace the plug by unscrewing the old one, screwing the new one into place, and tightening it with a wrench. Replace the entire plug. Do not try to unscrew the cylindrical part from the square part.

15

67. Pressure Regulator.

** ***

e. Maintenance (Updated).

(1) Spring type (Hoke) pressure regulator. Other than adjusting it to increase or decrease pressure, do not try to maintain or repair the spring type (Hoke) pressure regulator. If it's damaged or not working, it should be replaced with a dome type (Grove) pressure regulator.

(2) Dome type (Grove) pressure regulator (B81-1-778). Replacement parts for maintaining the dome type (Grove) regulator are available for use by chemical maintenance companies, as shown in Army Service Forces Catalog CW 9-440114, List of All Service Parts and Higher Echelon Spare Parts for Flame Thrower, Portable, M2-2 (25 November 1944).

74. Valve Grip.

** ***

c. Installing valve handle.

(1) Place the grip safety * * * on the right valve grip. (Fig. 48.) Do not accidentally position the lower forward extension of the grip safety over the lower rear extension of the valve lever. If this happens, the small projection at the bottom of the grip safety could break off. Make sure the * * * of the grip safety.

*****

77. Shipping and Storage.

** ***

c. Class of supply (Added). The portable flame thrower is a Class IV supply item.

78. REFERENCES.

Reference pertaining to **flame throwers include:**

*****

16

[AG 300.7 (11 Apr 45)]
By directive of the Secretary of War:

G. C. MARSHALL
Chief of Staff

Official:
J.A. ULIO
Major General
The Adjutant General

Distribution:

1

a. Setup. This manual is published to help and inform staff who use and maintain the portable flame thrower, M2-2. Part One contains general information; Part Two is an operational guide; Part Three provides maintenance steps. The Appendix covers shipping and storage procedures, along with relevant publications.

b. References. References are in the Appendix. The list includes field manuals, technical manuals, and Army Regulations.

Although no standard maintenance forms and records are provided, an informal list should be kept of how many times each flame thrower has been used. The list helps determine when to perform preventive maintenance and lubrication after six missions. It should be attached or glued to the inside of the packing-chest lid, and each flame thrower should always be returned to its respective chest.

Flame throwers can: a. Access openings, like embrasures and gun ports, and fill the fortifications with fire and smoke.

b. Burn, suffocate, and blind enemy soldiers., leading to injuries, shock, panic, and desertion of a stronghold.

c. Ignite the flammable areas of shelters and equipment. and begin detonating sensitive ammunition and explosives.

2

3

4

d. “Shoot around corners.,” refers to when fuel is ignited from hidden or obstructed angles. This is made possible by the swirling and billowing movements of burning gases. Thick, blazing fuels also bounce off walls in fortifications.

e. Make the enemy close the ports., temporarily putting the location out of service and thereby safeguarding the demolition team.

Mop up entrenched personnel.

g. Destroy enemy hideouts in urban or jungle combat.

a. Action. Fuel is pushed into the target using a blast of highly compressed air or nitrogen. As the fuel exits the gun of the M2-2 portable flamethrower (Fig 1), it ignites when it comes into contact with flames from incendiary mix stored in a disposable ignition cylinder.

b. Explosions. A steady flow or individual bursts can be fired for about 8 to 9 seconds, excluding the time between bursts. The five incendiary charges in the ignition cylinder are managed by the trigger and can ignite multiple bursts.

c. Scope. Portable flamethrowers are used at very close or point-blank range for optimal results. (Par 22) The effective range for liquid fuels (Fig 2) is up to 20 yards, and for thickened fuels (Fig 3), it's 40 yards, but underbrush and strong winds can shorten those distances.

d. Weight. To keep the weight as low as possible while still providing the strength to handle very high pressures, most components are made of aluminum or sheet steel.

e. Strategies. Usually, two or more flamethrowers are used during a mission alongside other weapons from the assault squad. (See FM 31-50, “Attack on a Fortified Position and Combat in Towns.”)

f. Shooters and helpers. One person carries and uses each flamethrower. Well-equipped assistants accompany the firers to provide close protection and to act as emergency backups. While the M1A1 portable flamethrower may need an assistant to open the pressure-tank valve, the M2-2 flamethrower’s pressure-tank valve is positioned within the firer’s reach and can be operated without help. Both firers and assistants should be thoroughly trained in the operation of the weapon.

g. Charging and refilling. To replace the pressure tanks (cylinders) on older flame throwers, you need to unscrew and screw in threaded connections. Experience has shown that this often leads to damaged threads, leaks, loss of pressure, and reduced range. You also have to use tools to change each pressure tank (cylinder). The design of the M2-2 flame thrower gets rid of these problems. The tank group (Fig 4) can be charged and filled as a unit, with or without the gun and hose. The quick-connect tank coupling allows for fast swapping of empty and full tank groups by the operators or assistants. 6 This can be done without tools, takes very little time, and won’t cause leaks, loss of pressure, or reduced range due to damaged threads.

The flamethrower is made up of two main parts: the tank group and the gun group. You can find detailed descriptions of the assemblies and parts in Paragraphs 66 through 76.

a. Tank squad. (Figs 4 and 5) Carried on the user's back, the tank group contains fuel and pressure. The tank group is identified as tank, fuel, portable flame thrower, M2, assembly D81-1-482. It mainly includes:

(1) Two gas tanks, holding a total of 4 gallons of fuel, and connected by a tank connector to create a single fuel reservoir.

(2) Pressure vessel, filled with highly compressed air or nitrogen, is used to push fuel from the fuel tanks through the gun to the target. The tank has a large capacity to ensure sufficient pressure and consistent long range during firing.

(3) Pressure tank valve, which releases air or nitrogen through the pressure regulator to the fuel tanks. The valve can be opened by the shooter without needing assistance, unlike the M1A1 flame thrower.

(4) Pressure regulator, which automatically ensures that air or nitrogen is delivered to the fuel tanks at the correct pressure. The regulator is placed in a location where it can't be easily damaged.

(5) Carrier, which holds the tank group on the shooter’s back and shoulders and attaches it to their body. It features body and shoulder straps along with quick-release fasteners.

b. Firearms organization. (Fig 6) Held, aimed, and operated by the shooter, the gun group ignites the fuel and directs the flame toward the target. It includes:

(1) Gas hose, which transports fuel from the tank group to the gun. The fuel hose can be ordered as hose, fuel, portable flame thrower, M1, assembly B81-1-498.

(2) Firearm, which ignites the fuel and directs it to the target. The gun can be recognized as a gun, portable flame thrower, M2, assembly D81-1-405. It includes:

(a) Fuel shutoff valve, which releases fuel through the barrel. The valve is activated by squeezing the valve lever and the grip safety, located on opposite sides of the valve grip. The valve also has a barrel from which the fuel is expelled. The ignition head is mounted at the front of the barrel.

(b) Ignition coil ignites the fuel as it moves from the nozzle of the barrel. Each time you pull the trigger on the front grip, one of the five charges of incendiary mix in an ignition cylinder is ignited. This pilot flame ignites the fuel as it is fired from the gun.

8

9

The terms “Chemical Warfare Service,” along with model numbers, serial numbers, lot numbers, weight, dimensions, manufacturers’ names, contract number, and packing date are listed on the packing chest or the equipment. The numbers and letters displayed on the equipment should be referenced when repairs are needed. The tank group and the gun (excluding the fuel hose) may each be labeled “M2,” while the fuel hose may be labeled “M1,” even though all these are parts of the M2-2 portable flame thrower.

a. M2-2 and E3 portable flamethrowers. The portable flame thrower M2-2 is the same in all key aspects as the portable flame thrower E3. (The E3 flame thrower, after standardization with some tweaks, was developed into the M2-2.) Operating and maintaining the M2-2 and E3 are generally the same, and the parts can be swapped out.

b. M2-2, M1, and M1A1 portable flamethrowers. The M2-2 portable flamethrower has the same fuel capacity but is built differently from the M1 and M1A1 portable flamethrowers. Parts are not interchangeable unless specified in Paragraph 8.

To use an M2-2 gun with the tank group (fuel unit) of an M1 or M1A1 portable flamethrower:

a. Take the fuel hose off the M2-2 gun.

b. Screw a 3/4-inch by 1/2-inch pipe bushing into the side opening of the fuel-valve body. This bushing comes with the spare parts kit of every M2-2 portable flamethrower. (Par 10)

c. Tighten the fuel-hose assembly of the M1 or M1A1 flamethrower into the 1/2-inch opening of the bushing, using a wrench to ensure a secure connection.

All data is approximate.

a. Range. See Paragraph __A_TAG_PLACEHOLDER_0__.

b. Fire duration.

Fuel

(a) Continuous discharge of about 8 to 9 seconds, or

(b) Several short bursts lasting about 8 to 9 seconds (excluding the time between bursts).

(2) Ignition switch. Five charges in each cylinder, 8 to 12 seconds for each charge.

10

g. Used supplies ratio. For every 100 full refills of the flamethrower, the following supplies are typically consumed:

(1) Nitrogen in fifteen 220-cubic-foot cylinders or a similar volume of compressed air. (If the four-cylinder setup mentioned in Paragraph 32 is used, eleven cylinders will be used.)

