Section VI. OPERATION UNDER UNUSUAL CONDITIONS
65. Operation in Extreme Cold
(5) If possible, keep the fuel tank full when
operating in extreme cold weather. This
a. General.
Operating the lubricating unit in
will prevent condensation of moisture
extremely cold temperatures presents special problems.
inside the tank.
Lubrication, fuel, oil, electrical and compressed air
systems, and care of lubricants are all affected by cold
g. Air Cleaner. At subzero temperatures, do not
weather operation.
use oil in the air cleaner assembly (6, fig. 6) as it will
congeal and prevent the easy flow of air. Wash the
b. Care of Lubricants. Keep lubricants in tightly
filter elements in approved cleaning solvent, and dry
closed containers and, if possible, in a protected place
thoroughly.
to insure ease of handling. Remove all snow and ice
from the containers before opening them, to transfer
h. Compressed Air System. Drain accumulated
lubricants to lubricant tanks or to guns.
moisture from the compressed air reservoirs as often as
necessary.
The air reservoir is equipped with a
c. Special Equipment. This unit is equipped with a
draincock located at the end of the drain tank. When
the draincock is rotated counterclockwise, the water
cold weather operation. Proper use of this equipment
which has collected in the bottom of the tank will run
will keep the lubricants at a temperature at which they
out.
will flow freely, and prevent freezing of condensed air in
lines and pumps. Use the heat control levers to direct
i. Batteries.
The batteries installed in the
the heat into the designated heat ducts (par. 63).
lubricating unit will give satisfactory service in extreme
low temperatures if care is taken to keep the batteries
d. Lubrication. During cold weather, lubricants that
fully charged. If the lubricating unit is to remain idle for
are too heavy will make the vehicle hard to start and
any long length of time during cold weather, disconnect
difficult to operate. This will also cause rapid wear of
the batteries and store them in a warm place.
the moving parts. For lubrication at low temperature,
refer to LO 5-4930-202-20.
j. Cold Engine Starting. Before attempting to start
in subzero weather, make certain the consistency of the
e. Electrical System. The large surges of electrical
crankcase oil is such that the engine can be started.
current required to start a cold engine require good
Check the controls to make sure they are free and in
electrical contacts. Inspect, clean, and tighten all
operating condition. When the engine starts, avoid
connections, especially battery terminals.
letting it stall by leaving the choke partly open; but be
f. Fuel System. In cold weather, condensation of
careful not to flood the carburetor.
moisture in the air will cause water to accumulate in
k. Valves.
Be extremely careful in operating
tools, drums, and containers. This water will freeze and
valves as they can be easily damaged in low
form ice crystals, which clog fuel lines and carburetor
temperature.
jets unless the following precautions are taken:
(1) Use
filter paper or other approved
66. Operation in Extreme Heat
strainer when filling the fuel tank, or when
When operating in extremely high temperatures,
transferring fuel from one container to
efficient cooling and adequate lubrication of the engine
another.
and air compressor is vitally important. The cooling
(2) Remove snow or ice from the fuel tank
system must be checked frequently to make sure the air
filler cap and dispensing equipment,
circulation is not impaired. Give special attention to the
before filling the fuel tank.
engine shrouds and fins for cleanness. Inspect the
(3) Keep the filler cap tightened properly to
carburetor air cleaner frequently. Make sure the oil in
keep moisture and dirt from the tank.
the air cleaner is at proper level, and clean. Lubricate
(4) After filling or moving a fuel container,
more frequently than specified in LO 5-4930-202-12.
allow the fuel to settle before filling the
tank.
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