SECTION III: PRINCIPLES OF OPERATION
TM 9-2350-256-20
c. ENGINE AIR INLET
The engine air inlet system provides for the use of outside air for the engine while the vehicle is in the water. The system
consists of two pipes and two rubber seals, which cover and seal each of the air intake vents on the top of the vehicle
cab.
d. ENGINE GENERATOR COOLING EXHAUST
The engine generator electrical output is switched off and the valve assembly closed by the driver from the crew
compartment to prevent water from entering the generator.
e. APU
Preparations and precautions are taken before and after submersion of the APU to prevent corrosion and separation of
hot leads due to electrolysis by exposure to salt water, and the destruction of the brushes, brush holders, and armature
by sand.
f. PERSONNEL HEATER
The personnel heater is not operable during fording operations. The air inlet and exhaust outlets are plugged during
fording operations and unplugged after fording operations.
g. ACETYLENE COMPARTMENT VENT
A vent assembly consisting of tubing, fittings, adapter plate, and gasket is attached to a boss which surrounds the four
vent holes in the left rear of the cab, to provide ventilation of the compartment during the deep water fording operation.
Two clips mounted onto the left engine air intake pipe support the vent system.
h. FUEL TANK VENT
Two 90-degree elbows, a rubber hose, two hose clamps, a seal, and a clip are the components used to vent the fuel
tanks. The rubber hose is clamped to an elbow in the left engine air intake pipe and to an elbow in the fuel tank's filler
cover. The seal is installed between the bottom of the fuel tank filler cover and the top of the fuel tank filler cap to
prevent entry of water. The clip, attached to the acetylene vent cover, keeps the hose from hanging free and being torn.
i. BILGE PUMP, MOTOR, AND SUPPORT ASSEMBLY
A centrifugal-type bilge pump with motor and support assembly is installed on the hull floor in the winch compartment.
The pump is used to remove any water which may enter the compartment during fording. The discharge of the pump is
directed through the bilge pump hose to an outlet adapter, mounted onto the right side of the personnel compartment. A
multiple purpose (wash vehicle, etc.), dacron rubber-lined hose with nozzle can be attached to the outlet adapter. A
toggle switch and indicator lamp for operating the pump are located at the right of the driver's seat on the accessories
panel. A relay, which is activated by the toggle switch, controls the pump motor. A circuit breaker mounted under the
floor plates and on the same plate as the relay provides overload protection for the pump circuit. The switch and relay
coil circuit is protected by a circuit breaker in the accessories panel.
j. CREW FAN AIR DUCT HOUSING AND BOOM BOOT DRAINS
A rubber seal between two metal plates fits into and seals the crew fan air duct housing. Shutoff hose clamps are used
to control water flow from the crew fan air duct housing and boom boot drains.
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