(2) 450 gallons of fuel (400 gallons plus an additional 50 gallons for spills, spoilage, and evaporation).

100 ignition cylinders.

(4) If you use thickened fuel, you'll need 135 pounds (in cans of 5-1/4 pounds each) of U.S. Army fuel thickener.

11

The items listed below or their equivalents (Fig 7) are included in each M2-2 flame-thrower packing chest, along with the flame thrower. The numbers next to the items are Chemical Warfare Service stock numbers.

a. Kit, tool, for portable flamethrower M2-2, assembly B81-6-50.

b. Kit, replacement parts for portable flamethrower M2-2, assembly B81-6-52.

c. Cylinder, ignition, portable flame thrower M1. (6 cylinders, in 3 cans with 2 each)

d. Technical Manual 3-376A, “Portable Flame Thrower M2-2.”

Gun mounting board. (__A_TAG_PLACEHOLDER_0__)

f. Plug, coupling, E81-1-514 (for use in tank coupling when filling the tank group with the gun removed).

12

13

14

Part Two of this manual is for the guidance of operating staff. It includes information on the controls and on how to operate them.

Upon receiving a new flamethrower, the following procedure should be followed:

a. Use pliers to cut the steel straps and seals on the packing chest.

b. Take out any screws from the top of the chest, if there are any.

c. Open the two latches at the front of the chest.

d. Lift the lid back and attach the chain from inside the chest to the inside of the lid.

Remove moisture-proof paper.

f. Take the gun out of the box. Once you've removed the waterproof tape from the ends of the hose, connect the hose to the gun. (Par 17)

g. Take off the mounting board and set the gun with the hose on the board as shown in Figure 10.

15

h. Take out the spare parts kit, tool kit, cans of ignition cylinders, and other items from the packing chest.

i. Compare the contents with the packing list found in or on the packing chest. Inspect all contents thoroughly for completeness, proper adjustment, and good condition.

j. Insert the deflector tube into the safety head on the left fuel tank. (Fig 11) The outlet should face towards the rear and be at a 45-degree angle to the operator’s left shoulder. (Fig 18) Screw in the deflector tube by hand; do not use a wrench on the deflector tube. Tighten the lock nut with a wrench.

k. Before using the weapon on a mission, test-fire it. (Par 56 b)

l. Keep the packing chest for storing the equipment when the flamethrower is not being transported on a mission or being serviced.

When they apply, the same steps should be taken as in Paragraph 12. Any worn or damaged parts should be replaced. Areas where paint has chipped should be refreshed with new paint.

The shooter uses the pressure-tank valve handle, the trigger, and the valve lever and grip safety (Fig 12) one after the other like this:

a. Valve lever. The pressure-tank valve is controlled by turning a handle on the valve's flexible shaft, which is within reach of the shooter. Turning the handle counterclockwise releases pressure to the fuel tanks. Turning it clockwise closes the valve.

b. Trigger. The trigger is located at the front grip of the gun. Pulling the trigger firmly ignites an explosive charge in the ignition cylinder. This, in turn, sets off the fuel as it exits the gun. The trigger action also causes the ignition cylinder to rotate one-fifth of a turn, bringing another charge into position for firing. Each of the five charges can thus be used in quick succession, if needed, by pulling the trigger firmly up to five times.16

c. Valve lever and grip safety. The valve lever and grip safety are placed on opposite sides of the gun's valve grip. When both controls are pressed, fuel is pushed out from the gun. If either the valve lever or the grip safety isn’t pressed, the fuel valve stays closed and the fuel stays in the weapon.

Effective use of the M2-2 portable flamethrower can only be achieved through careful practice with the weapon. Untrained operators or assistants should never be sent on a mission.

a. Practice. Shooters should train in different conditions involving wind, distance, elevation, lowering, and side movement. The limited time for firing (about 8 to 9 seconds) requires quick decision-making and coordination.

b. Using Water for Training. Water can be used (instead of fuel) for basic practice firing. Ignition cylinders are not used with water. Pressurized water can cause serious injuries to personnel at 10 yards. After practicing with water, the gun should be taken apart (Pars 73 through 76), cleaned and dried piece by piece, and then lubricated. (Par 49)

c. Fuel usage in training. When using fuel in training, choose or set up a practice area that is at least 125 yards for range and 30 yards for spread. If the area has dry grass, brush, or other flammable materials, a fire-fighting team with equipment and a water source should be on hand. Assistants and observers should remain far behind the firer due to the risk from wind changes. See Paragraph 40 for more safety precautions.

Before using flame throwers for missions or training, they need to be charged, filled, and serviced. Charging with compressed air or compressed nitrogen is covered in Paragraphs 32 and 33; filling with fuel in Paragraphs 34 through 40; and servicing in Paragraphs 50 through 56. Test for pressure. (Par 53 d)

If a charged and filled tank group has been set up to replace an emptied one:

a. Set the new tank group on the ground with the tank coupling17 facing up. If the filling is thickened fuel, let the tank group stay in this position for 1 to 2 minutes.

b. Take off the coupling plug from the new tank group and detach the gun group from the emptied tank group. Insert the unthreaded end of the fuel hose into the tank coupling and secure it. (Par 70)

c. Secure the coupling plug in the empty tank group.

a. General. Right before starting a mission, insert a new ignition cylinder into the ignition head. (M1 and E1 ignition cylinders are the same and can be used interchangeably.) Cylinders come in packs of two per can. Don't open the cans until you're ready to load for a mission. The second cylinder in the can should be used in another flamethrower during the same mission or as soon as possible after opening the can. Partially used cylinders can be used for training.

b. Safety measures. Always be careful when handling cylinders to prevent any impacts or pressure on the metal match ends. (Fig 13) Your face, hands, and other body parts should never be exposed to the front of the cylinder or the front of the gun.

18

c. Procedure. The loading process is as follows:

(1) Unscrew and take off the ignition shield. (Fig 14)

(2) Put the ignition cylinder on the end of the barrel (Fig 15), making sure not to hold the cylinder by its ends.

(3) Lift the nozzle end of the gun so the cylinder moves down against the spring case of the ignition head. (Fig 16) If needed, turn the cylinder so it fits down completely. Don't force the cylinder into position because doing so might ignite it too soon.

(4) Rotate the spring case and ignition cylinder clockwise until they can turn freely.

(5) Put the ignition shield over the cylinder. Fit the slot in the shield onto the pin of the spring case.

(6) Turn the shield, screwing it onto the ignition head body. Make sure the threads catch during the first turn of the shield. When the slot on the shield connects with the latch on the ignition head (Fig 17), the gun is loaded.

(7) If you can't turn the shield by hand tight enough to lock the latch, unscrew the shield. Then turn the shield counterclockwise until the threads engage and repeat (6) above.

20

21

The tanks are supported on the user’s back and secured with two shoulder straps and two pairs of body straps. (Fig 18) The straps can be adjusted with the buckles to fit the operator. The shoulder straps go over the shoulders and under the armpits; the lower body straps are fastened tightly in front of the body; and the upper body straps are secured across the chest to keep the shoulder straps from slipping and to stop the tank group from rolling off the back. Adjust the various straps until the unit is carried with the bottom of the fuel tanks at the small of the operator’s back. The tank group should fit snugly so it doesn’t shift if the operator moves quickly.

The process for carrying the gun is as follows:

a. Carry the gun with the hose on the right side. (Fig 19)

b. Hold the valve grip with your right hand and the front grip with your left hand, making sure not to use the controls until you’re ready to shoot.

c. Always keep the gun pointed away from other people.

d. Never point the front of the gun at anyone. Even when no fuel is being released, the explosive charges in the ignition cylinder can lead to serious burns.

e. Keep the gun dry and clean if you can. Avoid getting dirt or any foreign substances into the weapon.

Don't handle roughly.

Wear gloves if you have them.

h. Always carry spare ignition cylinders only in metal containers.

22

The release of pressure from the fuel tank makes a hissing sound. So, open the pressure tank valve while staying out of earshot of the enemy. But don’t open it too soon, as there’s a risk of pressure leaks. To avoid the fuel frothing, keep the tank group as upright as you can when opening the pressure tank valve. Make sure to turn the valve handle all the way counterclockwise. The fuel hose will stiffen when the pressure tank valve is opened.

Firers and assistants should practice often in different conditions to get better at judging distances. The firers should learn to get as close as possible to the target and fire at point-blank range whenever they can for the best results.

a. Point-blank range.

(1) Effects. At point-blank range, nearly all of the burning fuel can be shot at high speed directly through ports and openings into the target. This results in maximum casualties and damage to the hostile position.

(2) Safety. Basic safety measures are taken to avoid injuries to friendly personnel from potential ricochets or flames bouncing back. If the target is a vertical wall positioned at a right angle to the shooter or other friendly personnel, the weapon should not be fired from less than 7 to 10 yards away. When shooting at small openings in a bunker or pillbox, the shooter and other members of the assault squad should stay at least 7 to 10 yards away from the target.

b. Other useful ranges.

(1) Open fire zones. When using thickened gasoline, portable flamethrowers can be effective at distances of up to 40 yards under normal conditions, depending on wind direction and speed. In the same conditions, liquid fuel may be effective at 20 yards. The results and accuracy aren't as good as they are at point-blank range.

