TM-9-2320-283-20-1
TRUCK TRACTOR, LINE HAUL, 50,000 GVWR, 6X4, M915A1
TECHNICAL MANUAL; ORGANIZATIONAL MAINTENANCE PART 1 OF 3
DECEMBER 1983
TM-9-2320-283-20-1 - Page 48 of 926
TM 9-2320-283-20-1
PRINCIPLES OF OPERATION.
1-14.
COOLING SYSTEM.
a.
Cooling System Components and Piping.
RADIATOR CAP.
Closes off filler opening and keeps system
under pressure up to a maximum of 10 psi.
RADIATOR.
Coolant is circulated through a series of fins and baffles so that outside air flow can dissipate heat.
WATER FILTER.
Removes dirt and foreign particles from coolant.
WATER SHUT-OFF VALVE(S).
Can be closed to allow replacement of water filter without having to drain cooling system.
OIL
COOLER.
Engine oil
circulates through
internal tubes
of cooler, and coolant carries away heat.
THERMOSTAT.
Shuts off
coolant flow to radiator until temperature reaches 180°F.
Coolant
is
then
directed through
radiator inlet
hose
to
the radiator.
FAN
CLUTCH ACTUATOR.
When coolant
temperature rises above 190°F, actuator directs compressed air into fan
clutch, causing fan to engage.
WATER
MANIFOLD.
Collects
coolant
from cylinder
head and
directs
it to thermostat housing.
FAN.
Draws air through radiator to control coolant temperature.
FAN CLUTCH.
Air pressure from actuator engages fan when coolant temperature rises above 190°F.
AFTERCOOLER.
Coolant flowing
through core
cools hot
air
entering intake manifold port from turbocharger.
WATER CROSSOVER TUBE.
Carries coolant
under pressure from block to
after- cooler.
COMPRESSOR COOLING
WATER TUBE "A."
Carries coolant
from water pump to air compressor.
COMPRESSOR COOLING
WATER TUBE "B."
Carries coolant
from air compressor to thermostat housing.
ACCESSORY DRIVE.
Powers the fan and water pump.
THERMOSTAT DEAERATION
(AIR REMOVAL) LINE.
Escape route
for air trapped in radiator or theromstat housing.
1-28
Back to Top
