TM 5-3810-231-12
A - Exhaust manifold
B - Intake manifold
Figure 37. Manifolds, removal and installation.
Section X. ENGINE COOLING SYSTEM
79. General
81. Thermostat Housing and Thermostat
The cooling system consists of a radiator, water
pump, oil coolers, thermostats, fan, fan guard and
a. Removal.
Remove thermostat housing and
necessary lines and fittings to connect these components.
thermostat shown in figure 39.
The flow control thermostat regulates the flow of coolant
b. Thermostat Testing. Test the thermostat for
pumped through the engine block and oil coolers to cool
proper operation by suspending i t and a thermometer in a
the engine.
container of water.
Heat the water.
When the
thermometer indicates 170 F., the thermostat should
80. Hoses, Clamps Lines and Fittings
start to open and should be fully open when t h e
a. Removal. Remove cooling system hoses, lines
temperature reaches 1850 F. Remove the thermostat
and fittings as shown in figure 38.
from the water. The cooler surrounding air should cause
a pronounced closing action and the thermostat should be
b. Cleaning. Inspection and Repair.
completely closed within a short time.
Replace a
(1) Inspect all parts for cracks or breaks.
defective thermostat.
(2) Test the thermostat (para 81).
c. Cleaning and Inspection.
(3) Clean deposits of rust from inside of all
(1) Clean all parts with an approved cleaning
parts.
solvent and dry thoroughly.
(4) Replace all gaskets and damaged or
(2) Clean gasket material from the thermostat
defective parts as necessary.
housing and the cylinder head.
c. Installation. Install cooling system hoses, lines
and fittings as shown in figure 38.
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