(2) Jungle or thick undergrowth. If the target is in jungle or dense underbrush without clear fields of fire, the effective range of the flamethrower is cut by as much as half, depending on the type and thickness of the vegetation.

c. Ineffective areas. Even though the flame can extend much farther than the distances mentioned in b (1) above, it might not be effective due to the sharp angle of descent and because a lot of the fuel is consumed before it hits the target.

Wind is a key factor due to the low speed of the burning fuel. Wind can extend, shorten, or change the direction of the flame.

a. Headwinds. Head winds over 5 miles per hour can push heat or even flames back toward the person firing. Liquid fuel shouldn't be fired into a head wind exceeding 5 miles per23hour. The range and accuracy of thickened fuels are decreased.

b. Light winds or gentle breezes. The best results come from these conditions.

c. Crosswinds. When shooting at or near maximum range, cross winds can shift, break apart, and spread out the flame. They also decrease the range.

a. Aim assist. The flamethrower can be operated from any position that allows enough freedom to aim the weapon, depending on the conditions in b, c, and d below. This includes standing, kneeling, and lying down. In some cases, flamethrowers have been fired while tank groups are resting on the ground or on skids. If used this way, the tops of the fuel tanks must be supported to meet the requirements in b below.

b. Tank angles. When firing, the bottoms of the fuel tanks must always be significantly lower than the tops. The tops of both tanks should also be at the same height above the horizontal, and neither tank should be leaning to one side. If this isn't maintained, only a small amount of fuel might be released from the tanks.

c. Rebound. The stability needs to be enough to handle the gun's recoil. If possible, the shooter should hold the gun tightly against their right side to support it and absorb the recoil.

d. Guardianship. Make the most of cover and concealment, like shell craters and plants.

a. Sighting. The gun has no sights due to the short distance from which it is fired, the different types of fuel used, and the significant impact of the wind. (Par 23)

b. Defensive structures. When shooting at a fortified position, flames should be aimed at the entrances (gun ports, firing slits, ventilation screens, doorways). Flames inside create the desired impact, but flames on the outside have minimal effect on the people inside.

c. Thick fuel. (Figs 3 and 20) When firing at or close to maximum range, it can take several seconds for a burst of thickened fuel to travel through the air to the target area. Short bursts might lead to misses at long range for this reason. Being skilled in aiming is especially crucial with thickened fuel.

d. Fuel. With liquid fuel, the best results can be achieved by directing the flame straight onto the target. (Fig 21)

24

25

With pressure tank valve open:

a. Pull the trigger. Pull the trigger quickly and forcefully. A flash should show up at the front of the gun. This indicates that an incendiary charge in the ignition cylinder has been lit. Let go of the trigger. (If the flash doesn’t show, pull the trigger 26 again, or as many times as needed up to five times, until a flash appears.)

b. Open fuel valve. Right after pulling the trigger, firmly compress the valve lever and grip the safety with your right hand. Burning fuel will be fired from the gun.

c. Adjust aim. Aim the burning fuel at the target. Keep squeezing the valve lever and hold the safety throughout the burst. When firing thickened fuel, watch the fuel from the side of the stream to see and adjust your aim. (If you look directly behind the stream, the flame might block your view of the target.)

To stop or pause firing, let go of the controls.

To fire more bursts, follow the steps in Paragraphs 26 and 27 again, remembering that there are five incendiary charges in the ignition cylinder and that the total firing time, excluding the time between bursts, is about 8 to 9 seconds. Each of the five incendiary charges in the ignition cylinder burns for 8 to 12 seconds.

When using liquid fuel, it might be a good idea to soak the target with fuel first and then ignite it. To do this, fire one or two short bursts without pulling the trigger. Then, follow up with an ignited burst, as mentioned in Paragraph 26.

When the shooter has come back from their mission, they should:

a. Take out and get rid of the ignition cylinder, like this:

(1) Aim the gun at the ground.

Press latch. (__A_TAG_PLACEHOLDER_0__)

(3) Unscrew the ignition shield and let the ignition cylinder drop out. (Make sure to keep your hands away from the front of the cylinder.)

(4) Keep the partially used cylinder for training purposes or dispose of it by firing from the gun after the fuel tanks have been emptied. For details on the care, handling, and storage of cylinders, see Paragraph 31.

b. Close the pressure tank valve by turning the valve handle to the right (to keep the remaining pressure in the pressure tank).

c. Aim the gun away from people and release any leftover fuel from the tanks by squeezing the valve lever and grip safety until nothing else comes out. Do not use the trigger during this process.

d. Remove the tank group from the back.

e. Examine, clean, and maintain the flamethrower (Pars 55 and27 56) or, if skilled maintenance staff is available, hand the weapon over to them for servicing.

f. After maintenance, put the weapon in the storage chest (Par 77) for safe keeping, or get it ready for the next mission. (Pars 50 through 53)

a. Description and functionality. (Figs 13 and 22) You can use either the M1 or E1 ignition cylinder. It fits over the front part of the barrel assembly and is rotated by the spring case. (Par 76) The five incendiary charges in the cylinder are spaced far enough apart in the plastic body to avoid igniting each other. Lead-foil seals, plastic closure plates, and waterproof cement ensure the unit is relatively waterproof.

b. Action. When the trigger rod is pushed forward, one of five metal matches tipped with red phosphorus scratches an igniting mixture. The ignition spreads to a starter mix and a few grains of black powder sitting on top of the incendiary charge. The black powder blasts the foil seal and closure plate off the flame thrower,28 and the incendiary charge ignites the fuel as it shoots out from the nozzle. The incendiary charge burns for 8 to 12 seconds.

c. Packing. Ignition cylinders come packed two per waterproof can. Each flamethrower includes three cans. Each packing box of extra cylinders contains fifty cans (100 ignition cylinders).

d. Care, handling, and storage. Ignition cylinders have dangerous flammable materials and should be treated with caution. The following safety measures should be followed.

(1) Opening cans. Only open cans with cylinders when you’re ready to load for a mission. (Par 18) If there’s an extra cylinder left in an opened can, use it right away. Any defective cylinders, like those with damaged closure plates, should be destroyed. (Pars 30 and 46) Moisture can affect the cylinders, so make sure to keep them away from dampness.

(2) Managing cylinders. Pressure on any of the five metal matches (Fig 13) could ignite an incendiary charge in the cylinder. Be careful not to apply pressure to the projecting ends of the matches except when firing the weapon. Ignition cylinders and their containers should be protected from shock. Boxes and cans with cylinders must not be tossed or dropped.

(3) Storage containers. Containers of ignition cylinders should be stored in a dry, well-ventilated area, away from direct sunlight, and adequately protected from extreme temperatures. Smoking is not allowed, and matches must not be used in areas where ignition cylinders are stored.

a. General. The pressure tank of the flamethrower must be fully charged with compressed air or compressed nitrogen before starting a mission. For the M2-2 flamethrower, a pressure of at least 1,700 pounds per square inch is required. This can be achieved either by using an air compressor that creates a pressure of at least 1,700 pounds per square inch or by using commercial cylinders. The filling and charging lines from the service kit are used with the cylinders. Before and after charging, follow the procedures described in Paragraphs 51 and 55.

b. Air compressor charging. The air compressor, powered by a gasoline engine and with a capacity of 7CFM, M1, is a self-contained, skid-mounted machine designed for use with flame throwers. It can charge the pressure tanks of flame throwers as well as large commercial cylinders of 200 or 220 cubic feet. You can find instructions for using the compressor in the manual that comes with it.

c. Charging from tanks. If you don’t have an air compressor available,29 you need to use cylinders filled with nitrogen or air.

(1) Pressure and volume. Cylinders are filled with 200 to 220 cubic feet of air or nitrogen. Because cylinders with 220 cubic feet of air or nitrogen have a higher initial pressure, it's advised to get those if they're available. All cylinders in use must have a pressure of at least 600 pounds per square inch. One or more of the cylinders must maintain a pressure of at least 1,800 pounds per square inch. It's best to use two or more cylinders, ideally at least four, if they are available.

(2) Charging capacity. Fully charged cylinders, when used correctly in rotation, can charge pressure tanks roughly as follows:

(3) Equipment. The setup for charging two pressure tanks using cylinders includes a filling line, two charging lines, and two cylinders. (Fig 23) The filling line and charging lines come from the service kit. (Par 48) Plugs are included to seal off one side of the filling line when only one flamethrower tank group needs charging.

(4) Alert. Oxygen is sometimes shipped in cylinders that have the same threads as nitrogen cylinders. If oxygen, which isn’t mixed with nitrogen like in air, is put into the fuel tanks of the portable flamethrower, it could cause a violent explosion. So, it’s extremely important to ensure that only air or nitrogen is used. Before connecting a cylinder, make sure to test it to ensure that it doesn’t contain pure oxygen or any flammable gas.. This can be done by putting a burning splint into a jet of the contents. Oxygen makes the splint burn rapidly, while nitrogen puts out the flame. To perform the test:

(a) Attach a thin wooden splint to a wire that's at least a foot long.

Light the splint.

(c) Step back and hold it in front of the cylinder outlet.

