Operation in Extreme Heat - TM-5-4320-240-150028

handling of electrical wiring during extreme cold. Wiring

c. Fuel System. Take care to prevent the entry of

becomes brittle and is easily damaged and cracked.

dust and grit into the fuel system. Clean the fuel

Maintain the batteries at full charge to increase their

strainer and sediment bowl frequently. Take special

efficiency and lessen the possibility of damage due to

precautions to keep the air cleaner properly serviced.

extreme cold.

Experience will dictate the servicing interval required.

Caution: Run the engine for at least one hour

2-17. Operation Under Rainy or Humid Conditions

after adding water to battery electrolyte. This will

If the pumping unit is installed outdoors in conditions of

allow water and electrolyte to mix thoroughly and

high humidity, erect a shelter, if possible, to protect the

prevent freezing.

unit. If the erection of a shelter is not possible, cover

2-15. Operation in Extreme Heat

the unit with a tarpaulin or other vapor-barrier material

when the pumping unit is inoperative. During dry

a. General. Provide special servicing and take

periods, remove side panels to allow engine

necessary precautions when operating the pumping unit

components to dry. Maintain a full fuel level in the fuel

in extremely high temperatures. Provide adequate

tank to prevent the formation of condensation.

ventilation when operating the unit indoors.

2-18. Operation in Salt-Water Areas

b. Fuel System. Do not fill the fuel tank completely to

the top. Allow room for expansion of fuel as it heats to

a. Salt water has a highly corrosive effect on metals.

ambient temperatures.

Prevent contact of salt water with the unit whenever

possible. If unit is exposed to salt water, wash with

c. Lubrication. Lubricate the pumping units as

fresh water after every exposure.

directed in the lubrication order (LO 5-4320-240-12).

Caution: Never use salt water in the coolant

d. Coolant System. Maintain a sufficient supply of

system of the engine. This will cause extreme

coolant in the radiator at all times. Keep the cooling

corrosion and will greatly limit life of engine.

system free of rust and scale by using an approved rust

inhibitor. Make sure that the thermostat is providing

b. Take special precautions to keep the unit painted

proper temperature control of the engine coolant.

properly. Paint all exposed metal surfaces. Coat all

Check the fan belts for proper adjustment. Make sure

exposed polished metal surfaces with standard issue

that the radiator fins are free from dirt, corrosion,

rust proofing materials, if available, or apply a light coat

insects, and other matter that could reduce cooling

of grease. Refer to TM 9-213 for preservation and

efficiency. Adjust the fan belts (para 3-11).

painting instructions.

2-16. Operation in Dusty or Sandy Areas

2-19. Operation at High Altitudes

a. General. If the pumping unit is permanently

a. General. As altitudes increase, the thinning of the

installed, provide a protective shelter if possible. For

air decreases engine efficiency so that power output

temporary installation, take advantage of natural

drops approximately 31/2 percent for each 1,000 feet of

barriers to protect the unit as much as possible. Keep

elevation. Because of the reduced external pressures,

side panels and the instrument panel cover closed.

suction lifts decrease and pumping efficiency is also

Keep the unit free of sand and dirt,' taking special care

greatly reduced. Refer to table 2-2. For these reasons,

to keep radiator cores clean.

it is highly important to maintain all other systems at the

peak of efficiency to assure that all available power is

b. Lubrication. In sandy and dusty areas, service the

applied to the pump.

oil filter more frequently than directed in the lubrication

order. Clean all lubrication points before and after

b. Carburetor. Decreased air pressure at high

lubrication. Keep lubrication containers tightly sealed

altitudes upsets the calibration of the carburetor, causing

and stored in a dust-free area.

an excessively rich fuel-air mixture.

Adjust the

carburetor as directed in paragraph 3-32.

2-11