Section Xl. COOLING SYSTEM
b. Testing. Test thermostat for proper op-
3-38. General
The coolant is circulated by a belt-driven, self-
eration by suspending it and a thermometer
lubricated bearing type water pump. A push-
in a container of water. Heat the water. When
thermometer indicates 1500 F., thermostat
type fan forces air through the radiator. The
should be completely open. Remove thermostat
coolant passes from an outlet at bottom of
radiator through the pump directly into en-
from water. The cooler surrounding air should
gine block and is circulated through water
cause a pronounced closing action and thermo-
jacket which surrounds cylinders and valve
stat should be completely closed within a short
seats. The coolant is returned to radiator
time. Replace a defective thermostat.
through an outlet elbow on top of cylinder
c. Cleaning and Inspection.
head. A thermostat, mounted inside thermo-
(1) Clean all parts with an approved sol-
stat housing, prevents return of coolant until
vent and dry thoroughly.
a temperature of 150 F. is exceeded.
(2) Clean gasket material from the ther-
mostat housing and the cylinder head.
3-39. Radiator
(3) Inspect for cracks, breaks or other
a. Removal and Installation.
damage. Replace all damaged parts.
(1) Remove batteries (Models LEB 300
and LEW 300).
a. Removal and Installation.
(2) Drain radiator.
(1) Remove batteries (Models LEB 300
(3) Remove and install radiator as illu-
and LEW 300).
strated in figure 3-24.
(2) Drain radiator.
b. Cleaning and Inspection.
(3) Remove radiator.
(1) Clean air passages in radiator core
(4) Remove and install water pump and
with fine spray of water or compressed air.
fan assembly as illustrated in figure 3-27.
Apply water on air in opposite direction to
b. Cleaning and Inspection.
normal air flow. Reverse flush radiator as illu-
(1) Clean all parts, other than fan belt,
strated in figure 3-25.
with an approved solvent. Remove pump gas-
(2) Inspect all parts for cracks, breaks
ket material from pump.
or other damage.
(2) Inspect all parts for breaks, cracks
(3) Replace all damage or defective parts.
or other damage. Replace damaged parts.
c. Fan Belt Adjustment.
3-40. Thermostat and Housing
a. Removal and Installation. Remove and
(1) Loosen battery charging generator
install thermostat and thermostat housing as
and pull generator away from engine. Tighten
illustrated in figure 3-26.
generator bolt.