(d) Open the valve a bit to let a small stream of gas flow out.

(e) If the flame flares up, the gas is oxygen and MUST NOT be used.

(f) If the gas itself catches fire, it could be hydrogen, acetylene, or another flammable gas, which also should not be used.

(5) Connecting lines to cylinders. (Fig 23) To charge two flamethrower pressure tanks from two nitrogen or compressed air cylinders, start with the following procedure:

(a) Take off the valve-protection caps from the cylinders.

30

31

(b) Position the cylinders next to each other with both outlets pointing in the same direction. (If the ground isn’t level enough for the cylinders to stand upright, lay them down horizontally with both outlets facing up.)

(c) Before connecting the filling line to the cylinders, blow out any dust. (Par 33) Then attach them using wrenches to ensure the joints are airtight. Avoid kinking or bending the flexible hose. The cylinders should be positioned close enough to each other to avoid putting strain on the flexible hose.

(d) Connect a charging line to each of the two fittings on the filling line.

(6) Connecting charging lines to pressure tanks.

Close pressure tank valves.

(b) Remove the caps from the check valves.

(c) Attach the charging-line fittings to the check valves.

Close bleeding.

(7) Charging. The process of charging two pressure tanks from two cylinders works like this:

Close both fill-line valves.

Open cylinder valves.

(c) Identify which cylinder has the lower pressure using the gauges. Open the filling-line valve at the gauge displaying the lower pressure and fill the pressure tanks to the pressure indicated by the gauge. Close the valve. Next, 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 indicated by the gauge.

(d) When the pressure tanks are full, 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 the bleeders. Remove the charging-line fittings from the check valves. Screw the threaded caps onto the check valves and tighten the caps with a wrench.

(e) Repeat the steps in (a) through (d) above for all the pairs of empty flame-thrower tanks that need to be charged.

(8) To ensure correct pressure. Care should be taken to make sure that the compression supplied to the flame-thrower pressure tank is a full 1,700 pounds per square inch.

(a) If a filling-line valve is leaking, use a wrench to tighten the packing nut on the valve.

(b) When the higher pressure displayed on the filling-line gauges is below 1,700 pounds per square inch, close the filling-line valve and the cylinder valve on the cylinder with the lower pressure. Remove and replace this cylinder with a fully charged one. Use chalk to mark the pressure on the withdrawn cylinder.

(9) After charging up. Once charging is finished:

(a) Close the filling-line valves. Check the pressure shown on each gauge and note the pressure on each cylinder using32 crayon, chalk, or pencil.

(b) Shut the valves on the cylinders.

(c) Take off the charging-line fittings from the check valves, put the threaded caps back on the check valves, and tighten the caps with a wrench.

(d) Take out the filling lines from the cylinders. Use two wrenches and be careful not to twist or kink the flexible hose. Support the lines while you’re doing this so that their entire weight isn’t hanging on the flexible hose during removal.

(10) Use of four-line stanzas. (Fig 24) The filling and charging lines found in two or more service kits can be combined for more efficient charging of multiple pressure tanks. Each service kit includes an extra flexible hose for connecting two filling lines. The charging procedure is similar to what was described earlier for the two-place line. Air or nitrogen should be taken first from the cylinder with the lowest pressure and last from the cylinder with the highest pressure. See a (2) above.

Personnel will get to know the following precautions:

a. Management. Always handle all cylinders and flamethrowers with care; don’t drop them and don’t expose them to shocks or hits. Keep the valve protection caps on securely when moving cylinders, unless you’re using the nitrogen or air.

33

b. Storage. Store all cylinders and charged flamethrowers or tank groups (Par 77) in either open or closed storage. They need to be shielded from moisture and excessive heat from direct sunlight or other heat sources. Don't store them near highly flammable materials or in areas where they could be hit by moving objects. Keep empty cylinders separate to prevent any mix-ups.

c. Team. Don’t try to use compressed gases unless you’ve been trained for it. Use gases only for their intended purposes.

d. Cylinder valves. Do not mess with the safety features in cylinder valves. If you can, use the correct replacement parts for safety features that need fixing. If those parts aren’t available, don’t try to use temporary solutions or non-standard parts.

e. Opening valves. Open the valves slowly and completely each time you transfer nitrogen or compressed air from a cylinder. If you're using a wrench, make sure it fits well and is ready for immediate use while you're releasing the compressed gas.

f. Threads. Make sure that the threads align before connecting. Some valves come with specific threads that need to match the threads of the equipment being connected.

g. Proper gear. Use gauges, regulators, hoses, pipes, and tubing that are specifically designed or recommended for the particular equipment or compressed gas.

h. Fix. Never try to modify or fix a cylinder.

i. Fire and sparks. Do not allow flames, sparks, or ignition from the flame thrower or any other source to come into contact with the hose.

j. Dusting off. Right before connecting an attachment to the pressure tank or cylinder valve, quickly open it to blow out any dust or dirt. Avoid standing in a position where gas or dirt could blow into your eyes or face. If the valve is hard to open, gradually apply more force.

k. Special gadgets. Do not try to use any special connections or equipment without getting the approval of a qualified expert.

l. Keeping valves shut. Keep the valve of each cylinder closed when its contents are not being released or let into the cylinder. This applies to all cylinders, whether they contain compressed gas or are empty.

Thickened fuels provide up to twice the range of liquid fuels. The flow of thickened fuel is relatively narrow. Most of the glue-like fuel sticks to and burns on or in the target for as long as 6 minutes. Liquid fuels, on the other hand, are mostly used up during flight to the target. If the positions of small openings in the target are known, the stream of thickened fuel can be aimed accurately so that most of the fuel enters directly into the openings. While it doesn't spill around corners like liquid fuel, thickened fuel strikes the target with enough force to bounce inside. It adheres to skin and clothing as it burns. It also has excellent incendiary effects. The initial flame and smoke are less from thickened fuel than from liquid fuel, but the reduced visibility, greater range, and much longer burn time of thickened fuel make up for its smaller screening effect. Liquid fuels are easier to pour during filling than thickened fuels.

a. Ingredients. Thickened fuels are made by combining U.S. Army fuel thickener with fuel.

(1) Thickening agent. U.S. Army thickener comes in sealed cans, with each can holding 5-1/4 pounds of the product.

(2) Gas and fuel oil. Gasoline is often used with a thickener, but a mix of gasoline and light fuel oil can also work well. The light fuel oil can be No. 1 fuel oil, No. 2 fuel oil, automotive diesel oil, or kerosene. These mixtures produce more heat and don’t create crusts. Except in hot climates, at least 75 percent of the mixture by weight or volume should be gasoline. (If you add too much light fuel oil, the fuel may separate into two layers.) In tropical areas, a thickened mix of 50 percent gasoline and 50 percent light fuel oil has shown good results, but storage properties are unknown. Another well-recommended mixture from field reports is 15 gallons of gasoline to 5 gallons of diesel fuel oil. Issue gasoline can be used, but gasolines containing alcohol that are sourced locally are not suitable.

b. Thickener to fuel ratio. It's recommended to use less thickener than before. A low thickener ratio creates a thickened fuel that has many of the qualities of liquid fuel. One can of thickener for every 20 U.S. gallons of gasoline, or a mix of gasoline and light fuel oil, produces good results. This equates to a 4.2 percent by weight mixture. Unless it’s hot out, a fuel mix with less than 3 percent thickener needs so much stirring that preparing it becomes impractical.

c. Gear. You'll need an open-head 55-gallon or 42-gallon drum and a makeshift wooden mixing paddle. You can also use five-gallon cans to move the ingredients around. The paddle should be about 5 feet long, 2 inches wide, and 1 inch thick. If you're using a standard 55-gallon, open-head drum with an internal diameter of 27-7/16 inches, the makeshift paddle should be marked to show the gallon measurements like this:

35 Avoid using a metal paddle as it can create sparks from the drum. Never use galvanized containers for mixing or storing thickened fuels, as this can lead to the fuel breaking down and becoming too thin. An improvised funnel can be useful for filling drums with prepared fuel for aging or transport.

d. Temps.

(1) Below 50°F. If the temperature is below 50 degrees Fahrenheit, it's a good idea to prepare thickened fuel indoors, in a warm room. All safety precautions should be followed closely. (Par 40)

(2) Over 90 degrees. When the fuel is warmer than 90 degrees Fahrenheit, the thickener reacts very quickly. In this case, it's easier to create batches of 20 gallons each, but you can prepare as many batches as needed in a row.

e. Humidity.

(1) Moisture impact. Water in thickened fuel breaks down or lowers the thickness of the gel, which in turn reduces the range of the flamethrower. This effect might not be immediately apparent, but it impacts the stability of the fuel.

(2) Thickener dryness. Dry thickener is very hygroscopic, meaning it quickly absorbs moisture from the air. Because of this, thickener is packaged in airtight tin cans that hold the precise amount of powder needed to mix with 20 gallons of fuel to create a 4.2 percent mixture. It's crucial to measure out the gasoline or fuel oil before opening the thickener container. After that, the powder should be poured directly into the liquid right away.

(3) Container dryness. It's crucial that all containers used for mixing and handling the fuel are dry.

