TM 5-3805-260-24
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.
2-17
