TM 5-6115-593-12
TO 35C2-3-463-1
4-80. THERMOSTAT. (See figure 4-53.) The
thermostats are inside the thermostat housing mounted
at the top front of the engine.
a.
Removal. Drain coolant and remove assembly
(figure 4-53) as follows:
(1) Remove bolts (1), washers (2), connection
(3), gasket (4), bolts (5), and washers (6).
(2) Loosen clamps (9), then remove outlet (7),
tee (8), hose (10), and gasket (11).
(3) Remove thermostat (13) and gasket (14)
from housing (12).
b.
Test.
(1) Suspend thermostat in a container of clean
water.
Thermostat
must
be
must
be
completely immersed but not touching
bottom of container.
(2) Heat water gradually and stir so heat is
evenly distributed.
(3) Check temperature of water with reliable
thermometer. Do not overheat. Observe
thermostat as temperature increases. If the
thermostat is functioning properly it should
begin to open between 175 to 182°F (79 to
83° C) and be fully open at 205 F (96° C).
(4) The thermostat is not adjustable. If it does
not operate within the above limits, it should
be replaced.
(5) Install a new gasket (14) and thermostat
(13) in housing (12). Be sure hole in
thermostat is "up".
(6) Install gasket (4), connection (3), washers
(2), and bolts (1).
(7) Secure gasket (11) and outlet (7) with
washers (6) and bolts (5). Attach hose (10)
with one clamp (9). Attach tee (8) with
remaining clamp (9) and secure with
washers (6) and bolts (5).
(8) Refill cooling system; refer to tables 3-1 and
4-1.
4-81. COOLANT TEMPERATURE TRANSMITTER .
(See figure 4-40.) To remove the coolant temperature
transmitter, drain coolant into a suitable container by
removing coolant drain plug and opening draincock.
Refer to figure 4-54 and remove the nut, electrical lead,
and washers; then unscrew the temperature transmitter
from the water manifold.
a.
Inspection. Inspect transmitter for corrosion and
leakage, and ensure that the connection is
secure. The transmitter is not repairable and
replacement is necessary when it fails to
operate. If the engine is not overheating and
unit shuts down as though it were, or if the
engine continues to operate when running hot,
the transmitter should be removed and tested as
a possible cause of trouble.
b.
Test. The coolant temperature transmitter
senses the temperature of the engine coolant to
operate temperature indicator on control panel.
(1) Suspend transmitter in a container of clean
water. Transmitter should be inserted so
that
sensing
element
is
completely
immersed but connector end is out of water.
(2) Set ohmmeter to Rx10 scale and connect
ohmmeter between single conductor and
case. Heat water gradually and stir so heat
is evening distributed.
(3) Check temperature of water with reliable
thermometer. Do not overheat.
4-119