(4) Preventing water contamination in gasoline. Gasoline, especially if it's been stored in vented containers, often contains free water. So, when using gasoline from a bulk storage tank or an open drum, first pour it into a clean, dry drum; let it sit undisturbed for at least an hour; then carefully pour the gasoline off the top, discarding the last gallon or two.

f. Mixing and stirring. (Fig 25) The liquid fuel is poured into the open drum; a bucket or a paddle (Par 35 c) is used for measuring. One person then stirs the fuel vigorously. Another takes a can of thickener, cuts it open with a machete, bayonet, or ax, and immediately pours it into the fuel. Any large clumps of powder are broken apart by hand before the powder is added to the fuel. When mixing 40 gallons at once, both cans of thickener should be opened and added to the fuel quickly. If the first can is allowed to thicken before adding the second can, it will be hard to achieve a consistent mix. Keep stirring.

36

g. Checking the gas. Quickly lift the paddle. If the mixture falls off or drips from the paddle, keep stirring. When the paddle comes out clean, except for a thin layer sticking to it, you can stop stirring, as long as you don’t see any more settling of thickener particles. 37

h. Loading shipping barrels. Once stirring is done, the mix is quickly poured (Fig 26) through a funnel into the shipping drum. The second bung hole should be open, if possible, to allow air to help with the pouring. Two people handle the pouring, each taking one bucket so that the funnel stays loaded with the mix and the shipping drum gets filled as fast as possible. Finally, the open-end drum should be lifted and its contents poured into the funnel. No more than 50 gallons of thickened fuel should go into a 55-gallon drum. The funnel should then be removed and replaced with a plug. The vent opening of the drum should also be sealed. (See Paragraph 39 for the pressure method of filling storage drums.)

i. Extra thickener. Any thickener left in opened cans should be thrown away. Because moisture in the air can quickly damage its quality, don’t try to save it.

j. Aging and storage. Newly mixed fuel looks like tapioca pudding. (Fig 27) It’s best to store it overnight before use, but it can be fired within 1 hour after mixing. To keep the fuel in good shape, the drums used for shipping and storage must be clean, waterproof, dry, sturdy, and free from rust, but not galvanized. They should be kept tightly closed and stored on their sides to prevent rainwater from collecting around the bungs.

k. Fuel testing. Before using fuels on missions, all fuels should be tested by firing them from a flamethrower. This is recommended because the properties of the fuel ingredients can often differ.

38

a. Ingredient selection. Thin fuels ignite easily, but they have limited range and often burn up during the flight before hitting the target. For this reason, liquid fuels should have the lowest amount of gasoline and the highest amount of heavier oils that still allow for easy ignition. In hot climates, you need less gasoline compared to cold climates. However, getting the exact proportions isn’t critical. Suitable blends are as follows:

(1) Equal amounts by weight or by volume of gasoline, light fuel oil, and heavy (bunker) fuel oil. The light fuel oil can be No. 1 fuel oil, No. 2 fuel oil, automotive diesel oil, or kerosene.

(2) One part gasoline to four parts of cleaned crankcase drainings. (Par 36e) Unused motor oil can be used instead of crankcase drainings, but it’s usually not available for flame-thrower use.

b. Ingredient prep. Before mixing ingredients, follow these steps:

(1) Gasoline, diesel fuel, and heating oils. These fuels should be let to sit undisturbed for at least 30 minutes so that any small amount of water can settle at the bottom. When pouring the fuel into another container, do so gently to avoid mixing any water back in.

(2) Crankcase oil drain. If possible, let crankcase drainings sit in a container for at least 1 day. When pouring, be careful not to transfer any sludge that may have settled at the bottom of the container.

c. Gear. You'll need an open-head 55-gallon or 42-gallon drum and a wooden mixing paddle that you can make yourself. The paddle should be about 5 feet long, 2 inches wide, and 1 inch thick. Avoid using a metal paddle since it can create sparks when it hits the drum. You can also use 5-gallon cans for measuring and moving ingredients. Make sure to have clean, unrusted steel storage drums available. They should be at least 16-gauge to be strong enough to handle the internal vapor pressure of the fuel.

d. Stirring up. Mix all the ingredients in the drum with the paddle until they look like a consistent mixture. This should take about 2 minutes.

e. Engine oil blends. If crankcase drainings are used as an ingredient (Par 36b), it's best to let the prepared mixture sit for 24 hours after stirring, since the gasoline in the mixture might cause extra sludge to settle. Even after this settling time, it's advised to pour the mixture through cheesecloth or a similar fabric before filling the flame thrower. Crankcase-draining blends should only remain in the flame thrower long enough to complete a mission, as any additional sludge that forms from sitting will clog the weapon.

39

f. Transferring. The mixture should be transferred either directly into the flame-thrower fuel tanks (Pars 37 through 40) or into storage drums. (Par 35h)

g. Emergency fuel tank mixing. In an emergency, you can mix in the flame-thrower fuel tanks by adding the ingredients in the right amounts and then shaking or stirring.

h. Fuel testing. Before fuel is used on a mission, it should be tested, if possible, by being shot from a flame thrower.

i. Storage. Fuels can be used right after they are prepared. If the blend includes crankcase oils, it should be used as soon as possible after filling. Other liquid blends can be stored indefinitely until needed. For storage precautions, see Paragraph 40. The storage drums should also remain tightly closed to prevent gasoline from evaporating and to keep moisture out of the fuel. If stored outdoors, the drums should be placed on their sides to avoid rainwater collecting around the openings. A non-rusted and undamaged 16-gauge or 18-gauge drum has enough strength to handle the internal vapor pressure of the fuel.

(Fig 28) This method is the easiest and fastest for liquid fuel,40 but it might be too slow for some thicker fuels. The process is as follows:

a. Place the tank group on the ground or on a platform. If the tank group isn't connected to the gun group, secure the coupling plug in the tank coupling. (Par 70)

b. Use a 1-3/4-inch wrench to unscrew the filling plug and the safety-head plug.

c. Check the inside of tanks to ensure they are clean and free from debris. If they're not clean, rinse them with gasoline.

d. Using a makeshift funnel, fill to within 2 inches of the top of both plug openings. This creates enough space. The tanks will then hold about 4 gallons of fuel.

e. Clean the fuel-tank plug seats and the plug threads with a clean, dry cloth. (Fig 29) If the plug tends to freeze in place, apply some lubricant (Par 49 b) before screwing in the filling and safety-head plug assemblies. Tighten using a wrench.

f. Clean up any spilled fuel from the weapon.

A force pump, if available, can be installed with a short length of pipe in the top opening of a drum of fuel to fill flame-thrower fuel tanks. Keep the working parts of the pump clean.

Thickened fuel can easily be pumped into flame thrower tanks using very low pressures of compressed air or nitrogen. You can use the flame thrower fuel filling kit E6 or an equivalent. When the proper equipment is available, blowing the fuel in is more efficient for filling multiple flame throwers with thickened fuel. Pouring or pumping takes more time, depending on the gel's consistency. This consistency can vary between batches, even when using the same amount of thickener. The moisture content in the fuel seems to cause this variation. The precautions listed in Paragraph 40 should be followed.

41

a. Pressure source. When the pressure in cylinders of compressed air or nitrogen drops too low to fill pressure tanks for flame throwers, any remaining pressure42 can be used to blow fuel into fuel tanks, as long as the regulator valve can lower the pressure to 20 pounds per square inch. For safety precautions, see Paragraph 33. An air compressor or a hand pump (like a tire pump) can be used instead of a cylinder if one isn’t available. The pressure applied to the fuel drums should be no more than 15 to 20 pounds per square inch. Only a diaphragm-type regulator valve should be used safely. This valve must be able to manage any pressure that’s applied to it.

b. Drum set. Use clean, non-corroded, steel 55-gallon drums. Drums made in the United States that meet requirements will have the ICC-5 or ICC-5A stamp, followed by three sequential numbers, for example, “14-55-44.” The number “14” represents the gauge of the metal; “55” refers to the capacity in gallons; and “44” signifies the year of manufacture. A steel drum with a gauge of 14 or heavier is preferred, but lighter drums (16 or 18 gauge) may be used. Drums with gauges lighter than 18 (20 or 22 gauge) must not be used. Drums should never be moved while they are under pressure.

c. Connections. The pressure source (see a above), the fuel drum, the fuel-filling line, the air hose, and other components are connected as shown in Figure 30. Threaded adapters are used where needed to attach lines to the drum. All threaded connections should be tightened using wrenches on the joints. The drum and the pressure cylinder (if used) should be positioned on their sides on the ground or a platform. The opening of the drum connected to the fuel-filling hose should be close to the ground or platform. If the tank group is filled without the gun group, insert the lock coupling plug (Par 70) in the tank coupling.

d. Procedure. To refuel:

(1) Take out both the filling and safety-head plugs.

(2) Check the inside of the tanks to ensure they are clean and free of any debris. If they aren't clean, flush them with gasoline.

(3) Put the end of the fuel-filling hose into either of the two fuel tank plug holes, using a nipple as a spout.

(4) Start the air compressor or pump, or open the valve on the cylinder of compressed air or nitrogen. Open the regulator valve on the filling line by turning the handle slowly until the gauge shows 15 to 20 pounds of pressure, but not more. Warning: “Cracking,” or opening a cylinder valve without using the proper regulator valve (Par 39 a), can cause explosive pressure in the drums.

