TM 5-3825-226-24
ing system. A small part of the coolant goes through
inside bypass (10) when temperature regulators (18) are
open.
CAUTION
Never run an engine unless the water
temperature regulators are Installed.
With no water temperature regulators
in the system, the coolant will
continually bypass the radiator and
the engine will get too hot.
LOCATION OF WATER TEMPERATURE
REGULATORS
The vertical radiator is made with a top tank (2) above
the core and a surge tank (9) above the top tank. Vent
tube (8) connects radiator top tank (2) and surge tank
(9).
Surge tank (9) has a shunt line (4) that connects to the
inlet of water pump (13). This shunt type system keeps
a positive pressure on the inlet of water pump (13) at all
times. When putting coolant in the cooling system,
coolant from surge tank (9) goes through shunt line (4)
to the inlet of water pump (13) and fills cylinder block
(17) from the bottom. By filling the system from the
bottom, any air in the system is pushed out through
radiator top tank (2), through vent tube (8) into surge
tank (9).
Radiator cap (1) is used to keep the correct pressure in
the cooling system. This pressure keeps a constant
supply of coolant to water pump (13).
If this pressure goes too high, a valve in radiator cap (1)
moves (opens) to get a reduction of pressure. When the
correct pressure is in the cooling system, the valve in
radiator cap (1) moves down (to the closed position).
A vent valve is installed in the vent hole located in the
front housing and the outlet elbow is used to let the air
out of the cylinder block and head when filling the
cooling system with coolant.
The vent valve is open when the cooling system is being
filled. When the engine is in operation, the vent valve
will close and not let the coolant go through. This will
help increase the temperature of the coolant at low
engine speeds.
LOCATION OF VENT HOLE
It is important to keep the vent hole clean and open. If
the vent hole is not open it will keep the engine from
completely filling with coolant.
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