TM 9-2350-287-20-1
1-16. EQUIPMENT OPERATION (continued).
ENGINE COOLING SYSTEM
Cooling air is drawn through the fan well cover and is forced through the radiator by two cooling fans. Airflows around
the engine and is exhausted through grilles on the vehicle deck.
Engine coolant flows from the coolant pump into a two-section oil cooler that cools the engine and transmission oil.
From the oil cooler cores, coolant flows into engine water jackets for engine block cooling. At normal operating
temperatures, the bypass thermostat is closed and the inlet thermostat is open, allowing coolant to circulate through
the radiator. Below normal operating temperatures, the inlet thermostat closes and the bypass thermostat opens,
allowing coolant to flow through the crossover tube and bypass the radiator.
The surge tank stores excess coolant, allowing coolant to flow back into the system as required to maintain the system
at full level. Air trapped in the system is bled off through the pressure relief valve, which is connected to the surge tank.
The aeration detector senses low coolant level and activates a warning indicator light on the driver’s instrument panel.
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