(5) Both tanks need to be filled to within 2 inches of the top. Shut off the valve on the fuel-filling hose to stop the flow at this level.

(6) If no more flame throwers need to be filled, close the pressure-cylinder valve, or turn off the compressor or pump. Then, using a wrench, slightly loosen the air line at the drum to let the pressure bleed out. Once the pressure in the drum has dropped to atmospheric level, close the regulator valve.

43

(7) Slowly and gently roll the drum until the fuel-filling hose is at the top of the drum.

(8) If there are valves at each end of the fuel-filling hose, use a wrench to slightly loosen the hose, allowing pressure to escape gradually. Stand to the side of the connection and keep the hose pointed away from other people. Once all the pressure has been released, finish unscrewing the hose.

(9) Clean the fuel-tank plug seats and the plug threads with a clean, dry cloth. Then screw in the filling plug and safety-head plug assemblies, using grease (Par 49 b) if the plug tends to stick to the seat. Tighten with a wrench. Wipe up any spilled fuel from the weapon.

a. Fire risk. All fuels used in flamethrowers are clearly very flammable and must be handled, stored, and used with great caution. Diesel, fuel oil, and kerosene need to be treated with the same care as gasoline.

b. Indoor storage. If you need to handle gasoline indoors, make sure to keep the windows and doors open and ensure that there are no open flames nearby that could ignite the fumes. Leave the doors and windows open long enough afterward for any gas vapors to dissipate.

c. Fire and sparks. Open flames, hot stoves, electrical tools and equipment, and anything else that could cause sparks are not allowed. Even nails and metal cleats in shoes can be a risk when there are flammable fumes around.

d. Vaping. "No Smoking" signs should be displayed in visible locations throughout the property, and the no smoking policy must be strictly enforced.

e. Airflow and cleaning. The buildings where fuel is stored or used must be properly ventilated and cleaned thoroughly every day. No trash or other flammable materials should be allowed to stay in or near those buildings.

f. Spill. Care should be taken to avoid spilling fuel. Any spills should be cleaned up immediately.

g. Safety containers. Whenever possible, use safety cans to store small amounts of gasoline because they have lids that need to be held open tightly to add or remove gasoline.

h. Clothes. Metal containers with metal lids should be supplied for thrown-out, oily, or gasoline-soaked rags. These rags need to be thrown away every day.

i. Electrical devices. Use vaporproof incandescent light bulbs, switches, and other approved devices. Avoid using open switches, relays, and similar equipment, or motors with commutators, in areas where gasoline fumes might be present.

44

j. Hose. Flexible metal, rubber, and rubber-metal hoses should be checked regularly (at least four times a year) and thrown away when they show clear signs of wear.

k. Hazardous fumes. Gasoline fumes are somewhat harmful and shouldn’t be inhaled.

l. Leaks. Leaks should never be ignored, and we must always remember that gasoline is a hazardous liquid. Inspections for leaks should be conducted regularly, especially at the joints of pipes and hoses.

m. Fire extinguishers. Carbon tetrachloride, carbon dioxide, or foam fire extinguishers should be available and located where they can be easily accessed in case of a fire. If there are no suitable extinguishers available, sand, not water, should be used on burning fuel.

n. Unleaded gasoline. Gasoline usually has a toxic lead compound in it. This type of gasoline, or fuel that has leaded gasoline, shouldn't come into contact with the skin, particularly the lips, eyes, open cuts, and sores.

The M2-2 flamethrower can be handled and fired effectively in the rain or even after brief immersion in water. After use when it's wet, it should be dried to prevent rust, cleaned, and lubricated. (Pars 49 and 55) Any areas where the paint has chipped should be repainted with fresh paint. The weapon should be stored in a dry location. Moisture must not be allowed to enter the fuel, fuel components, or ignition cylinder containers.

Keep all dust, dirt, and mud away from the flamethrower; particles can disrupt the functioning of the spring case, valves, bearings, and pressure regulator. Store weapons and extra gear in closed chests and boxes when not in use. (Par 77) Clean before use. (Pars 51 and 52)

A hot climate or exposure to the sun makes fuel thinner when it's in containers. Thinner fuel has a shorter range; it gets used up quickly in the air before reaching the usual effective distances. In extremely hot areas, less gasoline or other thinning agents should be included in a fuel blend than usual. (Pars 34 through 36)

45

Cold weather decreases the overall heat produced during a firing mission, but not usually enough to significantly impact its effectiveness. The incendiary effects might be reduced since materials are less flammable in cold conditions. The weapon can be used at temperatures as low as minus 20 degrees Fahrenheit. To enhance ignition, use more gasoline in the fuel than usual. (Pars 34 through 36)

Flame throwers shouldn't be used in strong headwinds or strong crosswinds. (Par 23)

If circumstances require leaving behind chemical warfare materials in the field, they should be destroyed or made useless to prevent the enemy from using or studying them. The following methods are recommended:

a. Flamethrower. Shooting one or more small-arms bullets into the fuel tanks will make the flame thrower unusable right away. Additional shots can be fired at the pressure tank. If the pressure tank is pressurized, open the pressure-tank valve for a few seconds to allow the contents to escape. This is important if shots are to be fired at close range. You can render the gun useless by bending it over a hard surface. A sledgehammer or axe will destroy valves and tubes. A fragmentation grenade will also do the trick.

b. Filling and charging equipment. The flexible hoses, gauges, and valves can be damaged by hits from an axe, sledgehammer, or other heavy tool. The large pressure cylinders become useless if you release their contents and then damage the valves with strikes from an axe or sledgehammer. Cylinders can be stacked like firewood in groups of five and taken out by detonating four 1/2-pound blocks (2 pounds) of TNT in the middle. The air compressor can be destroyed using a similar method.

Fuel. Burn.

d. Mixing equipment. Containers and filling lines can be damaged by axe or hammer strikes, or by gunfire.

e. Thickener. Cans of thickener should be opened. The contents should be thrown into a fire or into water.

f. Ignition keys. Burn to destroy. Staff should stay several yards away from the fire because the cylinders can ignite with a minor explosion.

46

Part Three provides guidance for the staff of the using organizations in charge of maintaining this equipment (1st and 2nd echelon). It includes the necessary information for carrying out scheduled lubrication and preventive maintenance services, as well as descriptions of the key systems and units and how they function in relation to other components of the equipment.

One service kit for the portable flame thrower M2-2 will be provided for every six M2-2 portable flame throwers. The kit contains tools, equipment, and spare parts for second echelon maintenance and for pressure tank charging. Adjustable wrenches may be included instead of the plain-end wrenches listed. The numbers associated with items are Chemical Warfare Service stock numbers. The approximate contents are as follows:

a. Tools.

1 Screwdriver, cabinet, 4.5-inch blade length, 0.19-inch blade diameter, H22-50-13. (Fig 8)

1 Screwdriver, standard, 6-inch blade length, 5/16-inch blade diameter, H22-50-6. (Fig 8)

2 Wrenches, hex, 3/16 inch across flats (for 3/8-inch socket-head set screws), H22-49-91.

2 Wrenches, hex, 1/8 inch across flats (for 1/4-inch socket-head set screws), H22-49-12. (Fig 8)

47

1 Wrench, valve-adjusting, assembly A81-6-48. (Fig 8)

1 Wrench, heavy “S”, 1-3/8-inch and 1-1/2-inch openings, approximately 12 inches long, H22-49-113. (Fig 8)

1 Wrench, engineers’, double head, 3/4-inch and 7/8-inch openings, approx 9 inches long, H22-49-115. (Fig 8)

1 Wrench, heavy “S”, 1-3/8-inch and 1-3/4-inch openings, 12 inches approx length, A81-6-49. (Fig 8)

1 Wrench, engineers’, single head, 1-1/8-inch opening, 10-1/2 inches approx length, H22-49-31. (Fig 8)

1 Wrench, adjustable, single end, approximately 6 inches long (crescent-type), H22-49-67. (Fig 8)

b. Accessories and spare parts.

1 Line, filling, pressure cylinder, assembly C81-3-4. (Fig 23)

1 Hose, flexible, assembly E81-3-6. (Fig 24)

2 Lines, charging, pressure cylinder, assembly B81-3-29. (Fig 23)

1 Tank and valve, pressure, assembly (without shaft and handle) B81-1-374. (Fig 33)

1 Shaft, flexible, valve, assembly E81-1-470. (Fig 33)

1 Handle, valve, A81-1-473. (__A_TAG_PLACEHOLDER_0__)

1 Nut, machine screw, hex, 5/16-inch, 24NF-2, H22-93-55. (Fig 33)

2 Case, spring, assemblies B81-1-444. (Fig 9)

2 Diaphragm, valve, assemblies A81-1-416. (Fig 9)

1 Hose, fuel, flamethrower, M1, assembly B81-1-498. (Fig 48)

2 Plugs, coupling, E81-1-514. (__A_TAG_PLACEHOLDER_0__)

6 Heads, safety, R81-1-561. (__A_TAG_PLACEHOLDER_0__)

1 Gage, fuel tank testing, assembly E81-6-57. (This assembly includes a plug that is drilled, tapped, and fitted with a 0-500-pound pressure gauge.)

