TM 5-3810-288-12
Section V. OPERATION UNDER UNUSUAL CONDITIONS
2-26. Operation in Extreme Cold (Below
0 F)
battery will be higher than that from a cold battery.
a. General. Operation in extreme cold presents
e. Fuel System. Keep the fuel tank as full as
special problems due to the increased brittleness of
possible at all times to minimize condensation. If the
metallic and rubber parts, the danger of freezing, and the
presence of water is noted in the fuel supply, drain the
increased difficulty of keeping parts lubricated
tank and refill it with clean fuel. Refer to figure 3-7.
adequately.
f. Starting.
Warning: Personnel should use care to keep
(1) At very low temperatures, provide heat in the
from spilling fuel, coolant, or other liquids upon
cab for as long as possible before attempting to start the
themselves. Exposed parts of the body should not
engine.
come into contact with metal during cold weather, as
Warning: Do not use an open flame as the
serious and painful injury may result.
source of heat.
b. lubrication.
(2) Crank the engine with the ignition off to free
(1) Refer to the lubrication order for special
lubricants to be used at various temperatures.
(3) Lift the choke knob to provide the richest fuel
(2) When using OES oil in the crankcase, the oil
mixture possible. Use the cold weather starting aid to
level must be checked frequently, as oil consumption
pump about three shots of fuel into the engine intake
may increase.
manifold. Advance the throttle control to its middle
c. Cooling System.
position.
(1) Drain and flush the cooling system, to insure
(4) Turn on the ignition switch and start the
proper circulation of coolant throughout the radiator core.
engine. If the engine does not start, determine whether
Clean the radiator cooling fins, particularly the air
the fuel line is frozen.
passages through the core.
g. Warm-up. Cover part of the air passages
(2) Inspect the cooling system for leaks. Replace
through the radiator, to aid warm-up and to maintain
worn or damaged hose connections. Tighten the hose
engine running temperature. During warm-up only, the
damps.
entire radiator may be covered.
(3) Fill the cooling system with the proper amount
h. Stopping. Set all dippers, buckets, or loads on
and mixture of ethylene-glycol type antifreeze.
blocks to keep them from freezing to the ground, leaving
(4) After filling the cooling system, run the engine
just enough tension in the cables to keep them taut. Set
to mix the antifreeze solution thoroughly.
all drum pawls, and release the clutches and brakes.
d. Batteries.
Turn off the engine ignition. Close all cab openings
(1) Keep the batteries fully charged at all times.
securely.
The electrolyte in a discharged battery will freeze at a
i. Operation on Snow or Ice. Take all necessary
higher temperature than that in a fully charged battery.
precautions to insure a firm footing for the truck crane.
(2) If the batteries require water, add only before
Extend the outriggers (para. 2-3) using blocking under
or during operation, or charge the batteries from an
the jack-floats to obtain firm footing.
outside source. Charging the batteries will mix the water
2-27. Operation in Extreme Heat
and the electrolyte, and prevent them from freezing.
a. General. Operation in extreme heat presents
(3) Keep the battery terminal connections clean
special problems due to the difficulty in keeping the
and free from snow or ice accumulations, which may
engine from overheating.
short circuit the batteries externally, causing them to
b. Lubrication.
discharge.
(1) Refer to the lubrication order for special
(4) In extremely low temperatures, remove the
lubricants to be used.
batteries and place them in a heated shelter when not in
(2) Make certain that the engine crankcase oil is
use.
The
current
output
from
a
warm
at the proper level. An inadequate supply of crankcase
oil will prevent proper dissipation of heat from the engine.
2-48