3 Washers, coupling, A81-1-513. (__A_TAG_PLACEHOLDER_0__)

2 Cord, cotton, seine, No. 4 hard braided, mildew-resistant, O.D., (1/8-inch diameter by 25-foot skeins), H100-4-5.

6 Bushings, pipe, head, 3/4 inch by 1/2 inch, (galvanized iron), H98-5-93. (Fig 9)

1 Regulator, pressure, assembly B81-1-438. (Figs 33 and 37)

1 Compound, anti-seize, white lead base, (for threaded fittings) 1/4-pound can, H99-3-12.

2 Gages, pressure cylinder testing, assembly B81-6-90. (Fig 32)

1 Catalog CW7-440114, Army Service Forces, “Portable Flame Thrower M2-2.”

1 Technical Manual 3-376A, “Portable Flame Thrower M2-2.”

48

49

a. Gun lobby. War Department Lubrication Order No. 4001 (Fig 31) outlines the parts that need lubrication, the types of lubricants to use, and the recommended intervals for application.

(1) Lubes. Use general purpose grease No. 1, except when temperatures are below freezing, in which case use general purpose grease No. 0. The bearing surfaces should be lightly coated with the grease.

(2) Lubrication frequency. The surfaces of the ignition-head body that come into contact with the spring case should be lubricated after each use of the weapon. Other parts should be lubricated after every six firing sessions, six training sessions, or more frequently if needed. Everything should be thoroughly cleaned (Pars 52, 55, and 56) with gasoline, dry cleaning solvent, or another suitable solvent, and then dried before lubrication. If the gun is taken apart for any other reason, it should be lubricated before being reassembled.

(3) Records. To check when six missions have been launched, a record of firing (Par 2) should be maintained with each flamethrower.

b. Armored unit. The tank group usually doesn’t need lubrication. However, it may need it under these exceptional circumstances:

(1) If the tank group has been submerged in water for several hours, the flexible shaft of the pressure valve may have lost its lubricant. If that's the case, remove the shaft (Par 66 b) and check it. If there's no lubricant, as shown by it being hard to move after removal, dip the shaft in a solvent to clean it and then coat it in warmed general-purpose grease, No. 1. Reinsert the shaft into the valve.

(2) If filling or safety-head plugs (Figs 39 and 40) tend to stick to fuel tanks, apply general-purpose grease, No. 1 (No. 0 if it's below freezing) before replacing the plugs.

Preventive maintenance services, as outlined by Army Regulations, are a responsibility of the organizational levels of maintenance. These services include:

50

a. Before, during, and after the operation, services provided by the shooters and their assistants.

b. Scheduled services done by maintenance staff of the organization (services during filling and charging, and services after six firing missions).

The following services need to be done before filling, charging, and loading the flame thrower with pressure, fuel, and the ignition cylinder:

a. Pressure tank valve. Open and close the pressure-tank valve to check how easily it operates.

b. Threaded connections. Inspect all threaded connections for tightness, using the right wrenches.

c. Tank connection. Check the coupling for cleanliness and smooth operation of the lock and cams. (Par 70) Clean it if needed. If the washer is damaged, replace it by using a screwdriver to pry it out.

d. Connections. Check the filling plug and safety-head plug to ensure all parts are complete (Par 69 a) and that the threads and seats are clean. Clean them with a cloth if needed. If the rod or rod and chain have broken off and fallen into the tank, turn the tank upside down and remove them. Take off the deflector tube from the head (use your hand, not a wrench). Inspect the diaphragm to see if it’s intact. If the diaphragm is damaged, replace the safety head with an undamaged one. (Par 69 b, c) Reassemble the plug, head, and deflector tube in the left fuel tank. (Fig 11) The tube should face to the rear and at a 45-degree angle towards the operator’s left shoulder. (Fig 18) Hand-screw the deflector tube in; do not use a wrench on it. Tighten the lock nut with a wrench.

e. Pressure tank clamp. The clamp should secure the pressure tank firmly in place. If the tank is loose, a wooden splint or wedge under the clamp can be used as a temporary fix.

f. Carrier-frame bolts. Check if they're tight. Use a wrench.

g. Carrier. (Par 71) Check all canvas, webbing, and cord for any signs of mold, rot, or damage. Replace any defective parts. If you find mildew, move the flame thrower to storage in the dryer.

h. Rope (lashing). Check for tightness. If needed, make it tighter and use secure, non-slip knots. When the tank group is filled with fuel and positioned on the firer, its weight should primarily be supported by the canvas and webbing, not by the metal frame.

i. Shoulder and body straps. Adjust the straps to fit the shooter. (Pars 19 and 71) A loose tank group can lead to discomfort or injury when the wearer shifts positions during a mission. Check that the two pins and two cotter pins securing the shoulder straps to the steel support are present and in good condition. Inspect the fasteners.

The following services need to be done before filling, charging, and pressurizing the fuel and ignition cylinder:

51

a. Tank end hose connector. Check to ensure the nipple is clean and not heavily damaged. If it’s too damaged, the nipple might not create a tight seal at the tank coupling, which could lead to leaks and a loss of pressure. Refer to Paragraph 73 d for nipple repair.

b. Fuel line. Check the surface of the hose for cracks or other signs of wear. Pay special attention to the areas near the gun and tank coupling, which experience a lot of bending. If the hose is damaged, replace it. (Par 73 b, c) Do not attempt to patch it.

c. Hose connector, gun end. Check the tightness of the threaded connection between the hose and the fuel valve body by using your hand or applying very light pressure with a wrench.

d. Shield. Take off the ignition shield. Check the threads on the shield and the ignition-head body for cleanliness. If they’re dirty, use a cloth to clean them. When putting it back together (Par 18 c), the shield should rotate smoothly until it locks in the right position.

e. Valve handle and needle.

(1) There should be some slight give in the valve lever. To test it, remove the ignition shield. Squeeze the grip safety and valve lever slowly, watching the movement of the valve needle. The valve lever should move about 1/16 inch before the needle starts to move.

(2) The valve needle should be securely seated in the barrel nozzle. After pulling back the valve lever and releasing it, there should be no movement in the needle. For needle adjustment, see Paragraph 75 d.

f. Screws. Use a screwdriver to check the tightness of all screws.

g. Spring retainer and plug. Check the tightness of the spring retainer and plug (Fig 47) by using your hand or applying very light pressure with a wrench.

h. Ignition cap. All visible surfaces of the shield, nozzle, needle, and other parts of the ignition head, or those nearby, should be clean. If they're not, use a cloth.

i. Atomizer vent. With the fuel valve fully open, insert a fine wire into the atomizer hole of the nozzle to clean it out. Then, use a cloth-wrapped stick to clear any debris from inside the nozzle that was pushed through the atomizer hole. If this debris isn't removed, it could prevent the fuel valve needle from sealing properly at the nozzle. Repeat the procedure in e (2) above.

j. Spring collection. The spring case should move easily on the ignition head. If it doesn't, wipe away any grease or dirt from the surfaces with a cloth and apply new lubricant. (Par 49)

k. Trigger. Pull the trigger once or twice to see if it functions smoothly and returns to its original position. If it doesn't, clean and lubricate the trigger. (Par 49) Check the condition of the trigger spring.

l. Trigger bar. Check the position of the trigger rod when the trigger is pulled all the way back, as if you were firing. The rod should extend about 1/16 inch beyond the end of the lug in the ignition head. If it doesn't, bend the rod slightly, switch the position of the bearing, or replace any worn parts.

52

a. Fuel tank inspection. Right before filling and charging, take out the plugs (Par 69 b) and check the inside of the fuel tanks to make sure they are clean and free from debris. If they’re not clean, rinse them with gasoline until they are.

b. Fuel status. When filling (Pars 37 through 40), make sure that the fuel reaches the same level in both tanks. If they don't level out, the tank connector may be blocked with debris. If that's the case, clean it as described in a, above. After filling, wipe the plug seats with a cloth before putting the plugs back in. Clean up any spilled fuel from the weapon.

c. Pressure tank valve. Before filling the tank group with air or nitrogen, manually open and close the pressure-tank valve a few times to ensure it works smoothly. If it doesn’t, adjust it as explained in Paragraph 66 d.

d. Testing for leaks in the pressure system. After charging, and as few hours as possible before a mission, use a 0-3,000-pound gauge provided in the service kit to test the pressure. (Fig 32) To install the gauge, unscrew the check-valve cap and screw the gauge into the check-valve body. If the pressure has dropped below the level to which the tank was charged (Par 32), a leak is indicated. Remove the gauge, replace the check-valve cap, and check for leaks at the joints between the pressure tank and valve, and between the tank valve and check valve. (A wrench should be used to tighten the cap on the check-valve body to prevent creating an additional leak.) Large leaks can be felt or heard. Small leaks can be detected by applying a soap-and-water solution to the joints. Bubbles indicate leaks. If a leak is found between the pressure tank and the pressure-tank valve, or between the check valve and the pressure-tank valve, replace all three as a unit. If tests do not reveal the leak, the tank may have been improperly charged. It should be recharged and then retested.

a. Failed to ignite. Keep pulling the trigger. If the ignition cylinder still doesn't work, there might be dirt stuck in the ignition head. Unscrew the shield halfway. Screw it back on while tapping the shield with your hand. This should help get rid of any debris. Pull the trigger again. Do this again if needed.

b. Safety helmet "breaks". If the safety head breaks, the firing mission can't be executed. After returning, replace the head. (Par 69) Follow the testing procedure. (Par 56 b)

a. Unloading goods. Take out the ignition cylinder (Par 30), close the pressure tank valve, and blow out any leftover fuel and pressure. (Par 30)

b. Equipment removal. Unbuckle the body straps, then the shoulder straps. If you're lying down, shift to your side and let the tank group roll off onto the ground. If you're standing or kneeling, be careful that the tank group doesn't fall on your feet or legs.

c. Reporting or fixing. Fix any issues or problems or let the service or maintenance team know about them as soon as you can.

d. Firearm. Take off the shield (Par 18) and wipe down the inside of the shield with a cloth. Clean the holes in the shield with a wire or wooden stick. Clean the outside of the barrel, nozzle, needle, and other components. Check the cleanliness and proper alignment of the needle. (Par 75 d) Test the trigger to ensure it works. Lubricate it. (Par 49)

e. Fuel tanks and corridors. Remove the plugs (Par 69 b). Drain any leftover fuel. Use gasoline to clean out any thickened fuel residues before they harden and block the passages. If needed, fill the tanks with gasoline and let them sit for a few hours, shaking them occasionally. Drain and repeat if necessary.

f. Safety manager. Inspect the head to see if it’s damaged; if it is, replace it. (Par 69) Follow the testing procedure. (Par 56 b)

g. Pressure tank valve. If the weapon is going to be stored, open the pressure-tank valve and keep it open until the next time it needs to be charged.

h. Carrier. Clean, if needed, with soap and water, or gasoline.

i. Exterior metal surfaces. Clean exterior metal surfaces of fuel to avoid fire hazards. Let them dry before using again.

j. General check. Thoroughly check all other parts, make adjustments where needed, and replace any that are damaged.

54

After the flamethrower has been used in six firing missions or the equivalent in training, experienced personnel should follow these instructions:

a. Pre-op and post-op service. Follow the same procedures as in Paragraphs 52, 53, and 55.

b. Test firing (or simulated firing).

(1) If the situation allows for test firing at an appropriate test range (Par 15), fill the fuel tanks with fuel. (Pars 37 through 40)

(2) If testing with fuel isn't possible, fill the fuel tanks with clean water. (Make sure to dry all parts after testing.)

(3) Remove the filling-plug assembly. (Par 69) Use a bent wire to pull out the retainer rod and chain.

(4) Don't unscrew the safety-head plug.

(5) Insert the testing plug with a 0-to-500-pound pressure gauge (the plug and gauge are from the service kit) into the filling-plug opening. Secure the testing plug in place with a wrench.

(6) Completely fill the pressure tank. (Par 32)

(7) If you're test firing with fuel, load the ignition cylinder. (Par 18)

(8) Open the pressure-tank valve and at the same time check the pressure in the fuel tanks by looking at the gauge. The gauge shows the pressure in both tanks. It should be between 350 and 390 pounds per square inch.

(9) Check the gauge after at least 5 minutes. The tanks should show a pressure reading of no more than 390 pounds. If the pressure keeps rising above 390 pounds and the safety head blows, replace the safety head and the pressure regulator.

(10) Fire by using the controls (or simulate firing if the tanks are filled with water). The burst should last for 3 seconds, during which the pressure should not drop below 260 pounds.

(11) If the pressure doesn't meet the requirements mentioned in (8), (9), and (10), adjust the pressure regulator up or down. (Par 67 d)

(12) While the test firing is happening, check for leaks at all joints and connections on the tank group. The pressure system should be tested by applying a soap-and-water solution to the joints and looking for bubbles that indicate leaks. For replacing parts with pressure leaks, see Paragraph 66. Fuel leaks can sometimes be noticed without using soap and water. For repairing fuel leaks, refer to Paragraph 75 e. The nozzle should be examined by removing the ignition shield. Nozzle leaks can be fixed by cleaning, adjusting the needle (Par 75 d), or regrinding. (Par 75 e) If this doesn't work, replace the needle and barrel together.

c. Fuel shutoff valve. Release all pressure from the gun by using the fuel valve. Gently take off the valve grip and grip support. (Par 74) Check for any signs of leaks at the valve diaphragm.55 If there is a leak, replace the valve-diaphragm assembly. (Pars 75 b and 75 c)

d. Valve handle. Take apart the valve grip (Par 74) and apply lubricant. (Par 49)

Tighten the carrier strap.

f. Gun interior. If thickened fuel has been fired, take apart the gun. Clean all parts of any dried fuel build-up. Lubricate (Par 49) and put it back together. If liquid fuel has been fired, rinse the gun with clean gasoline. Disassemble just enough to lubricate. Reassemble.

First, take out the ignition cylinder. Then, before taking apart, servicing, or fixing any parts that might be under pressure, make sure to relieve the pressure. Remove fuel if needed.

The tank group holds fuel and pressure. When the pressure-tank valve is opened, the fuel is put under pressure. The tank group is held on the firer’s back and shoulders by the carrier.

59

a. Description and functionality. The pressure tank and valve assembly (Fig 33) consists of:

(1) Pressure vessel. The pressure tank is a lightweight, airplane-style cylinder designed to handle the high pressure inside it. The tank is filled with air or nitrogen at a pressure of 1,700 to 2,100 pounds per square inch using additional equipment as detailed in Paragraphs 31 and 32. This pressure remains in the tank until the weapon is ready to fire. When the pressure-tank valve is opened, air or nitrogen is released through the pressure regulator to the fuel tanks. Oxygen or flammable gases are never used in the tank to avoid the risk of a violent explosion. The tank has a large capacity to ensure sufficient pressure and a full range for the entire load of fuel. The pressure-tank clamp (Fig 39), a steel strap with a hinge and toggle-type latch, secures the pressure tank in place on the fuel tanks.

(2) Pressure tank valve. (Figs 33 and 34) This valve is screwed into the bottom of the pressure tank. The valve stem slides into the end of the valve’s flexible shaft. When the valve handle and flexible shaft are used to open it, the valve allows compressed air or nitrogen to pass through tubes and the pressure regulator to the fuel tanks. The valve is of the quick-opening, packless, diaphragm type.

(3) Pressure valve handle and flexible shaft for the valve. (Figs 33 and 34) The pressure-valve handle is secured by a small nut at the end of the valve flexible shaft, which is connected to the pressure-tank valve via the valve stem and a large hex nut. The handle and shaft extend to the right of the tank group, allowing the user to open and close the valve independently while carrying the weapon. The handle fits over the end of the shaft and is attached with a nut. The shaft is secured to one of the fuel tanks using a clamp, nut, and bolt welded to the tank.

(4) Check valve. (Figs 33 through 35) The check valve works like the valve on a car tire, but it's much heavier and differently designed because the pressure in the flame thrower is 50 times greater than in a car tire. Attached by threads to the pressure valve, the check valve allows compressed air or nitrogen to flow into the pressure tank during charging (Pars 31 and 32) but stops it from escaping when the external pressure source is removed. The cap on the check valve is only taken off for charging or testing.

b. Removal. (Fig 33) To avoid damaging threads, causing leaks, and losing pressure and range, only remove the pressure tank and valve assembly when absolutely necessary.

60

(1) Letting Off Steam. Make sure all pressure has been released from the pressure system before taking apart or removing any part or assembly. To release pressure, operate the fuel valve (Par 26) and hold it open until61 the pressure is fully drained. As an extra precaution, people should avoid facing the connections when disconnecting parts or assemblies.

(2) Removal process. After all pressure has been released:

(a) Unfasten the clamp from the valve flexible shaft.

(b) Using a wrench, unscrew the large hex nut that secures the flexible shaft to the pressure-tank valve.

(c) Remove the flexible shaft and handle from the valve.

(d) Using a wrench, unscrew the flared tube nut on the regulator tube next to the pressure-tank valve.

(e) Open the pressure tank clamp (Fig 39) and swing the clamp strap outward.

(f) Take off the pressure tank along with the pressure-tank valve and check valve.

(g) To take off the valve handle, use an adjustable wrench to loosen and remove the nut from the threaded outer end of the valve's flexible shaft. Slide the valve handle off.

62

c. Setup. (Figs __A_TAG_PLACEHOLDER_0__ and __A_TAG_PLACEHOLDER_1__) To set up:

(1) Insert the pressure tank (with the pressure-tank valve and check valve attached to the tank) through the pressure-tank clamp. Make sure to align the regulator tube, elbow, and pressure-tank valve threads carefully so that they don’t get damaged while connecting.

Close the pressure tank clamp.

(3) Begin the threaded connections by hand to ensure they are properly aligned. Don't force anything. Use a wrench for the final tightening, but avoid applying excessive torque to the wrench.

(4) Insert the valve flexible shaft through the small clamp into the pressure tank valve. Use a wrench to tighten the large hex nut located between the shaft and the valve.

(5) Tighten the clamp on the valve's flexible shaft.